2024 STEP 1 SAMPLE ITEMS

Sample Test Questions

Step 1

A Joint Program of the Federation of State Medical

Boards of the United States, Inc. (FSMB), and National

Board of Medical Examiners® (NBME®)

This booklet was updated January 2024.

For Public Release

(USMLE

) is a joint program of the FSMB and NBME.

USMLE Step 1 Test Question Formats …………………………………………………………………… 3

Introduction to USMLE Step 1 Sample Test Questions ………………………………………….. 4

USMLE Laboratory Values …………………………………………………………………………………….. 5

USMLE Step 1 Sample Test Questions……………………………………………………………………. 8

Answer Form for USMLE Step 1 Sample Test Questions………………………………………. 52

Answer Key for USMLE Step 1 Sample Test Questions…………………………………………. 53

CONTENTS

Single-Item Questions

A single patient-centered vignette is associated with one question followed by four or more response options.

The response options are lettered (A, B, C, D, E). A portion of the questions require interpretation of graphic

or pictorial materials. You are required to select the best answer to the question. Other options may be

partially correct, but there is only ONE BEST answer. This is the traditional, most frequently used multiple-

choice question format on the examination.

Strategies for Answering Single One-Best-Answer Test Questions

The following are strategies for answering one-best-answer items:

• Read each patient vignette and question carefully. It is important to understand what is being asked.

• Try to generate an answer and then look for it in the response option list.

• Alternatively, read each response option carefully, eliminating those that are clearly incorrect.

• Of the remaining options, select the one that is most correct.

• If unsure about an answer, it is better to guess since unanswered questions are automatically counted

as wrong answers.

Example Item

A 32-year-old woman with type 1 diabetes mellitus has had progressive renal failure during the past 2 years.

She has not yet started dialysis. Examination shows no abnormalities. Her hemoglobin concentration is 9 g/dL,

hematocrit is 28%, and mean corpuscular volume is 94 μm

. A blood smear shows normochromic, normocytic

cells. Which of the following is the most likely cause?

(A) Acute blood loss

(B) Chronic lymphocytic leukemia

(D) Erythropoietin deficiency

(E) Immunohemolysis

(F) Microangiopathic hemolysis

(G) Polycythemia vera

(H) Sickle cell disease

(I) Sideroblastic anemia

(J) β-Thalassemia trait

(Answer: D)

NOTE: Some item types that appear on the Step 1 examination are NOT depicted in the sample items provided

in this booklet, eg, items with multimedia features, such as audio. Also, when additional item formats are

added to the exam, notice will be provided at the USMLE website: http://www.usmle.org. You must monitor

the website to stay informed about the types of items that occur in the exam, and you must practice with the

downloadable sample test items available on the USMLE website to be fully prepared for the examination.

USMLE STEP 1 TEST QUESTION FORMATS

The following pages include 119 sample test questions. Most of these questions are the same as those you can

install on your computer from the USMLE website. Please note that reviewing the sample questions as they

appear on pages 8–51 is not a substitute for practicing with the test software. You should download and run

the Step 1 tutorial and practice test items that are provided on the USMLE website well before your test date.

The sample materials available on the USMLE website include an additional item with associated audio

findings that does not appear in this booklet. You should become familiar with this item format that will be

used in the actual examination.

Although the sample questions exemplify content on the Step 1 examination overall, they may not reflect the

content coverage on individual examinations. In the actual examination, questions will be presented in

random order; they will not be grouped according to specific content. The questions will be presented one at a

time in a format designed for easy on-screen reading, including use of the USMLE Laboratory Values table

(included here on pages 5–7) and some pictorials. Photographs, charts, and x-rays in this booklet are not of

the same quality as the pictorials used in the actual examination. In addition, you will be able to adjust the

brightness and contrast of pictorials on the computer screen.

To take the following sample test questions as they would be timed in the actual examination, you should

allow a maximum of 1 hour for each 40-item block, and a maximum of 58 minutes, 30 seconds, for the 39-item

block, for a total of 2 hours, 58 minutes, 30 seconds. Please note that the third block has 39 items instead of

40 because the multimedia item has been removed, and the recommended time to complete the block has

been adjusted accordingly. Please be aware that most examinees perceive the time pressure to be greater

during an actual examination. All examinees are strongly encouraged to practice with the downloadable

version to become familiar with all item formats and exam timing. An answer form for recording answers is

provided on page 52. An answer key is provided on page 53. In the actual examination, answers will be

selected on the screen; no answer form will be provided.

INTRODUCTION TO USMLE STEP 1 SAMPLE TEST QUESTIONS

Reference Range SI Reference Intervals

SERUM

General Chemistry:

Electrolytes

Sodium (Na

) 136–146 mEq/L 136–146 mmol/L

Potassium (K

) 3.5–5.0 mEq/L 3.5–5.0 mmol/L

Chloride (Cl

–

) 95–105 mEq/L 95–105 mmol/L

Bicarbonate (HCO

–

) 22–28 mEq/L 22–28 mmol/L

Urea nitrogen 7–18 mg/dL 2.5–6.4 mmol/L

Creatinine 0.6–1.2 mg/dL 53–106 μmol/L

Glucose Fasting: 70–100 mg/dL 3.8–5.6 mmol/L

Random, non-fasting: <140 mg/dL <7.77 mmol/L

Calcium 8.4–10.2 mg/dL 2.1–2.6 mmol/L

Magnesium (Mg

) 1.5–2.0 mg/dL 0.75–1.0 mmol/L

Phosphorus (inorganic) 3.0–4.5 mg/dL 1.0–1.5 mmol/L

Hepatic:

Alanine aminotransferase (ALT) 10–40 U/L 10–40 U/L

Aspartate aminotransferase (AST) 12–38 U/L 12–38 U/L

Alkaline phosphatase 25–100 U/L 25–100 U/L

Bilirubin, total // direct 0.1–1.0 mg/dL // 0.0–0.3 mg/dL 2–17 μmol/L // 0–5 μmol/L

Proteins, total 6.0–7.8 g/dL 60–78 g/L

Albumin 3.5–5.5 g/dL 35–55 g/L

Globulin 2.3–3.5 g/dL 23–35 g/L

Other, serum:

Amylase 25–125 U/L 25–125 U/L

Lipase 13–60 U/L 13–60 U/L

Creatinine clearance Male: 97–137 mL/min 97–137 mL/min

Female: 88–128 mL/min 88–128 mL/min

Creatine kinase Male: 25–90 U/L 25–90 U/L

Female: 10–70 U/L 10–70 U/L

Lactate dehydrogenase 45–200 U/L 45–200 U/L

Osmolality 275–295 mOsmol/kg H

O 275–295 mOsmol/kg H

Troponin I ≤0.04 ng/mL ≤0.04 µg/L

Uric acid 3.0–8.2 mg/dL 0.18–0.48 mmol/L

Lipids:

Cholesterol

Total Normal: <200 mg/dL <5.2 mmol/L

High: >240 mg/dL >6.2 mmol/L

HDL 40–60 mg/dL 1.0–1.6 mmol/L

LDL <160 mg/dL <4.2 mmol/L

Triglycerides Normal: <150 mg/dL <1.70 mmol/L

Borderline: 151–199 mg/dL 1.71–2.25 mmol/L

Iron Studies:

Ferritin Male: 20–250 ng/mL 20–250 μg/L

Female: 10–120 ng/mL 10–120 μg/L

Iron Male: 65–175 µg/dL 11.6–31.3 μmol/L

Female: 50–170 μg/dL 9.0–30.4 μmol/L

Total iron-binding capacity 250–400 µg/dL 44.8–71.6 μmol/L

Transferrin 200–360 mg/dL 2.0–3.6 g/L

USMLE Laboratory Values

Continued on Next Page

Reference Range SI Reference Intervals

Endocrine:

Follicle-stimulating hormone Male: 4–25 mIU/mL 4–25 IU/L

Female: premenopause 4–30 mIU/mL 4–30 IU/L

midcycle peak 10–90 mIU/mL 10–90 IU/L

postmenopause 40–250 mIU/mL 40–250 IU/L

Luteinizing hormone Male: 6–23 mIU/mL 6–23 IU/L

Female: follicular phase 5–30 mIU/mL 5–30 IU/L

midcycle 75–150 mIU/mL 75–150 IU/L

postmenopause 30–200 mIU/mL 30–200 IU/L

Growth hormone - arginine stimulation Fasting: <5 ng/mL <5 μg/L

Provocative stimuli: >7 ng/mL >7 μg/L

Prolactin (hPRL) Male: <17 ng/mL <17 μg/L

Female: <25 ng/mL <25 μg/L

Cortisol 0800 h: 5–23 μg/dL 138–635 nmol/L

1600 h: 3–15 μg/dL 82–413 nmol/L

2000 h: <50% of 0800 h Fraction of 0800 h: <0.50

TSH 0.4–4.0 μU/mL 0.4–4.0 mIU/L

Triiodothyronine (T

) (RIA) 100–200 ng/dL 1.5–3.1 nmol/L

Triiodothyronine (T

) resin uptake 25%–35% 0.25–0.35

Thyroxine (T

) 5–12 μg/dL 64–155 nmol/L

Free T

0.9–1.7 ng/dL 12.0–21.9 pmol/L

Thyroidal iodine (

123

I) uptake 8%–30% of administered dose/24 h 0.08–0.30/24 h

Intact PTH 10–60 pg/mL 10–60 ng/L

17-Hydroxycorticosteroids Male: 3.0–10.0 mg/24 h 8.2–27.6 μmol/24 h

Female: 2.0–8.0 mg/24 h 5.5–22.0 μmol/24 h

17-Ketosteroids, total Male: 8–20 mg/24 h 28–70 μmol/24 h

Female: 6–15 mg/24 h 21–52 μmol/24 h

Immunoglobulins:

IgA 76–390 mg/dL 0.76–3.90 g/L

IgE 0–380 IU/mL 0–380 kIU/L

IgG 650–1500 mg/dL 6.5–15.0 g/L

IgM 50–300 mg/dL 0.5–3.0 g/L

GASES, ARTERIAL BLOOD (ROOM AIR)

75–105 mm Hg 10.0–14.0 kPa

PCO

33–45 mm Hg 4.4–5.9 kPa

pH 7.35–7.45 [H

] 36–44 nmol/L

CEREBROSPINAL FLUID

Cell count 0–5/mm

0–5 × 10

Chloride 118–132 mEq/L 118–132 mmol/L

Gamma globulin 3%–12% total proteins 0.03–0.12

Glucose 40–70 mg/dL 2.2–3.9 mmol/L

Pressure 70–180 mm H

O 70–180 mm H

Proteins, total <40 mg/dL <0.40 g/L

Continued on Next Page

USMLE Laboratory Values (continued)

Reference Range SI Reference Intervals

HEMATOLOGIC

Complete Blood Count:

Hematocrit Male: 41%–53% 0.41–0.53

Female: 36%–46% 0.36–0.46

Hemoglobin, blood Male: 13.5–17.5 g/dL 135–175 g/L

Female: 12.0–16.0 g/dL 120–160 g/L

Mean corpuscular hemoglobin (MCH) 25–35 pg/cell 0.39–0.54 fmol/cell

Mean corpuscular hemoglobin conc. (MCHC) 31%–36% Hb/cell 4.8–5.6 mmol Hb/L

Mean corpuscular volume (MCV) 80–100 μm

80–100 fL

Volume

Plasma Male: 25–43 mL/kg 0.025–0.043 L/kg

Female: 28–45 mL/kg 0.028–0.045 L/kg

Red cell Male: 20–36 mL/kg 0.020–0.036 L/kg

Female: 19–31 mL/kg 0.019–0.031 L/kg

Leukocyte count (WBC) 4500–11,000/mm

4.5–11.0 × 10

Neutrophils, segmented 54%–62% 0.54–0.62

Neutrophils, bands 3%–5% 0.03–0.05

Lymphocytes 25%–33% 0.25–0.33

Monocytes 3%–7% 0.03–0.07

Eosinophils 1%–3% 0.01–0.03

Basophils 0%–0.75% 0.00–0.0075

Platelet count 150,000–400,000/mm

150–400 × 10

Coagulation:

Partial thromboplastin time (PTT/aPTT) (activated) 25–40 seconds 25–40 seconds

Prothrombin time (PT) 11–15 seconds 11–15 seconds

D-Dimer ≤250 ng/mL ≤1.4 nmol/L

Other, Hematologic:

Reticulocyte count 0.5%–1.5% 0.005–0.015

Erythrocyte count (RBC) Male: 4.3–5.9 million/mm

4.3–5.9 × 10

Female: 3.5–5.5 million/mm

3.5–5.5 × 10

Erythrocyte sedimentation rate (Westergren) Male: 0–15 mm/h 0–15 mm/h

Female: 0–20 mm/h 0–20 mm/h

CD4+ T-lymphocyte count ≥500/mm

≥0.5 × 10

Endocrine:

