USMLE Sample Questions

Anatomy 

 

A professional musician visits his physician after a morning concert. He complains of painless swelling in his right cheek when he plays his tuba. Physical examination of the patient reveals slight facial asymmetry due to minor swelling on the right side of the face. The skin over the swelling is smooth without any secondary changes. Palpation reveals a soft and non-tender swelling. The oral opening is normal without any trismus. Further examination reveals swelling of the left buccal mucosa extending from the first to the third molar. Bedside ultrasound shows small areas of high echogenicity consistent with pneumoparotid. Which nerve is associated with motor function to prevent air from entering the affected duct in this patient?

A) V2 – Maxillary nerve

B) V3 – Mandibular nerve

C) CN VII – Zygomatic branch

D) CN VII – Buccal branch

E) CN VII – Marginal mandibular branch

A 59-year-old truck driver presents to the emergency department after returning from his usual week-long trucking trip with excruciating pain around his anus. The patient admits to drinking beer when not working and notes that his meals usually consist of fast food. He has no allergies, takes no medications, and his vital signs are normal. On examination, he was found to have a tender lump on the right side of his anus that measures 1 cm in diameter. The lump is bluish and surrounded by edema. It is visible without the aid of an anoscope. It is soft and tender with palpation. The rest of the man’s history and physical examination are unremarkable. Which vein drains the vessels responsible for the formation of this lump?

A) Internal hemorrhoids

B) Internal pudenal

C) Inferior mesenteric

D) Superior rectal

E) Middle rectal

Histology 



An 82-year-old woman presents to the emergency department after a ground-level fall. Imaging reveals diffuse trauma to the left humerus from the midshaft to the olecranon process with shearing of the periosteum. Over the next 2 weeks, the patient develops worsening pain at the site of injury. At her follow-up appointment with the orthopedic surgeon, she is found to have diffuse bone necrosis from the midshaft of the left humerus to the olecranon process with no involvement of the distal upper extremity structures. Which of the following structures must have been damaged to cause this recent development?

A) Haversian canal

B) Brachial artery

C) Volkmann’s canal

D) Ulnar nerve

E) Epiphyseal plate

A 3-year-old boy is diagnosed with an alpha-gal allergy, also known as mammalian meat allergy (MMA). This condition is mediated by a reaction to the carbohydrate, galactose-alpha-1,3-galactose. An experimental treatment has been developed to halt the N-linked oligosaccharide addition that occurs in the synthesis of this compound. Which of the following cellular structures is