Hemoglobin A

≤6% ≤42 mmol/mol

URINE

Calcium 100–300 mg/24 h 2.5–7.5 mmol/24 h

Osmolality 50–1200 mOsmol/kg H

O 50–1200 mOsmol/kg H

Oxalate 8–40 μg/mL 90–445 μmol/L

Proteins, total <150 mg/24 h <0.15 g/24 h

BODY MASS INDEX (BMI) Adult: 19–25 kg/m

USMLE Laboratory Values (continued)

USMLE STEP 1 SAMPLE TEST QUESTIONS

BLOCK 1, ITEMS 1-40

1. A 14-year-old boy is brought to the emergency department by his parents because of a 1-month history of intermittent

right knee pain that has worsened during the past day. He rates his current pain as a 6 on a 10-point scale and says that

it worsens when he walks and lessens when he sits. During the past 2 weeks, he has been walking 1 mile daily in

preparation for participation in the school marching band. He has not taken any medications for his pain. He sustained

a right tibia and fibula fracture at the age of 8 years after a skateboarding accident, which was treated with internal

fixation and casting. He has asthma treated with inhaled budesonide daily and inhaled albuterol as needed. His mother

has type 2 diabetes mellitus, and his maternal grandmother has osteoporosis. The patient is 170 cm (5 ft 7 in; 77th

percentile) tall and weighs 88 kg (195 lb; >95th percentile); BMI is 31 kg/m

(98th percentile). Temperature is 37.0°C

(98.6°F), pulse is 95/min, and blood pressure is 130/80 mm Hg. Physical examination shows hyperpigmented, thickened

skin at the nape of the neck. There is tenderness to palpation of the anterior aspect of the right hip and limited range of

motion on abduction, internal rotation, and flexion of the right hip. The left hip and knees are nontender; range of motion

is full in all directions. The remainder of the examination discloses no abnormalities. Which of the following factors in

this patient’s history most increased his risk for developing this condition?

(A) BMI

(B) Family history

(D) Previous fractures

(E) Recent physical activity

2. A 14-year-old girl is brought to the office by her mother because of a 3-month history of red bumps on her skin. The

patient says the bumps are not itchy or painful but that she finds them embarrassing. She has no history of major medical

illness and takes no medications. Her vital signs are within normal limits. Physical examination shows the findings in

the photograph. Which of the following is the most likely diagnosis?

(A) Eczema

(B) Folliculitis

(D) Keratosis pilaris

(E) Urticaria

3. A 50-year-old man comes to the office because of a 2-month history of increasing daytime somnolence. He has

obstructive sleep apnea for which he has only intermittently used a continuous positive airway pressure device. He is

170 cm (5 ft 7 in) tall and weighs 181 kg (400 lb); BMI is 63 kg/m

. His temperature is 37°C (98.6°F), pulse is 100/min,

respirations are 12/min, and blood pressure is 135/80 mm Hg. Physical examination shows a gray-blue tinge to the lips,

earlobes, and nail beds. Cardiac examination shows no other abnormalities. Arterial blood gas analysis on room air

shows a pH of 7.31, PCO

of 70 mm Hg, and PO

of 50 mm Hg. Which of the following additional findings would be

most likely in this patient?

(A) Decreased serum bicarbonate concentration

(B) Increased hemoglobin concentration

(D) Left ventricular hypertrophy

4. A 32-year-old man comes to the office because of a 1-day history of cough productive of small amounts of blood and a

2-day history of shortness of breath and swelling of his ankles. He also has a 2-week history of progressive fatigue and

episodes of dark urine. He has no history of major medical illness and takes no medications. His temperature is 37°C

(98.6°F), pulse is 90/min, respirations are 18/min, and blood pressure is 175/110 mm Hg. Pulse oximetry on room air

shows an oxygen saturation of 91%. Diffuse inspiratory crackles are heard over all lung bases. There is 2+ pitting edema

of both ankles. Results of laboratory studies are shown:

Hemoglobin

8.9 g/dL

Hematocrit

27%

Serum

Urea nitrogen

55 mg/dL

Creatinine

2.9 mg/dL

Urine RBC

20–40/hpf

Urinalysis also shows some dysmorphic RBCs and rare RBC casts. Examination of a kidney biopsy specimen shows

crescentic glomerulonephritis and linear deposition of IgG along the glomerular capillaries. This patient most likely has

antibodies directed against which of the following antigens?

(A) Collagen

(B) Double-stranded DNA

(D) Phospholipid

(E) Proteins in neutrophil cytoplasm

5. A 5-year-old girl is brought to the emergency department because of a 2-day history of fever, urinary urgency, and

burning pain with urination. She has had four similar episodes during the past year. A diagnosis of urinary tract infection

is made. Subsequent renal ultrasonography shows one large U-shaped kidney. Which of the following is the most likely

embryologic origin of this patient's condition?

(A) Failure of the kidneys to rotate 90 degrees medially

(B) Failure of normal kidney ascent

(D) Fusion of the inferior poles of the metanephros during ascent

6. A 78-year-old man comes to the office for a follow-up examination. He was discharged from the hospital 1 week ago

after being treated for a nontuberculous mycobacterial infection. He started treatment with ciprofloxacin and rifampin

at that time. He also has hypertension and underwent placement of a mechanical aortic valve 6 years ago for aortic

stenosis. Other current medications are hydrochlorothiazide, lisinopril, and warfarin. His warfarin dose was doubled

4 days ago. He says that he is trying to follow a healthier diet. He drinks two 12-oz beers daily. Results of laboratory

studies done 4 days ago and today are shown

4 Days Ago

Today

Prothrombin time

11 sec (INR=1)

11.2 sec (INR=1.1)

Partial thromboplastin time

29 sec

27 sec

Which of the following is the most likely cause of this patient's laboratory findings?

(A) Decreased protein binding

(B) Eradication of gut flora

(D) Increased vegetable consumption

(E) Induction of cytochrome enzymes

7. A 32-year-old man comes to the office because of a 2-week history of fever and throat pain. He is 173 cm (5 ft 8 in) tall

and weighs 63 kg (140 lb); BMI is 21 kg/m

. His pulse is 110/min, respirations are 16/min, and blood pressure is 98/68

mm Hg. Physical examination shows scattered 2- to 4-cm lymph nodes in the neck, axillae, and inguinal regions. There

is a bilateral tonsillar exudate but no ulcerations. Results of laboratory studies are shown:

Hemoglobin

9.6 g/dL

Hematocrit

29%

Leukocyte count

1500/mm

Platelet count

60,000/mm

A heterophile antibody test result is negative. Which of the following is the most likely diagnosis?

(A) Epstein-Barr virus infection

(B) Gonococcal pharyngitis

(D) Lymphogranuloma venereum infection

(E) Streptococcal pharyngitis

8. A 50-year-old man comes to the office for a follow-up examination. He has a 2-month history of headache and shortness

of breath with exertion. He also has hypertension treated with hydrochlorothiazide for the past 2 years. His blood

pressure is 180/105 mm Hg. Ophthalmoscopic examination is most likely to show which of the following in this patient?

(A) Arteriovenous nicking

(B) Melanocytes in the uvea

(D) Posterior subcapsular cataracts

(E) Tractional retinal detachment

9. A 65-year-old woman with a history of rheumatic mitral valve disease is brought to the emergency department 30 minutes

after the sudden onset of right-sided weakness and inability to speak. Neurologic examination shows weakness of the

right lower side of the face and difficulty swallowing. Muscle strength is 3/5 on the right side. She can understand what

is said to her, but she cannot repeat words or answer questions. An ECG shows atrial fibrillation. The most likely cause

of the neurologic findings in this patient is occlusion of which of the following labeled arteries in the photograph of a

normal brain?

(A) A

(B) B

(D) D

(E) E

10. A 51-year-old man with a 10-year history of gastroesophageal reflux and suspected Barrett esophagus comes to the office

because his omeprazole dose "doesn't work around the Christmas holidays." He states that he prides himself on having

a large appetite and "holding his liquor" during the holidays. He currently takes the maximum dose of omeprazole.

Which of the following is the most appropriate initial action by the physician?

(A) Ask the patient how much he is eating and drinking during the holidays

(B) Explain the hazards of untreated reflux in the presence of Barrett esophagus

(D) Refer the patient to a gastroenterologist

(E) Switch the omeprazole to pantoprazole

11. A 60-year-old man comes to the office because of weakness, tingling of his hands and feet, irritability, and forgetfulness

for 4 months. Physical examination shows pallor, weakness, and spasticity. Deep tendon reflexes are increased.

Sensation to vibration is absent in the lower extremities. Laboratory studies show megaloblastic anemia, serum

antiparietal cell antibodies, and increased serum concentrations of methylmalonic acid and total homocyst(e)ine. The

synthesis of which of the following amino acids is most likely impaired in this patient?

(A) Cysteine

(B) Glutamine

(D) Phenylalanine

(E) Tyrosine

12. A 65-year-old woman comes to the office for a follow-up examination 1 year after she underwent operative resection of

the right colon and chemotherapy for stage III colon cancer. She reports fatigue. Physical examination shows no

abnormalities. A staging CT scan of the chest and abdomen shows five new 2- to 3-cm masses in the liver and both

lungs. This patient's cancer most likely spread to the lungs via which of the following structures?

(A) Inferior mesenteric vein

(B) Inferior vena cava

(D) Middle colic artery

(E) Pulmonary vein

(F) Superior mesenteric artery

(G) Superior vena cava

13. A 26-year-old man comes to the office because of a 1-week history of increased urinary frequency accompanied by

excessive thirst. He says he has been urinating hourly. Physical examination shows no abnormalities. Serum chemistry

studies are within the reference ranges. Urine osmolality is 50 mOsmol/kg H

O. After administration of ADH

(vasopressin), his urine osmolality is within the reference range. The most likely cause of this patient's symptoms is

dysfunction of which of the following structures?

(A) Anterior pituitary gland

(B) Bowman capsule

(D) Hypophysial portal system

(E) Loop of Henle

(F) Supraoptic nucleus

14. A 52-year-old woman comes to the office because of a 6-month history of intermittent headaches. Sometimes the pain

improves when the patient lies down in a quiet room. Her temperature is 37.5°C (99.5°F), pulse is 86/min, respirations

are 16/min, and blood pressure is 154/100 mm Hg. The lungs are clear. Cardiac examination shows the point of maximal

impulse displaced to the left and occasional skipped beats; there are no murmurs or rubs. There is no S

. Resting

electrocardiography shows left axis deviation with R waves greater than 30 mm in leads V

through V

. Which of the

following processes best explains the development of the left ventricular abnormalities in this patient?

(A) Excessive accumulation of glycogen

(B) Fibrosis of intraventricular conduction pathways

(D) Misfolding and aggregation of cytoskeletal proteins

(E) Myocyte hyperplasia as a result of induction of embryonic genes

15. A 53-year-old man comes to the physician because of a dry scaly rash on his body for the past year. He has had a 15-

kg (33-lb) weight loss during the past year. He is 178 cm (5 ft 10 in) tall and now weighs 54 kg (120 lb); BMI is

17 kg/m

. His stools have a large volume and float. Which of the following nutrient deficiencies is most likely?

(A) Magnesium

(B) Vitamin A

(cobalamin)

(D) Vitamin C

(E) Zinc

16. Serum LDL-cholesterol concentrations are measured in blood samples collected from 25 healthy volunteers. The data

follow a normal distribution. The mean and standard deviation for this group are 130 mg/dL and 25 mg/dL, respectively.

The standard error of the mean is 5.0. With a 95% confidence level, the true mean for the population from which this

sample was drawn falls within which of the following ranges (in mg/dL)?

(A) 105-155

(B) 120-140

(D) 128-132

(E) 129-131

17. A 39-year-old man comes to the physician because of a 6-month history of progressive shortness of breath. He has had

a cough productive of white sputum for 2 years. He smoked 1 pack of cigarettes daily for 16 years but quit 10 years ago.

He is in mild respiratory distress with pursed lips and a barrel chest; he is using the accessory muscles of respiration.

Breath sounds are distant and crackles are present in the lower lung fields bilaterally. Pulmonary function tests show a

decreased FEV

:FVC ratio, increased residual volume, and decreased diffusion capacity. An x-ray of the chest shows

hyperinflation and hypertranslucency of the lower lobes of both lungs. Which of the following is the most likely

diagnosis?

(A) Asthma

(B) Bronchiectasis

(D) Cystic fibrosis

(E) Emphysema

18. Investigators conduct a study that evaluates the effect of finasteride on the incidence of prostate cancer in 500 patients.

The investigators recruit an additional 1000 patients for the study. Which of the following effects will this have on the

research study?

(A) Greater chance of a Type I error

(B) Greater chance of a Type II error

(D) Less chance of a Type II error

(E) Impossible to predict

19. An 82-year-old woman has a 7-month history of increasing indigestion, upper abdominal bloating, and early satiety.

Photomicrographs of her gastric wall are shown: A is a hematoxylin and eosin stain; B is a mucin stain; C is an

immunostain for cytokeratin. Which of the following is most likely to have decreased expression in these cells?

(A) Cathepsin D

(B) Epithelial cadherins

(D) Integrins

(E) Type IV collagenase

(F) Vascular endothelial growth factor

20. A 54-year-old woman comes to the physician because she would like to lose weight. She has been on numerous diets in

the past with limited success. Both her parents have type 2 diabetes mellitus. She is 160 cm (5 ft 3 in) tall and weighs

69 kg (152 lb); BMI is 27 kg/m

. Her blood pressure is 140/90 mm Hg. Fasting serum glucose concentration is

102 mg/dL. Compared with a woman of the same age whose weight is normal, which of the following serum

abnormalities is most likely in this patient?

(A) Decreased cholesterol excretion

(B) Decreased estrone concentration

(D) Increased fasting insulin concentration

(E) Increased growth hormone concentration

(F) Increased thyroid-stimulating hormone concentration

21. A 65-year-old woman is brought to the emergency department because of a 10-minute history of chest tightness and

severe pain of her left arm. Physical examination shows jugular venous distention. Crackles are heard over the lung

fields. An ECG shows ST-segment elevation greater than 1 mm in leads V

through V

and new Q waves. Serum studies

show an increased troponin I concentration. Which of the following labeled points in the graph best represents the

changes in cardiac function that occurred during the first 10 seconds after the onset of pain in this patient?

(A) W → X

(B) W → Y

(D) X → W

(E) X → Y

(F) X → Z

(G) Z → W

(H) Z → X

(I) Z → Y

22. A previously healthy 33-year-old woman is brought to the emergency department by the Secret Service for stalking the

president of the USA for 2 months. She claims to be married to the president's twin brother and states that the president

just had his twin kidnapped to avoid competition. She speaks rapidly and is difficult to interrupt. Her associations are

often loose. She says, "I haven't slept for days, but I won't even try to sleep until my husband is rescued. God has been

instructing me to take over the White House. I can't wait to be reunited with my husband. I hear his voice telling me

what to do." When asked about drug use, she says she uses only natural substances. She refuses to permit blood or urine

tests, saying, "I don't have time to wait for the results." Which of the following is the most likely diagnosis?

(A) Bipolar disorder, manic, with psychotic features

(B) Brief psychotic disorder

(D) Psychotic disorder due to general medical condition

(E) Schizophrenia

23. In informing a couple that their newborn has Down syndrome, there is a specific, relatively limited amount of information

that the consulting physician should give immediately. The rest can be discussed at a later time. Which of the following

best explains the purpose of using this approach to disclosure?

(A) Allowing the couple's primary care physician to discuss most of the information with them

(B) Allowing the parents time to tell other family members

(D) Disclosing the most important information so that it can be understood as fully as possible

(E) Influencing the parents' course of action about what is medically most appropriate

24. A 62-year-old man comes to the physician because of a 6-month history of urinary hesitancy and dribbling after urination.

He has to urinate two to three times nightly. Physical examination shows a diffusely enlarged, firm, and nontender

prostate. Which of the following is most likely to have contributed to the development of this patient's condition?

(A) Activation of the α

-adrenergic receptor

(B) Conversion of testosterone to dihydrotestosterone

(D) Inhibition of the α

-adrenergic receptor

(E) Production of prostate-specific antigen

25. A 19-year-old man who is in the US Army is brought to the emergency department 45 minutes after he sustained a knife

wound to the right side of his chest during an altercation. He has no history of major medical illness and takes no

medications. His temperature is 36.9°C (98.4°F), pulse is 110/min, respirations are 24/min, and blood pressure is

114/76 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 94%. On physical examination, the trachea

appears to be shifted to the left. Pulmonary examination of the right chest is most likely to show which of the following

findings?

Fremitus

Percussion

Breath Sounds

(A)

Decreased

dull

decreased

(B)

Decreased

hyperresonant

decreased

(C)

Decreased

hyperresonant

dull

(D)

Increased

dull

bronchial

(E)

Increased

dull

decreased

26. A 34-year-old man comes to the office because of a 1-month history of diarrhea. He has a history of pheochromocytoma

treated 2 years ago. His mother is being treated for a tumor of her parathyroid gland. He has no other history of major

medical illness and takes no medications. His temperature is 37.0°C (98.6°F), pulse is 84/min, respirations are 10/min,

and blood pressure is 120/75 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. Vital signs are

within normal limits. Physical examination shows a 3-cm, palpable mass on the right side of the neck. A biopsy specimen

of the mass shows a neuroendocrine neoplasm of parafollicular cell origin. The most likely cause of the findings in this

patient is a mutation in which of the following types of genes?

(A) Cell cycle regulation gene

(B) DNA mismatch repair gene

(D) Proto-oncogene

(E) Tumor suppressor gene

27. A 56-year-old man is brought to the emergency department by his wife 30 minutes after he had severe upper back pain

and hoarseness before becoming comatose. He has hypertension treated with hydrochlorothiazide. His temperature is

37°C (98.6°F), pulse is 100/min, and blood pressure is 160/80 mm Hg in the right arm and 100/60 mm Hg in the left

arm. Ophthalmologic examination shows ptosis and miosis of the left eye. There is anhidrosis of the left side of the

forehead, right hemiplegia, and a decreased left radial pulse. A chest x-ray shows a widened mediastinum. Which of the

following conditions is the most likely cause of these findings?

(A) Dissection of the aorta distal to the left subclavian artery

(B) Dissection of the aorta extending into the left carotid artery

(D) Dissection of the proximal aorta extending into the right subclavian artery

(E) Superior sulcus tumor

(F) Thrombus of the left carotid artery

28. A 68-year-old man with alcohol use disorder comes to the office because of a 3-month history of intermittent blood in

his urine; he has had no pain. He is a retired laboratory technician from a company that produces naphthylamine. He has

smoked 1½ packs of cigarettes daily for 45 years. A CT scan of the abdomen shows a mass in the pelvis of the left

kidney. A photograph of the surgically resected kidney is shown. The neoplastic process in this kidney is most likely to

be which of the following?

(A) Angiomyolipoma

(B) Metastatic melanoma

(D) Oncocytoma

(E) Urothelial carcinoma

29. A 27-year-old woman comes to the emergency department because of a 1-hour history of severe shortness of breath. She

has just returned from a cross-country flight. She has a history of borderline hypertension. Her temperature is 36.9°C

(98.5°F), pulse is 113/min, respirations are 28/min, and blood pressure is 138/85 mm Hg. Physical examination shows

that the right calf has an increased circumference compared with the left calf, and there is tenderness behind the right

knee. Which of the following is the most likely underlying cause of this patient's condition?

(A) Antithrombin III deficiency

(B) Factor V Leiden mutation

(D) Protein C deficiency

(E) von Willebrand disease

30. A 20-year-old woman is brought to the urgent care center because of a 2-month history of progressive weakness of her

arms. She also has a 1-week history of moderate back pain and headache. Her only medication is ibuprofen as needed

for pain. Muscle strength is 3/5 in the upper extremities. Sensation to pinprick is decreased over the upper extremities.

MRI of the spine shows a central syrinx in the cervical spinal cord. It is most appropriate to obtain specific additional

history regarding which of the following in this patient?

(A) Diet

(B) Family illness

(D) Trauma

(E) Unintended weight loss

31. A 3-year-old boy is brought to the office because of a 2-day history of bulging of his left eye. He says his eye hurts. He

has no history of major medical illness or recent trauma to the area, and he receives no medications. Vital signs are

within normal limits. Physical examination shows exophthalmos of the left eye. MRI of the brain shows a 2-cm mass

involving the ocular muscles of the left eye. A biopsy specimen of the mass shows malignant cells, some of which have

striations. Which of the following is the most likely diagnosis?

(A) Neuroblastoma

(B) Pheochromocytoma

(D) Rhabdomyosarcoma

(E) Thyroid cancer

32. An 18-year-old woman with sickle cell disease is brought to the emergency department by her parents because of a 2-

hour history of severe abdominal pain and nausea. Her parents say that she had a cheeseburger, milk shake, and chocolate

bar for lunch. Her temperature is 37°C (98.6°F). Physical examination shows tenderness over the right upper quadrant

of the abdomen, radiating to the right shoulder. Ultrasonography of the right upper quadrant of the abdomen shows

gallstones. Which of the following is the most likely underlying cause of this patient's current condition?

(A) Decreased hepatic secretion of lecithin

(B) Decreased reabsorption of bile salts

(D) Infestation with parasites secreting β-glucuronidase

(E) Overload of unconjugated bilirubin

33. In a sample of 100 individuals, the mean leukocyte count is 7500/mm

, with a standard deviation of 1000/mm

. If the

leukocyte counts in this population follow a normal (gaussian) distribution, approximately 50% of individuals will have

which of the following total leukocyte counts?

(A) 5500–9500/mm

(B) <6500/mm

or >8500/mm

(D) <7500/mm

(E) >9500/mm

34. A previously healthy 52-year-old woman comes to the physician because of a 2-month history of fatigue, constipation,

and frequent urination. Her temperature is 37.1°C (98.8°F), pulse is 80/min, respirations are 14/min, and blood pressure

is 140/90 mm Hg. Diffuse crackles are heard bilaterally. Her serum calcium concentration is 11.1 mg/dL, and serum

parathyroid hormone concentration is decreased. A chest x-ray shows bilateral hilar lymphadenopathy and interstitial

infiltrates. Which of the following is the most likely cause of this patient's hypercalcemia?

(A) Calcitriol production by activated macrophages

(B) Local resorption of bone by metastases

(D) Secretion of parathyroid hormone

(E) Secretion of thyroid-stimulating hormone

35. A 55-year-old woman comes to the clinic because of a 2-month history of increasingly severe vaginal pain and itching

during sexual intercourse. She avoids intercourse with her husband because of the symptoms. She has been in a

monogamous relationship with her husband for the past 25 years. She has type 2 diabetes mellitus. Her vital signs are

within normal limits. Pelvic examination shows edematous and erythematous vaginal mucosa with white discharge. A

photomicrograph of a vaginal smear is shown. Which of the following is the most likely causal infectious agent?

(A) Candida albicans

(B) Chlamydia trachomatis

(D) Human papillomavirus

(E) Trichomonas vaginalis

36. A 24-year-old woman is brought to the physician 1 month after she was involved in a motor vehicle collision that left

her weak and unable to walk. Physical examination shows weakness of both hands and atrophy of the intrinsic hand

muscles bilaterally. There is weakness and increased muscle tone of the lower extremities on passive range of motion.

Deep tendon reflexes are normal at the biceps and triceps bilaterally and are increased at the knees and ankles. Babinski

sign is present bilaterally. Sensation to pinprick is absent at and below the level of the clavicles. The lesion in this patient

is most likely located at which of the following spinal cord levels?

(A) C5

(B) C7

(D) T3

(E) T5

37. A 45-year-old man is brought to the emergency department 30 minutes after the sudden onset of crushing chest pain. His

father, maternal aunt, and paternal uncle all died of myocardial infarctions under the age of 50 years. Physical

examination shows tendinous xanthomas on the hands and thickened Achilles tendons. Serum lipid studies show a total

cholesterol concentration of 410 mg/dL, HDL-cholesterol concentration of 30 mg/dL, and triglyceride concentration of

140 mg/dL. The diagnosis of myocardial infarction is made. This patient most likely has a deficiency of which of the

following?

(A) Apo B48

(B) Apo C

(D) LDL receptor

(E) Lipoprotein lipase activity

38. A previously healthy 19-year-old man is brought to the emergency department 30 minutes after he collapsed while

playing softball. He had severe, sharp, upper back pain prior to the game. He is 196 cm (6 ft 5 in) tall. His temperature

is 37°C (98.6°F), pulse is 130/min, respirations are 24/min, and blood pressure is 80/50 mm Hg. Physical examination

shows pallor and no jugular venous distention. Breath sounds are clear. The carotid pulses are weak. A grade 4/6, late

diastolic murmur is heard at the lower left sternal border. Which of the following is the most likely cause of this patient's

cardiac findings?

(A) Atrial septal defect

(B) Mitral stenosis

(D) Perforated tricuspid valve

(E) Stretched aortic anulus

39. A 27-year-old woman is brought to the emergency department because of a 2-week history of double vision. Neurologic

examination shows that the left eye does not adduct past the midline on horizontal gaze when the patient looks to the

right. Leftward horizontal gaze is normal. This patient's ocular movement deficit is most likely caused by damage to

which of the following structures?

(A) Left abducens nerve

(B) Left medial longitudinal fasciculus

(D) Right abducens nerve

(E) Right medial longitudinal fasciculus

(F) Right nucleus of the abducens nerve

40. A 45-year-old woman is recovering from acute respiratory distress syndrome secondary to gallstone pancreatitis. A

drawing of the alveolar wall is shown. Which of the following labeled cells will most likely proliferate and reestablish

the injured epithelial layer in this patient?

USMLE STEP 1 SAMPLE TEST QUESTIONS

BLOCK 2, ITEMS 41-80

41. An 11-year-old girl is brought to the emergency department by her parents because of a 1-week history of breast

enlargement. She has not had pain or nipple discharge. She has asthma treated with inhaled albuterol as needed. She

does not smoke cigarettes, drink alcoholic beverages, or use illicit drugs. She is at the 50th percentile for height and

weight. Vital signs are within normal limits. Examination of the breasts shows minimal enlargement under the areolae

and mild enlargement of the diameter of the areolae without nipple discharge; no masses are palpated. There is scant

pubic hair. Which of the following best describes the sexual maturity rating for this patient?

(A) 1

(B) 2

(D) 4

(E) 5

42. A 5-year-old boy is brought to the emergency department by his mother because of an episode of bloody stool 3 hours

ago. The mother says the stool was hard "like pebbles" and she noted bright red blood on the tissue when the patient

cleaned himself. His previous bowel movement was 5 days ago. The patient has no abdominal or rectal pain now, but

he did have abdominal pain during his bowel movement 5 days ago. He has no history of major medical illness and

receives no medications. Vaccinations are up-to-date. The patient has no recent history of travel. He is at the

5th percentile for height and the 10th percentile for weight; BMI is at the 50th percentile. Vital signs are within normal

limits. Abdominal examination shows hypoactive bowel sounds and a soft, slightly distended abdomen that is not tender

to palpation. Rectal examination shows 1 cm of bright red rectal mucosa protruding from the right side of the anus; there

is no rectal bleeding. The remainder of the examination shows no abnormalities. Which of the following is the most

likely cause of this patient's physical findings?

(A) Constipation

(B) Cystic fibrosis

(D) Hookworm infestation

(E) Intussusception

43. A 25-year-old woman comes to the office because of a 3-day history of fever, chills, severe headache, weakness, muscle

pain, loss of appetite, vomiting, diarrhea, and moderate abdominal pain. She is in nursing school and returned from a

medical missions trip in West Africa 10 days ago. Her symptoms began abruptly while she was shopping in a

supermarket after her return. Temperature is 39.0°C (102.2°F), pulse is 100/min, respirations are 22/min, and blood

pressure is 110/70 mm Hg. The patient appears ill and in mild respiratory distress. Physical examination discloses poor

skin turgor and hyperactive bowel sounds. Muscle strength is 4/5 throughout. Laboratory studies show leukopenia and

thrombocytopenia. Which of the following is the most sensitive and specific test for detection of the suspected viral

genome in this patient?

(A) Microarray analysis

(B) Northern blot

(D) Southern blot

(E) Western blot

44. A 56-year-old man comes to the office because of a 1-month history of pain and tingling of his hands and a 6-month

history of paresthesia of his feet. As part of the workup, a nerve biopsy specimen is obtained and analyzed at the electron

microscopic level. The biopsy specimen shows marked loss of structures labeled by the X's in the photomicrograph of

a normal biopsy specimen shown. The loss of these structures is most likely to cause which of the following neurologic

findings in this patient?

(A) Decreased sensitivity of the deep tendon reflex

(B) Impaired stereognosis

(D) Muscle atrophy

(E) Vasoconstriction

45. A 5-month-old boy is brought to the clinic by his mother because of a 10-day history of “coughing spells” that occur

several times daily and last 1 to 2 minutes; he often vomits afterwards. He was delivered at term to a 16-year-old patient,

gravida 1, para 1, following an uncomplicated pregnancy and spontaneous vaginal delivery in Mexico. His parents

immigrated to the USA shortly after his birth. He has no history of major medical illness and receives no medications.

He has never been to a physician for a well-child examination and has not received any vaccinations. He appears well.

Vital signs, including oxygen saturation, are within normal limits. During the physical examination, he coughs

uncontrollably for 2 minutes, after which there is a gasping sound and subsequent vomiting. Afterwards, he appears

exhausted. Physical examination shows no nasal flaring or intercostal or subcostal retractions. The lungs are clear; no

wheezes or crackles are heard. A drug from which of the following classes is most appropriate for this patient?

(A) Cephalosporin

(B) Fluoroquinolone

(D) Penicillin

(E) Sulfonamide

46. A 40-year-old woman comes to the physician because of a runny nose, sneezing, and itching eyes on exposure to cats

since childhood. Antiallergy drugs have not provided relief. Her symptoms improve with a program of desensitization

involving administration of increasing doses of the allergen. Which of the following is the most likely mechanism of the

beneficial effect of this treatment?

(A) Formation of dimers that stimulate clearance by macrophage phagocytosis

(B) Increased production of IgG antibodies that block allergen binding to mast cells

(D) Production of an anti-idiotypic antibody to IgE that results in its clearance

(E) Stimulation of macrophages to produce anti-inflammatory cytokines

47. A 3-week-old girl delivered at term with no complications is brought to the physician by her mother because of a 1-week

history of yellow eyes and skin, tan-colored stools, and dark brown urine. The newborn has been breast-feeding without

difficulty. She is alert and appears to be in no distress. She is at the 50th percentile for length and weight. Physical

examination shows scleral icterus and jaundice. There is mild hepatomegaly; the spleen is not palpable. Laboratory

studies show:

Hemoglobin

14.4 g/dL

Hematocrit

43%

Leukocyte count

8000/mm

Serum

Albumin

3.5 g/dL

Bilirubin, total

14 mg/dL

Direct

12.5 mg/dL

AST

50 U/L

ALT

45 U/L

Which of the following is the most likely diagnosis?

(A) Biliary atresia

(B) Crigler-Najjar syndrome, type I

(D) Hemolytic disease of the newborn

(E) Physiologic jaundice

48. A 65-year-old woman comes to the physician for a follow-up examination after blood pressure measurements were

175/105 mm Hg and 185/110 mm Hg 1 and 3 weeks ago, respectively. She has well-controlled type 2 diabetes mellitus.

Her blood pressure now is 175/110 mm Hg. Physical examination shows no other abnormalities. Antihypertensive

therapy is started, but her blood pressure remains elevated at her next visit 3 weeks later. Laboratory studies show

increased plasma renin activity; the erythrocyte sedimentation rate and serum electrolytes are within the reference

ranges. Angiography shows a high-grade stenosis of the proximal right renal artery; the left renal artery appears normal.

Which of the following is the most likely diagnosis?

(A) Atherosclerosis

(B) Congenital renal artery hypoplasia

(D) Takayasu arteritis

(E) Temporal arteritis

49. A 46-year-old woman comes to the physician because of a 1-month history of fatigue, weakness, and palpitations. She

has advanced kidney disease as a result of continued use of combination analgesics for low back pain. She has

hypertension well controlled with a loop diuretic, a β-adrenergic blocker, and a dihydropyridine calcium channel

blocker. She has a history of gastritis and hemorrhoids associated with occult blood in the stools. She is in no acute

distress. Her temperature is 36.8°C (98.2°F), pulse is 74/min, respirations are 14/min, and blood pressure is

150/86 mm Hg. Physical examination shows mild midepigastric tenderness to palpation and 2+ edema of the lower

extremities. Cardiac examination shows an S

gallop. Test of the stool for occult blood is positive. Laboratory studies

show:

Hemoglobin

8.8 g/dL

Hematocrit

26.8%

Mean corpuscular volume

82 μm

Serum

Ferritin

262 ng/mL

Folate

284 ng/mL (N=150–450)

Total iron

60 μg/dL

Transferrin saturation

22% (N=20%–50%)

Lactate dehydrogenase

62 U/L

Which of the following is the most likely cause of this patient's anemia?

(A) Bone marrow suppression

(B) Decreased erythropoietin production

(D) Iron deficiency anemia

(E) Splenic sequestration

50. A 46-year-old woman comes to the physician because of a 3-day history of intermittent pain with urination and increased

urinary frequency. She says that she had one similar episode during the past 6 months. She also has had irregular menses,

and her last menstrual period occurred 2 months ago. She has not had fever, nausea, vomiting, or blood in her urine. She

is sexually active with one male partner. Physical examination shows no abnormalities. Urinalysis shows:

RBC

3–5/hpf

WBC

10–20/hpf

Nitrites

positive

Leukocyte esterase

positive

Bacteria

positive

Which of the following is the strongest predisposing risk factor for the development of this patient's condition?

(A) Leiomyomata uteri

(B) Perimenopause

(D) Sexual intercourse

51. A 37-year-old man comes to the office because of a 3-week history of itchy patches of skin and a burning sensation in

his feet. He works as a dishwasher and says he frequently works in wet shoes and socks. Vital signs are within normal

limits. Physical examination shows the findings in the photograph; these findings are also present on the soles of both

feet. The most appropriate pharmacotherapy for this patient will inhibit the activity of which of the following enzymes?

(A) Chitin synthase

(B) 1,3-β-D-Glucan synthase complex

(D) Squalene monooxygenase

(E) Thymidylate synthase

52. A 10-year-old boy is brought to the emergency department in the middle of summer because of fever, headache, and

photophobia. Several of his camp mates have had a similar illness. Physical examination shows mild nuchal rigidity. A

lumbar puncture is performed. Laboratory studies show:

Serum glucose

90 mg/dL

Cerebrospinal fluid

Pressure, opening

50 mm H

Glucose

65 mg/dL

Total protein

70 mg/dL

Leukocyte count

43/mm

(95% lymphocytes)

Which of the following infectious agents is the most likely cause of these findings?

(A) Adenovirus

(B) Enterovirus

(D) Neisseria meningitidis

(E) Streptococcus pneumoniae

53. A 55-year-old woman comes to the physician because of a 3-week history of right shoulder pain that occurs when she is

lying on her right shoulder in bed. There is tenderness to palpation over the greater tubercle. An x-ray of the right

shoulder is shown; the arrows indicate a calcium deposit. Further examination of this patient will most likely show

impairment of which of the following active shoulder movements?

(A) Abduction

(B) Adduction

(D) Flexion

(E) Internal rotation

54. A 31-year-old woman with a 5-year history of fatigue comes to the physician for an initial visit. She has seen four other

physicians for the same condition within the past 6 months, but no abnormalities were found. She gives the physician a

large folder that contains her medical records. She says, "I can barely get out of bed most mornings, but nobody can

figure out why because all of my tests turn out normal. I really think I have chronic fatigue syndrome. What do you

know about this condition?" The physician has not treated any patient with chronic fatigue syndrome before. Which of

the following initial statements by the physician is most appropriate to establish rapport with this patient?

(A) "From the size of the folder you brought, it looks like you've had very thorough examinations in the past."

(B) "I don't have much experience with chronic fatigue syndrome, but I'm committed to learning as much as I can

about it."

(D) "Let's start over from scratch. We'll need to repeat complete testing."

(E) "When nothing abnormal is found during thorough examinations and laboratory studies, there is often an

underlying psychological cause of the symptoms."

55. A 28-year-old man comes to the physician because of a 2-month history of a rash on his wrists and hands. He is a first-

year mortuary science student. He also works on his grandfather's farm each weekend. His hobbies include raising

homing pigeons and repairing vintage motorcycles. He recently changed to a different type of laundry detergent to save

money. Physical examination shows a diffuse erythematous rash involving both hands up to the wrist creases. The rash

does not extend over any other parts of the body. Which of the following is the most likely cause of this patient's rash?

(A) Change in laundry detergent

(B) Exposure to chemicals during motorcycle repair

(D) Pesticide exposure

(E) Use of latex gloves

56. A 22-year-old woman at 32 weeks’ gestation comes to the office for a prenatal visit. Vital signs are within normal limits.

Fundal height and fetal heart tones are also normal. At the end of the examination, the patient tells the physician that her

friend is a certified lay midwife and has recently convinced her to have a home birth. The patient asks the physician if

he would be the backup for the midwife in case of an emergency. Which of the following is the most appropriate initial

response by the physician?

(A) “I’m sorry, but I would no longer be able to be your doctor if you pursue a home birth.”

(B) “I would like to meet with your friend before I decide.”

(D) “Let’s set up an appointment next week to discuss your birth plan in detail.”

(E) “Perhaps your midwife could act as your birth coach instead.”

57. A 36-year-old woman with hypertension comes to the office because she thinks she may be “going through early

menopause.” She has not had a menstrual period since her most recent office visit 6 months ago. During this time, she

also has been “gaining weight around the middle” despite increased exercise; she has had a 6.3-kg (14-lb) weight gain.

She has no other history of major medical illness. Her only medication is lisinopril. She does not smoke, drink alcohol,

or use illicit drugs. She is 168 cm (5 ft 6 in) tall and weighs 107 kg (236 lb); BMI is 38 kg/m

. Vital signs are within

normal limits. Examination shows a uterus consistent in size with a 24-week gestation. Pelvic ultrasonography shows

oligohydramnios and a fetus with a misshapen cranium, pericardial effusion, small bladder, and echogenic bowel. The

most likely cause of the fetal abnormalities in this patient’s pregnancy is interference with which of the following?

(A) Fetal lung/epithelial differentiation

(B) Fetal lung/surfactant development

(D) Maternal placental perfusion

(E) Maternal prostaglandin synthesis

58. A 67-year-old man comes to the office because he is concerned about memory loss. He says he sometimes forgets the

names of acquaintances he sees while he is out shopping. He also has occasional word-finding difficulty and forgets to

buy some items when he goes shopping unless he makes a list. He lives alone and is able to manage his finances, cook,

and shop without help. He works part-time as an accountant. He has gastroesophageal reflux disease and hypertension.

Current medications are hydrochlorothiazide and omeprazole. Vital signs are within normal limits. Physical and

neurologic examinations show no abnormalities. On mental status examination, he is fully oriented. His speech is

normal, and thoughts are organized. His mood is euthymic, and he has a full range of affect. His concentration is intact,

and he is able to perform calculations quickly and accurately. He can name objects accurately and follow written and

verbal commands. He recalls three of four objects after 5 minutes. Which of the following is the most appropriate

physician response to this patient’s concern?

(A) “I am concerned about your memory loss. Let’s discuss how to further evaluate your memory.”

(B) “There's no need to worry right now, but let's meet again in 6 months.”

ways to plan for the future.”

(D) “Your episodes of forgetfulness are likely just ‘Senior Moments,’ but we should obtain in-depth laboratory test

results and an MRI to be certain.”

(E) “Your examination findings indicate that your memory loss is likely consistent with the normal aging process.”

59. A 42-year-old woman comes to the office because of a 1-year history of a left breast mass. She had been living in another

country for the past 2 years; a physician in that country told her that the lesion was a cyst. Since returning to the USA

12 weeks ago, she has noticed that the mass has increased in size and is now so tender that any physical contact is

painful. She has not had any other breast masses, skin changes, or nipple changes. She has a history of cysts in both

breasts, and has undergone aspirations of 2 prior cysts; pathologic examination both times showed no abnormalities. She

has a 1-year history of yellow nipple discharge from both breasts and premenstrual bilateral breast pain. She has no other

history of serious illness and takes no medications. There is no family history of breast cancer. Vital signs are within

normal limits. Physical examination shows a 3-cm, firm, extremely tender and partially mobile mass in the upper outer

quadrant of the left breast. Mammography shows a 3.1-cm, irregular mass in the left breast corresponding to the palpable

area of the mass. Photomicrographs of an excisional biopsy specimen are shown. Which of the following pathologic

findings most strongly suggests malignancy in this patient?

(A) Compressed ducts

(B) Dense fibrosis

(D) Multiple large and small cysts

(E) Pleomorphic irregular glands

60. A 30-year-old woman comes to the office because of a 4-day history of an increasingly severe, painful rash over her

body and in her mouth. The rash began over her trunk area but spread within a day to her face and extremities. Two days

before development of the rash, she had flu-like symptoms with muscle aches and fatigue as well as a nonproductive

cough, sore throat, and runny nose. Ten days ago, she began treatment with trimethoprim-sulfamethoxazole for a urinary

tract infection; she takes no other medications. Temperature is 39.0°C (102.2°F), pulse is 120/min, respirations are

25/min, and blood pressure is 165/105 mm Hg. Physical examination shows diffuse brownish red macular exanthema

with bullous lesions. Epidermis at an uninvolved site can be removed with mild tangential pressure. Examination of a

biopsy specimen of one of the lesions shows necrosis of keratinocytes throughout the epidermis. There is minimal

lymphocytic infiltration within the superficial dermis. Which of the following is the most likely diagnosis?

(A) Erythema multiforme

(B) Linear IgA bullous dermatosis

(D) Staphylococcal scalded skin syndrome

(E) Toxic epidermal necrolysis

61. A 78-year-old woman is admitted to the hospital because of a 1-week history of jaundice. CT scan of the abdomen shows

a mass suggestive of pancreatic cancer. Three hours later, the on-call physician enters the patient's room to discuss the

prognosis and obtain consent for a biopsy scheduled for the next morning. On entering the room, the physician greets

the patient and her husband. The physician then learns that the patient speaks only Mandarin. Her husband is fluent in

Mandarin and English. The hospital interpreter is not available until tomorrow morning. The patient's husband appears

anxious and insists that the physician speaks to him and allows him to serve as an interpreter for his wife. Which of the

following is the most appropriate next step in management?

(A) Allow the patient's husband to serve as an interpreter

(B) Consult the hospital ethics committee

(D) Use a telephone interpreter service

62. Results of a study that examined the impact of risk factors on cardiovascular health are being evaluated. In the study,

serum LDL-cholesterol (LDL) concentration is found to have a correlation of 0.6 with serum high-sensitivity C-reactive

protein (hs-CRP) concentration. Which of the following statements best describes the relationship between LDL

concentration and hs-CRP concentration based on this finding?

(A) Higher LDL concentrations are associated with higher hs-CRP concentrations

(B) Higher LDL concentrations are associated with lower hs-CRP concentrations

(D) Higher LDL concentrations cause lower hs-CRP concentrations

63. A 45-year-old man comes to the physician because of a 10-year history of heartburn that occurs after he eats late at night

or consumes spicy food. He has had no weight loss or difficulty swallowing. He takes over-the-counter antacids as

needed, but they relieve his discomfort only temporarily. Physical examination shows no abnormalities. An endoscopy

is done. The distal esophagus is shown in the photograph. Which of the following is the most likely cause of this patient's

symptoms?

(A) Defect in secretin production

(B) Excessive gastrin production

(D) Failure of primary esophageal peristalsis

(E) Failure of saliva production

64. A 72-year-old man comes to the physician for a health maintenance examination. He has no personal or family history

of major medical illnesses. He has never smoked cigarettes. Pulse oximetry on room air shows an oxygen saturation of

98%. Physical examination shows plethoric skin and splenomegaly. Laboratory studies show:

Hemoglobin

21.1 g/dL

Hematocrit

61%

Leukocyte count

15,000/mm

Segmented neutrophils

68%

Basophils

Lymphocytes

28%

Platelet count

501,000/mm

Leukocyte alkaline phosphatase

increased

A peripheral blood smear shows occasional giant platelets. The primary hematologic defect in this patient most likely

occurred in which of the following cells?

(A) Erythroid progenitor

(B) Hematopoietic stem

(D) Megakaryocyte progenitor

(E) Pluripotent stem

65. A 35-year-old man is brought to the emergency department 30 minutes after he sustained a cut on his hand while loading

cargo at his job. He lives alone and takes most of his meals at a local restaurant. He eats mostly snack foods at the bar

and fast food. He drinks four to six 12-oz beers daily and double that amount on weekends. He takes no medications.

Physical examination shows a 3-cm laceration on the right hand that is bleeding steadily. Laboratory studies show a

hemoglobin concentration of 11 g/dL, leukocyte count of 4000/mm

, and platelet count of 150,000/mm

. A

photomicrograph of a peripheral blood smear is shown. A deficiency of which of the following is the most likely cause

of this patient's anemia?

(A) Folic acid

(B) Glucose-6-phosphate dehydrogenase

(D) Vitamin B

(thiamine)

(E) Vitamin B

(pyridoxine)

66. A 3800-g (8-lb 6-oz) newborn is delivered vaginally at 39 weeks' gestation after an uncomplicated pregnancy. Apgar

scores are 9 and 9 at 1 and 5 minutes, respectively. The newborn is crying, has pink skin, and appears vigorous. Physical

examination shows a vagina and also a structure that appears to be a penis, with the urethra located at the base near the

opening of the vagina. Chromosomal analysis is ordered. Which of the following is the most likely cause of the intersex

findings in this newborn if the karyotype is found to be 46,XX?

(A) 17α-Hydroxyprogesterone deficiency

(B) Increased concentration of müllerian-inhibiting substance

(D) Presence of the sex-determining region Y gene

(E) 5α-Reductase deficiency

67. An 80-year-old woman is brought to the emergency department (ED) 30 minutes after she fell out of her wheelchair at

home. This is the second visit to the ED for a fall during the past 3 months. She lives with her daughter and son-in-law,

who say they “do the best we can.” The patient has dementia, Alzheimer type, coronary artery disease, type 2 diabetes

mellitus, and hypertension. Current medications are amlodipine, aspirin, atorvastatin, donepezil, long-acting insulin, and

lisinopril. Five years ago, she underwent bilateral below-the-knee amputations because of infected ulcers of the feet.

She uses a wheelchair for ambulation. Ten years ago, she underwent three-vessel coronary artery bypass grafting. She

has smoked one-half pack of cigarettes daily for 60 years. She drinks one shot of whiskey nightly. She is thin and appears

ill and disheveled. Her temperature is 37.2°C (99.0°F), pulse is 80/min, respirations are 20/min, and blood pressure is

120/80 mm Hg. Pulse oximetry on 2 L/min of oxygen by nasal cannula shows an oxygen saturation of 95%. Physical

examination shows temporal wasting. There are scattered ecchymoses over the abdomen and all extremities. No other

abnormalities are noted. Which of the following is the most appropriate initial history to obtain from this patient?

(A) Abnormal bleeding

(B) Diet

(D) Respiratory symptoms

(E) Urinary symptoms

68. A healthy 26-year-old man with red-green color blindness marries a woman whose father also has red-green color

blindness. A pedigree is shown. Which of the following best predicts the risk that a son of this couple will be affected?

(A) 0%

(B) 25%

(D) 75%

(E) 100%

69. A 25-year-old woman comes to the physician because of a long history of pain with menses. The pain occurs on the first

day of her 5-day menstrual period and lasts all day. She rates the pain as 10 on a 10-point scale. The most appropriate

initial pharmacotherapy to relieve this patient's pain has which of the following mechanisms of action?

(A) Inhibition of estrogen synthesis

(B) Inhibition of 11β-hydroxylase activity

(D) Stimulation of follicle-stimulating hormone synthesis

(E) Stimulation of luteinizing hormone synthesis

70. A 56-year-old woman comes to the physician because of a 2-year history of recurrent urinary tract infections

accompanied by left flank pain. Physical examination shows no abnormalities. Renal ultrasonography shows left-sided

hydronephrosis. A T2-weighted coronal MRI of the abdomen is shown; the arrow indicates the hydronephrosis. The left

renal collecting system is most likely obstructed at which of the following anatomic locations in this patient?

(A) Bladder neck

(B) Mid ureter

(D) Ureteropelvic junction

(E) Ureterovesical junction

71. A randomized clinical trial is conducted to compare wound healing and cosmetic differences between two surgical

procedures for closing skin wounds following cesarean delivery. A total of 1000 women undergoing cesarean delivery

during a 6-month period are enrolled in the study, which was 85% of the total number of patients undergoing the

procedure. The results show a wound infection rate of 12 cases per 1000 women for Procedure A and 18 cases per 1000

women for Procedure B. Which of the following is the best estimate of the absolute risk reduction for wound infection

following Procedure A compared with Procedure B?

(A) (18/1000) – (12/1000)

(B) 0.85 × (12/1000)

(D) [0.85 × (18/1000–12/1000)]

(E) [(1.2/100) – (1.8/100)]/(1.8/100)

72. A 52-year-old man is admitted to the hospital because of a 2-hour history of vomiting bright red blood. His pulse is

125/min, and blood pressure is 90/60 mm Hg. Physical examination shows jaundice and visible blood vessels

surrounding the umbilicus. CT scans of the abdomen are shown. To decrease portal venous pressure in this patient, it is

most appropriate to place a shunt between the portal vein and which of the following additional vessels?

(A) Inferior mesenteric vein

(B) Inferior vena cava

(D) Splenic vein

(E) Superior mesenteric vein

73. A 58-year-old man with chronic obstructive pulmonary disease comes to the clinic with his wife for a follow-up

examination. He has smoked one pack of cigarettes daily for 35 years. He has tried to quit smoking twice but was

unsuccessful both times. At today’s visit, when the physician asks the patient about smoking cessation, he says he is not

ready to do so. The patient’s wife states her husband’s smoking makes her cough and gives her chest tightness. Which

of the following is the most appropriate physician statement?

(A) "Are there any reasons why you might want to quit smoking?"

(B) "Are you aware that your lung condition is chronic at this point?"

(D) "The majority of your health issues would improve if you quit smoking."

(E) "Why haven't you been able to stay off cigarettes?"

74. Seven days after admission to the psychiatric unit for treatment of eating disorders, a hospitalized 20-year-old woman

has a 2-day history of moderate mouth pain on the inside of both cheeks. She also reports feeling "worthless and fat."

Fluoxetine was started on admission. She appears distressed. She is 170 cm (5 ft 7 in) tall and weighs 77 kg (170 lb);

BMI is 27 kg/m

. Vital signs are within normal limits. Physical examination shows bilateral swelling of the parotid and

submandibular glands, discoloration of several teeth, and scarring on the dorsum of the right hand. Mental status

examination shows no suicidal ideation or intent. Results of laboratory studies are within the reference ranges. A

medication with which of the following mechanisms of action is most appropriate to treat this patient's current

symptoms?

(A) Binding to muscarinic acetylcholine receptors

(B) Binding to nicotinic acetylcholine receptors

(D) Inhibition of protein synthesis via loss of DNA helical structure

(E) Interference with bacterial wall synthesis

75. A 35-year-old woman, gravida 2, para 1, at 15 weeks’ gestation is brought to the hospital in active labor. The physician

care team confers and determines that the birth cannot be prevented and that the fetus will not survive. After explaining

this fact to the patient, the patient says, "I know it is a long shot, but I still want my baby resuscitated and everything

done to save him." After empathizing with the patient, which of the following is the most appropriate initial response by

the physician?

(A) "I will ask for a second opinion."

(B) "I will call the father of the baby to get his opinion as well."

(D) "I will do everything I can to save the baby."

(E) "I’m very sorry, but the baby will not survive."

76. A 48-year-old man who is a contractor interpreter working for the military at a US outpost in Afghanistan comes to the

medical clinic because of a 20-day history of nonhealing, painless ulcers on his neck and arms. The lesions enlarged

over time and began to express clear fluid, eventually forming shallow ulcers. When the symptoms began, he was

sleeping on a mattress on the floor in an old building without air conditioning where the ambient temperature ranged

from 21.1°C (70.0°F) to 43.3°C (110.0°F). He originally attributed the lesions to bug bites. Vital signs are within normal

limits. Physical examination shows six 2-cm, papular lesions scattered over the neck and upper extremities; each lesion

has a 0.6-cm ulcer in the center. There is no pus or exudate. Which of the following vectors is the most likely source of

the lesions in this patient?

(A) Flea

(B) Mosquito

(D) Spider

(E) Tick

77. A 17-year-old boy is brought to the clinic for a follow-up examination. He has been evaluated for three episodes of full-

body weakness at the ages of 13, 16, and 17 years. Each episode occurred when he lay down after playing in a football

scrimmage. The weakness improved spontaneously during the next 6 hours; he was asymptomatic by the time he was

evaluated by medical personnel. The patient attributes the episodes to eating "a lot of pasta and salty foods" prior to

playing football. Results of a complete blood count and comprehensive metabolic profile following each episode have

been within the reference ranges. He has no history of serious illness and takes no medications. Vital signs are within

normal limits. Physical and neurologic examinations disclose no abnormalities. Which of the following serum

concentrations is most likely to be abnormal if measured during one of this patient's episodes?

(A) Calcium

(B) Chloride

(D) Potassium

(E) Sodium

78. A 3-day-old female newborn is brought to the hospital because of a yellowish, milky fluid leaking from both nipples.

She was delivered at term to a 20-year-old woman. Pregnancy and delivery were uncomplicated. Examination of the

newborn is otherwise unremarkable. Which of the following hormones is the most likely cause of this finding?

(A) Maternal estrogen

(B) Maternal progesterone

(D) Newborn estrogen

(E) Newborn progesterone

(F) Newborn prolactin

79. A 74-year-old man comes to the office for a follow-up examination 1 month after he was discharged from the hospital

following a cardiac valve replacement operation. Physical examination shows a healing median sternotomy wound. A

prosthetic click is heard. PA and lateral chest x-rays are shown; the arrows indicate the replaced cardiac valve. Based

on these findings, which of the following cardiac valves was most likely replaced in this patient?

(A) Aortic

(B) Mitral

(D) Tricuspid

80. A 37-year-old man who is a carpenter is brought to the emergency department 45 minutes after the sudden onset of fever,

shortness of breath, and palpitations. Four days ago, he sustained a puncture wound to his left hand; he treated the wound

with antibacterial cream and a bandage. His temperature is 39°C (102.2°F), pulse is 120/min, respirations are 28/min,

and blood pressure is 100/60 mm Hg. Examination of the left hand shows diffuse swelling, erythema, and a 2-cm,

necrotic puncture wound. His leukocyte count is 14,000/mm

. Arterial blood gas analysis on room air shows a PCO

less than 32 mm Hg. Which of the following is the most likely infectious agent in this patient?

(A) Clostridium tetani

(B) Mycobacterium abscessus

(D) Pseudomonas aeruginosa

(E) Staphylococcus aureus

USMLE STEP 1 SAMPLE TEST QUESTIONS

BLOCK 3, ITEMS 81-119

81. A 45-year-old woman comes to the office for a follow-up examination 2 weeks after she sustained a vertebral fracture at

L1. The fracture occurred spontaneously and there is no history of trauma to the area or other fractures. She gained 27

kg (60 lb) during the 6 months before the fracture occurred. Her only medication is hydromorphone as needed for pain.

She is 163 cm (5 ft 4 in) tall and now weighs 100 kg (220 lb); BMI is 38 kg/m

. Temperature is 37.0°C (98.6°F), pulse

is 86/min, respirations are 12/min, and blood pressure is 145/98 mm Hg. Physical examination shows central obesity

and purple striae over the abdomen bilaterally. The lower extremities appear thin. Results of laboratory studies are

shown:

Plasma

Renin activity

5.0 ng/mL/h (N=0.6–4.0)

Metanephrine

0.3 nmol/L (N<0.4)

Serum

Cortisol, random

43 μg/dL

Adrenocorticotropic hormone

120 pg/mL (N<120)

Aldosterone

8 ng/dL (N=2–9)

Urine 24-hour free cortisol excretion

340 µg/24 h (N=3.5–45)

The most likely cause of the fracture in this patient is an increase in which of the following processes?

(A) Calcium absorption

(B) Calcium excretion

(D) Osteoclast proliferation

(E) Phosphorus absorption

(F) Phosphorus excretion

82. A 25-year-old woman comes to the emergency department because of a 3-hour history of fever, severe headache, light-

headedness, dizziness, shaking chills, and muscle aches. Five hours ago, she was diagnosed with Lyme disease and

began doxycycline therapy. She has no other history of serious illness and takes no other medications. Menses occur at

regular 28-day intervals. She is currently menstruating and using a tampon. She appears anxious. Temperature is 37.0°C

(98.6°F), pulse is 120/min, respirations are 30/min, and blood pressure is 90/60 mm Hg. Pulse oximetry on room air

shows an oxygen saturation of 94%. Physical examination shows flushing and diaphoresis. Cardiopulmonary

examination shows no other abnormalities. Which of the following is the most likely mechanism of this patient’s current

condition?

(A) Exacerbation of infection by Borrelia burgdorferi

(B) Infection-mediated sepsis

(D) Release of bacterial products producing acute inflammation

(E) Secretion of bacterial endotoxins

83. A newborn delivered at 36 weeks' gestation to a 22-year-old woman, gravida 1, para 1, has difficulty feeding and

listlessness. The mother received no prenatal care. Spontaneous vaginal delivery was uncomplicated. The mother's only

medication was a prenatal vitamin. The newborn's length is 49 cm (19 in; 39th percentile), and weight is 3100 g (6 lb

13 oz; 30th percentile); head circumference is 33 cm (13 in; 12th percentile). Temperature is 37.0°C (98.6°F), pulse is

134/min, respirations are 38/min, and blood pressure is 73/50 mm Hg. Physical examination shows ambiguous genitalia.

Results of serum studies are shown:

133 mEq/L

5.0 mEq/L (N=3.2–5.5)

–

103 mEq/L

HCO

–

17 mEq/L

Glucose

42 mg/dL (N=30–60)

The most appropriate pharmacotherapy for this patient targets which of the following receptors?

(A) Adrenocorticotropic hormone

(B) Aldosterone

(D) Gonadotropin-releasing hormone

(E) Growth hormone

84. A 60-year-old woman is brought to the emergency department because of a 4-day history of fever, joint aches, and rash.

Three weeks ago, she was admitted to the hospital for treatment of Staphylococcal aureus endocarditis. She has received

21 days out of a prescribed 42-day course of intravenous oxacillin. Currently, she appears to be in mild distress.

Temperature is 38.0°C (100.4°F), pulse is 115/min, respirations are 24/min, and blood pressure is 120/70 mm Hg. Pulse

oximetry on room air shows an oxygen saturation of 97%. Physical examination shows a diffuse maculopapular rash

over the trunk and upper and lower extremities. There is no pus or erythema at the skin insertion site of the peripherally

inserted central catheter line initially placed on the day of hospital discharge. Results of laboratory studies are shown:

Hemoglobin

11.1 g/dL

Hematocrit

33%

Leukocyte count

12,100/mm

Segmented neutrophils

78%

Eosinophils

Lymphocytes

Monocytes

Platelet count

341,000/mm

Serum

133 mEq/L

6.5 mEq/L

−

100 mEq/L

HCO

−

15 mEq/L

Urea nitrogen

65 mg/dL

Glucose

96 mg/dL

Creatinine

5.7 mg/dL

Urine microscopy shows eosinophils and WBC casts. Which of the following is the most likely underlying cause of this

patient's condition?

(A) Collapsing focal segmental glomerulosclerosis

(B) Glomerular hypertrophy with hemorrhage and necrosis

(D) Mesangial expansion with glomerular basement membrane thickening

(E) Proximal tubular dilation with loss of brush border

85. A 48-year-old man comes to the physician requesting treatment for alcohol withdrawal. He reports a 30-year history of

consuming 6 to 10 beers daily. He has had two citations for driving while intoxicated. He has previously experienced

alcohol-associated seizures and withdrawal symptoms. His vital signs are within normal limits. Physical examination

shows palmar erythema. The most appropriate pharmacotherapy in this patient most likely has which of the following

mechanisms?

(A) Blockade of dopamine receptors

(B) Decreased activity of dopamine transporters

(D) Increased GABA transaminase activity

(E) Inhibition of glutamate release

(F) Inhibition of serotonin reuptake

(G) Opening of glutamate channels

(H) Stimulation of 5-hydroxytryptophan receptors

86. A 6-year-old girl is brought to the office because of two episodes of vaginal bleeding during the past 2 months. She has

no history of serious illness and receives no medications. She does not appear to be in distress. She is at the 60th

percentile for height, 40th percentile for weight, and 35th percentile for BMI. Vital signs are within normal limits.

Physical examination discloses palpable breast buds and minimal coarse, pigmented hair on the labia. The remainder of

the examination shows no abnormalities. Results of serum studies are shown:

Thyroid-stimulating hormone

2.1 mU/mL (N=0.5–5.0)

Testosterone

680 ng/dL (N=0.17–0.7)

Adrenocorticotropic hormone

18 pg/mL (N=9–52)

Estradiol

185 pg/mL (N<20)

Follicle-stimulating hormone

15 mIU/mL (N<6.7)

Luteinizing hormone

3.0 mIU/mL (N<0.2)

Which of the following is the most likely cause of this patient's condition?

(A) Central activation of neurons

(B) Ectopic prolactin secretion

(D) Germline GNAS activating mutation

(E) 21-Hydroxylase deficiency

87. A previously healthy 64-year-old man is brought to the emergency department 3 hours after the sudden onset of severe

flank pain. He has no history of similar pain or serious illness. He takes no medications. He appears to be in distress.

His pulse is 100/min, and blood pressure is 168/92 mm Hg. Physical examination shows a soft abdomen with left-sided

tenderness. Urinalysis shows microscopic hematuria. A CT scan of the abdomen shows a small ureteric calculus.

Analgesic therapy is initiated and the pain resolves 1 hour later. The urine is then strained and a uric acid calculus is

found. Which of the following processes is most likely impaired in this patient?

(A) Bile salt metabolism

(B) Cholesterol metabolism

(D) Purine metabolism

(E) Urea cycle

88. A 65-year-old woman has congestive heart failure for which she is treated with an appropriate drug regimen including

an ACE inhibitor. Because of insufficient improvement in her symptoms of dyspnea on exertion and edema, the

physician prescribes a second agent that results in hyperkalemia. This adverse effect most likely resulted from a drug

that targets which of the following labeled locations in the diagram of a nephron?

(A) A

(B) B

(D) D

(E) E

89. Patient Information

Age: 34 years

Gender: M, self-identified

Race/Ethnicity: unspecified

Site of Care: office

The patient presents because of a 2-year history of recurrent abdominal pain and diarrhea; he also has had an 11-kg (25-

lb) weight loss during this period. He describes his stools as copious, loose, oily and foul-smelling. His bowel movements

occur six to eight times daily, often immediately after meals, and are associated with bloating and cramping. Since the

age of 21 years, he has had several episodes of acute pancreatitis. He has not had fevers or bloody stools. He is 178 cm

(5 ft 10 in) tall and weighs 57 kg (125 lb); BMI is 18 kg/m

. Physical examination shows a flat abdomen with hyperactive

bowel sounds and diffuse mild tenderness. Digital rectal examination shows no abnormalities. Test of the stool for occult

blood is negative. Treatment with which of the following enzymes is most likely to be beneficial in this patient?

(A) Amylase

(B) Lactase

(D) Protease

(E) Tryptase

90. A previously healthy 65-year-old woman comes to the physician because of several episodes of fainting during the past

2 months. Each episode lasted several minutes. Her pulse is 82/min, respirations are 20/min, and blood pressure is

135/87 mm Hg. Cardiac examination shows S

and S

. Echocardiography shows a pedunculated intracardiac mass. The

lesion is resected. A photomicrograph of the resected lesion is shown. This lesion was most likely obtained from which

of the following locations?

(A) Interventricular septum

(B) Left atrium

(D) Right atrium

(E) Right ventricle

91. A 4-year-old girl with type 1 diabetes mellitus is brought to the emergency department by her father because of a 4-hour

episode of restlessness, sweating, and confusion that occurred during the night. Yesterday, he allowed her to eat cupcakes

and cotton candy at a county fair. At her bedtime that evening, he increased her dose of subcutaneous intermediate-

acting and long-acting insulin. Her symptoms began 6 hours later, then resolved spontaneously. After being informed

this morning of this nighttime episode, the mother insisted the father bring the patient to the hospital. On arrival, the

patient is alert. Her vital signs are within normal limits. Examination shows no abnormalities. Her fingerstick blood

glucose concentration is 72 mg/dL. Urinalysis is negative for glucose and ketones. Which of the following is the most

likely explanation for this patient's nighttime symptoms?

(A) Hyperglycemia caused by increased glucose consumption

(B) Hyperglycemia caused by increased glycogen metabolism

(D) Hypoglycemia caused by excess exogenous insulin

(E) Hypoglycemia caused by excessive renal glucose loss

(F) Hypoglycemia caused by increased glucagon secretion

(G) Nightmare disorder

(H) Sleep terror disorder

92. A 75-year-old woman comes to the physician because of a 3-year history of pain in her wrists and hands. She says that

the pain has become more severe during the past 3 months. She has difficulty buttoning her coat because of the pain.

Physical examination shows the findings in the photograph. Which of the following additional hand findings is most

likely in this patient?

(A) Cortical thinning

(B) Degenerative changes of the cartilage

(D) Neutrophilic infiltration of the synovium

(E) Thickening of the synovium with pannus

93. A 66-year-old man who was recently diagnosed with Parkinson disease comes to the physician for a follow-up

examination. Carbidopa-levodopa therapy was initiated at the time of diagnosis. The patient tells the physician that he

still has episodes during which he "freezes." He has a clumsy gait, and there is rigidity of his upper extremities and

hands. An adjunct therapy designed to inhibit which of the following enzymes is most likely indicated in this patient?

(A) Aromatic L-amino acid decarboxylase

(B) Dopamine β-hydroxylase

(D) Phenylethanolamine N-methyltransferase

(E) Tyrosine hydroxylase

94. A 2-week-old male newborn is brought to the office for a well-child examination. He was delivered following an

uncomplicated, spontaneous vaginal delivery at 41 weeks' gestation. The mother has no history of serious illness and

did not receive prenatal care. Her only medication is a prenatal vitamin. She has consumed large amounts of vodka

nightly for 10 years. Which of the following examination findings is most likely to be present in this patient?

(A) Hypospadias

(B) Limb hypoplasia

(D) Short palpebral fissures

(E) Spasticity

95. Patient Information

Age: 16 years

Gender: M, self-identified

Race/Ethnicity: Hispanic, self-identified

Site of Care: clinic

History

Reason for Visit/Chief Concern: "I haven't started puberty yet."

History of Present Illness:

• absence of pubic and facial hair

• small penis and testicle size

Past Medical History:

• no serious illness

Medications:

• none

Allergies:

• no known drug allergies

Psychosocial History:

• does not smoke cigarettes, drink alcoholic beverages, or use other substances

Physical Examination

Temp

Pulse

Resp

Sat

BMI

36.0°C

76/min

13/min

108/61 mm Hg

98%

184 cm

90 kg

27 kg/m

(96.8°F)

on RA

(6 ft)

(198 lb)

90th %ile

97th %ile

94th %ile

• Appearance: long extremities

• Skin: no facial or axillary hair

• HEENT: PERRLA

• Chest: bilateral gynecomastia

• Pulmonary: clear to auscultation

• Cardiac: normal S

and S

• Abdominal: normoactive bowel sounds; no tenderness to palpation; no hepatosplenomegaly

• Genitourinary: small testicular and penile size; minimal pubic hair; SMR 2

• Neurologic: muscle strength 5/5 throughout

Diagnostic Studies:

Serum

Follicle-stimulating hormone

45 mIU/mL

Luteinizing hormone

34 mIU/mL

Testosterone

45 ng/dL (N=270–950)

TSH

2.2 μU/L

Question: Which of the following is the most likely underlying cause of this patient's condition?

(A) Constitutional delay in puberty

(B) Hypoplasia of hypothalamic gonadotropin-releasing hormone neurons

(D) Mutation in the 21-hydroxylase gene

(E) Nondisjunction of X chromosome during meiosis

96. A 57-year-old man with chronic low back pain comes to the office for a routine health maintenance examination. The

patient's last visit to the office was 2 years ago, and today he says he is "doing about the same," except for an

unintentional 10-kg (22-lb) weight gain. He attributes the weight gain to inability to exercise because of his back pain,

and he is now considering applying for disability benefits. He was evaluated by a back pain specialist 3 months ago and

underwent an MRI of the lumbar spine at that time; however, he says he did not understand the specialist's explanation

regarding the MRI results and requests further explanation. Medical history also is remarkable for hyperlipidemia,

seasonal allergies, and opioid use disorder; he has not used opioids of any kind since he stopped prescription oxycodone

use 5 years ago. Routine medications are atorvastatin, diclofenac, and loratadine. He develops skin flushing when taking

niacin, but he has no known drug allergies. He has smoked two packs of cigarettes daily for 25 years. He previously

drank two beers daily, but he has not consumed any alcoholic beverages or used any recreational drugs for the past 5

years. He is 178 cm (5 ft 10 in) tall and weighs 104 kg (230 lb); BMI is 33 kg/m

. Vital signs are within normal limits;

blood pressure is 128/70 mm Hg. While standing, the patient leans forward slightly. Range of motion on lumbar

extension and flexion is decreased. The remainder of the examination discloses no abnormalities. Results of fasting

serum studies are shown:

140 mEq/L

4.7 mEq/L

−

100 mEq/L

HCO

−

24 mEq/L

Urea nitrogen

15 mg/dL

Creatinine

0.7 mg/dL

Cholesterol

Total

230 mg/dL

HDL

60 mg/dL

LDL

154 mg/dL

Triglycerides

80 mg/dL

MRI of the lumbar spine is shown. Which of the following factors in this patient's history most strongly contributed to

the MRI findings?

(A) Alcohol consumption

(B) Cigarette smoking

(D) Loratadine use

(E) Opioid use

97. A 15-year-old boy is brought to the office by his parents to discuss results of a biopsy done 3 days ago for a rapidly

enlarging neck mass. He first noted the mass 1 month ago. Two weeks ago, he was evaluated for an episode of prolonged

epistaxis and was found to have a right ear effusion, which was treated with amoxicillin-clavulanic acid. He has no other

history of serious illness and takes no medications. Height is at the 10th percentile, weight is at the 50th percentile, and

BMI is at the 75th percentile. Vital signs are within normal limits. Physical examination shows a right ear effusion and

a 4-cm, firm mass in the right posterior triangle of the neck. Results of a biopsy specimen show squamous epithelium

with indistinct cell margins, enlarged atypical nuclei, and absent keratin formation. Which of the following infectious

agents is the most likely underlying cause of this patient's current condition?

(A) Cytomegalovirus

(B) Epstein-Barr virus

(D) Human herpesvirus 8

98. A 48-year-old woman with type 2 diabetes mellitus comes to the physician for a follow-up examination. Current

medications are metformin and once-daily insulin. She travels frequently and works long hours. She says that her meals

are usually fast food. She leads a sedentary lifestyle. She often forgets to measure her blood glucose concentration. Her

last hemoglobin A

was measured as 8.4%. Which of the following is the most appropriate action by the physician to

help this patient improve her diabetic control?

(A) Create an exercise regimen for the patient

(B) Explore barriers to diet adherence

(D) Increase the patient's metformin dosage

(E) Measure the patient's blood glucose concentration

(F) Order measurement of the patient's microalbumin concentration

(G) Refer the patient to a nutritionist

99. A 74-year-old woman with a history of coronary artery disease is brought to the emergency department 30 minutes after

the sudden onset of crushing chest pain. Her pulse is 120/min, and systolic blood pressure is 70 mm Hg. An ECG shows

sinus rhythm with ST elevation in leads V

through V

. The physician plans to administer a drug to increase the patient's

blood pressure without increasing her pulse. Which of the following drugs is most appropriate for this patient?

(A) Dopamine

(B) Epinephrine

(D) Norepinephrine

(E) Phenylephrine

100. A 2-month-old girl is admitted to the hospital because of severe pneumonia. She has a history of mucocutaneous

candidiasis and chronic diarrhea. Her pulse is 160/min, and respirations are 40/min. Crackles are heard over both lung

fields. Her leukocyte count is 5400/mm

(N=5000–19,500), with 86% segmented neutrophils, 6% lymphocytes, and 8%

monocytes. Immunologic testing of a specimen obtained via bronchoscopy is positive for Pneumocystis jirovecii. Flow

cytometry shows normal concentrations of natural killer cells but no T or B lymphocytes in the peripheral blood. Results

of a polymerase chain reaction test of the immunoglobulin V(D)J regions from a bone marrow specimen show an absence

of characteristic rearrangements. The most likely cause of these findings is an alteration of which of the following?

(A) Bruton tyrosine kinase

(B) CD40 ligand

(D) NADPH oxidase

(E) Recombination-activating gene 1 (RAG1) and RAG2

101. A 25-year-old woman, gravida 1, para 1, comes to the office because of a 2-week history of palpitations and heat

intolerance. She delivered her child 3 months ago following an uncomplicated pregnancy and delivery. She is breast-

feeding. She has no history of serious illness and takes no medications. She is 163 cm (5 ft 4 in) tall and weighs 54 kg

(120 lb); BMI is 21 kg/m

. Temperature is 37°C (98.6°F), pulse is 106/min, respirations are 20/min, and blood pressure

is 124/68 mm Hg. Examination shows moist palms and bilateral lid lag. No exophthalmos is noted. The thyroid gland

is enlarged and nontender. No murmurs are heard on cardiac examination. Deep tendon reflexes are 3+. Serum studies

show an undetectable TSH concentration, thyroxine (T

) concentration of 20 μg/dL, and triiodothyronine (T

)

concentration of 275 ng/dL. Which of the following is the most likely mechanism of this patient's symptoms?

(A) Activation of mutations of TSH receptors

(B) Increased serum thyroglobulin concentration

(D) Lymphocytic infiltration of the thyroid

(E) Presence of TSH receptor autoantibodies

102. A 53-year-old woman comes to the office because of a 6-year history of stiffness and pain of her hands. She has difficulty

buttoning her clothes because of the symptoms. She takes no medications. Physical examination shows the findings in

the photograph. An abnormality of which of the following is most likely to confirm the diagnosis in this patient?

(A) Anti-citrullinated peptide antibody

(B) Antimitochondrial antibody assay

(D) Precursor of the erythroid cell line

(E) Precursor of the thrombopoietic line

103. A 73-year-old woman comes to the emergency department because of a 6-hour history of severe abdominal pain. She

has chronic atrial fibrillation and underwent placement of a prosthetic mitral valve 4 years ago. Her pulse is 120/min

and irregularly irregular, and blood pressure is 80/60 mm Hg. Arteriography shows an embolus in the superior

mesenteric artery lodged just beyond the patent middle colic artery. A laparotomy is done. During this procedure, which

of the following segments of the abdominal viscera is most likely to appear normal?

(A) Ascending colon

(B) Distal ileum

(D) Proximal ileum

(E) Proximal jejunum

104. A 2-year-old boy is brought to the physician because of failure to thrive. He also has had loose, fatty, foul-smelling stools

and a cough during the past 2 weeks. He is at the 30th percentile for height and 10th percentile for weight. Physical

examination shows no other abnormalities. Laboratory studies show steatorrhea and a sweat chloride concentration of

80 mmol/L. A chest x-ray shows hyperinflation. Sputum culture grows Haemophilus influenzae and Staphylococcus

aureus. Secretion of which of the following substances is most likely to be decreased in this patient?

(A) Bicarbonate

(B) Gastric acid

(D) Insulin

(E) Intrinsic factor

105. A 73-year-old man is brought to the emergency department by his family 1 hour after he walked into the left side of a

door frame when leaving his bedroom and then tripped over a chair that was on his left side. Visual field testing shows

left lower quadrantanopia. When tactile stimuli are presented on both the left and right sides simultaneously, the patient

correctly identifies only the ones on the right. Further examination shows no motor or language deficits. Proprioception

is intact. This patient most likely has a brain lesion in which of the following lobes?

(A) Left frontal

(B) Left parietal

(D) Right frontal

(E) Right parietal

(F) Right temporal

106. A 10-year-old boy is brought to the physician because of a 3-week history of nosebleeds and easy bruisability. His older

brother has had similar episodes. He is at the 30th percentile for height and weight. Physical examination shows nasal

and gingival bleeding and several ecchymoses over the trunk and upper and lower extremities in various stages of

healing. Laboratory studies show a platelet count of 300,000/mm

(N=150,000–400,000). Platelet adhesion testing

shows a normal response to ristocetin, but aggregation does not occur in response to thrombin; platelet morphology is

normal. Prothrombin time and activated partial thromboplastin time are within the reference ranges. A defect in which

of the following is the most likely cause of the findings in this patient?

(A) Factor VII (proconvertin)

(B) Fibrinogen

(D) Granule storage pool

(E) von Willebrand factor

107. A previously healthy 45-year-old woman who works as a park ranger comes to the physician because of a 1-week history

of shortness of breath, even at rest. She has lived in the mountains at 10,000 feet above sea level for 2 years; the

physician’s office is located at sea level. Her pulse is 85/min, respirations are 18/min, and blood pressure is 125/90 mm

Hg. Physical examination while sitting upright shows jugular venous distention and 2+ pedal edema. During the past 2

years, which of the following has most likely decreased in this patient?

(A) Height of P waves in lead I of the patient's ECG

(B) Height of R waves in lead V

of the patient's ECG

(D) Pulmonary vascular resistance

(E) Right ventricular diastolic compliance

(F) Right ventricular wall thickness

108. A 5-year-old girl is brought to the office by her mother because of a 6-hour history of bloody diarrhea. She is interactive

and in no acute distress. Her blood pressure is 90/55 mm Hg. Abdominal examination shows normoactive bowel sounds.

Stool cultures are obtained, and the patient's mother is advised to give the girl plenty of fluids. Five days later, the patient

develops decreased urine output and is brought back to the office. Her blood pressure is now 135/88 mm Hg. Physical

examination shows pallor. Laboratory studies show:

Hemoglobin

8.5 g/dL (N=11–15)

Hematocrit

26% (N=28%–45%)

Platelet count

45,000/mm

(N=150,000–400,000)

Serum creatinine

3.3 mg/dL (N=0.3–0.7)

Which of the following infectious agents is the most likely cause of these findings?

(A) Campylobacter jejuni

(B) Escherichia coli

(D) Salmonella enterica serovar enteritidis

(E) Yersinia pestis

109. A 78-year-old woman is admitted to the intensive care unit because of diverticulitis complicated by Escherichia coli

sepsis. Treatment with ciprofloxacin is started. Three days later, her serum creatinine concentration has increased from

0.7 mg/dL on admission to 1.3 mg/dL. Urinalysis shows muddy brown casts. The most likely cause of the findings in

this patient is ischemia of which of the following structures?

(A) Bowman capsule

(B) Glomerulus

(D) Proximal tubule

(E) Renal vein

110. A 19-year-old man who is a college freshman comes to the office because of a 4-day history of tender, swollen glands.

He also has a 6-day history of fever, malaise, and decreased appetite. His temperature is 38.7°C (101.7°F). Physical

examination shows swelling of the parotid glands. Which of the following infectious agents is the most likely cause of

these findings?

(A) Epstein-Barr virus

(B) Hepatitis B virus

(D) Mumps virus

(E) Rubella virus

111. A 34-year-old woman with myasthenia gravis comes to the emergency department because of a 2-day history of

increasing weakness, shortness of breath, and abdominal cramping. Current medications are prednisone and

pyridostigmine. Her temperature is 37°C (98.6°F), pulse is 45/min, and respirations are 25/min and shallow. Her voice

is soft and hypernasal, and she coughs weakly when swallowing water. Breath and heart sounds are normal. Pulmonary

testing shows inability to generate a normal negative inspiratory force during forced inspiration. The abdomen is soft

and nontender, with increased bowel sounds. Muscle strength is 4/5 diffusely, with severe, continuous, and diffuse

fasciculations. Deep tendon reflexes are sluggish, but symmetric. Which of the following is the most likely cause of this

patient's weakness?

(A) Aspiration pneumonia

(B) Guillain-Barré syndrome

(D) Motor neuron disease

(E) Pyridostigmine overdose

112. A 35-year-old woman comes to the office because she has had three first-trimester spontaneous abortions during the past

3 years. Physical examination shows no abnormalities. Laboratory studies show no endocrine abnormalities.

Chromosomal analysis shows a paracentric inversion of the long arm of chromosome 1. Which of the following best

describes this patient’s risk for early spontaneous abortions and a liveborn child with aneuploidy?

Risk for Early

Risk for Liveborn

Spontaneous Abortions

Child With Aneuploidy

(A)

High

high

(B)

High

low

(C)

Low

high

(D)

Low

low

113. A 25-year-old man comes to the office because of a 4-hour history of irritability, restlessness, tremor, and palpitations.

He is a known user of amphetamines. His pulse is 120/min, respirations are 25/min, and blood pressure is 150/100 mm

Hg. Physical examination shows no abnormalities. The most likely cause of this patient's symptoms is sympathomimetic

activity arising from which of the following?

(A) Decreased intracellular metabolism of biogenic amines

(B) Decreased monoamine oxidase activity

(D) Increased intracellular metabolism of biogenic amines

(E) Increased presynaptic receptor activation

(F) Increased release of biogenic amines

114. A 14-year-old boy is brought to the office by his mother because of a 1-week history of seizures and difficulty walking.

Physical examination shows decreased sensation over the hands and feet and generalized weakness. He walks with an

ataxic gait. A muscle biopsy specimen shows coarsely granular fibers that stain red with Gomori trichrome stain. This

patient most likely has a genetic defect that most directly affects the synthesis of which of the following?

(A) ATP

(B) Creatine phosphate

(D) NADH

(E) Pyruvate

115. A 72-year-old man is brought to the office because of a 6-month history of increasing fatigue and a 1-month history of

numbness of his feet. Physical examination shows marked pallor. Proprioception and sensation to vibration are decreased

in the lower extremities. Laboratory studies show:

Hemoglobin

7.6 g/dL

Mean corpuscular volume

117 μm

Reticulocyte count

Serum vitamin B

(cobalamin)

23.6 pg/mL (N=200–900)

Histopathology of a gastric mucosal biopsy specimen shows atrophic gastritis with extensive lymphocyte infiltration.

Serologic studies will most likely show autoantibodies to which of the following labeled cell types in the

photomicrograph of normal mucosa or to one of its secretory products?

116. A 66-year-old woman comes to the office for a follow-up examination 1 month after being diagnosed with paroxysmal

atrial fibrillation. Appropriate pharmacotherapy was initiated at that time, and normal sinus rhythm was restored. Her

pulse is 76/min, and blood pressure is 132/86 mm Hg. Physical examination shows no abnormalities. The ECGs shown

represent before (solid line) and after (dashed line) administration of the antiarrhythmic drug. Which of the following

drugs was most likely prescribed?

(A) Amiodarone

(B) Digoxin

(D) Phenytoin

(E) Verapamil

117. A 4-year-old boy develops fever 3 weeks after being admitted to the hospital for induction chemotherapy for treatment

of acute lymphoblastic leukemia. Chemotherapy medications are L-asparaginase, dexamethasone, doxorubicin, and

vincristine. His temperature is 38.2°C (100.8°F), pulse is 122/min, and respirations are 24/min. Physical examination

shows pallor, alopecia, and ulcerations over the gums. A central venous catheter with entry site in the right upper chest

is present but has no surrounding erythema. A blood culture grows gram-negative rods after 36 hours. Which of the

following underlying mechanisms is the most likely cause of this patient's susceptibility to infection?

(A) Deficiency of terminal complement

(B) Hypogammaglobulinemia

(D) Inhibition of tumor necrosis factor α function

(E) Neutropenia

118. A 6-year-old boy with acute lymphoblastic leukemia is brought to the office for a follow-up examination. He is receiving

high-dose methotrexate therapy. A drug is added to the patient's medication regimen to decrease the toxicity of this

therapy to normal cells. The beneficial effect of this new drug on normal cells is most likely achieved by bypassing the

cellular requirement for which of the following enzymes?

(A) Dihydrofolate reductase

(B) Methionine synthase

(D) Thiamine pyrophosphate

(E) Thymidylate synthase

119. A screening test for breast cancer is administered to 1000 women with biopsy-proven breast cancer and to 1000 women

without breast cancer. The test results are positive for 250 of the subjects with breast cancer and 100 of the subjects

without breast cancer. The screening test is now to be used on a population of 100,000 women with a known prevalence

rate of breast cancer of 80 per 100,000. Which of the following is the expected number of false-positives?

(A) 20

(B) 80

(D) 9992

(E) 10,012

Block 1 (Questions 1–40)

1. ___ 11. ___ 21. ___ 31. ___

2. ___ 12. ___ 22. ___ 32. ___

3. ___ 13. ___ 23. ___ 33. ___

4. ___ 14. ___ 24. ___ 34. ___

5. ___ 15. ___ 25. ___ 35. ___

6. ___ 16. ___ 26. ___ 36. ___

7. ___ 17. ___ 27. ___ 37. ___

8. ___ 18. ___ 28. ___ 38. ___

9. ___ 19. ___ 29. ___ 39. ___

10. ___ 20. ___ 30. ___ 40. ___

Block 2 (Questions 41–80)

41. ___ 51. ___ 61. ___ 71. ___

42. ___ 52. ___ 62. ___ 72. ___

43. ___ 53. ___ 63. ___ 73. ___

44. ___ 54. ___ 64. ___ 74. ___

45. ___ 55. ___ 65. ___ 75. ___

46. ___ 56. ___ 66. ___ 76. ___

47. ___ 57. ___ 67. ___ 77. ___

48. ___ 58. ___ 68. ___ 78. ___

49. ___ 59. ___ 69. ___ 79. ___

50. ___ 60. ___ 70. ___ 80. ___

Block 3 (Questions 81–119)

81. ___ 91. ___ 101. ___ 111. ___

82. ___ 92. ___ 102. ___ 112. ___

83. ___ 93. ___ 103. ___ 113. ___

84. ___ 94. ___ 104. ___ 114. ___

85. ___ 95. ___ 105. ___ 115. ___

86. ___ 96. ___ 106. ___ 116. ___

87. ___ 97. ___ 107. ___ 117. ___

88. ___ 98. ___ 108. ___ 118. ___

89. ___ 99. ___ 109. ___ 119. ___

90. ___ 100. ___ 110. ___

ANSWER FORM FOR USMLE STEP 1 SAMPLE TEST QUESTIONS

Block 1 (Questions 1–40)

1. A

2. D

3. B

4. A

5. D

6. E

7. C

8. A

9. D

10. A

11. C

12. B

13. F

14. C

15. B

16. B

17. E

18. D

19. B

20. D

21. C

22. A

23. D

24. B

25. B

26. D

27. C

28. E

29. B

30. D

31. D

32. E

33. D

34. A

35. A

36. C

37. D

38. E

39. B

40. D

Block 2 (Questions 41–80)

41. B

42. A

43. C

44. C

45. C

46. B

47. A

48. A

49. B

50. D

51. D

52. B

53. A

54. B

55. E

56. D

57. C

58. E

59. E

60. E

61. D

62. A

63. C

64. B

65. A

66. C

67. C

68. C

69. C

70. D

71. A

72. B

73. A

74. A

75. E

76. C

77. D

78. C

79. A

80. E

Block 3 (Questions 81–119)

81. D

82. D

83. B

84. C

85. C

86. A

87. D

88. E

89. C

90. B

91. D

92. B

93. C

94. D

95. E

96. B

97. B

98. B

99. E

100. E

101. D

102. A

103. E

104. A

105. E

106. C

107. E

108. B

109. D

110. D

111. E

112. B

113. F

114. A

115. E

116. A

117. E

118. A

119. D

ANSWER KEY FOR USMLE STEP 1 SAMPLE TEST QUESTIONS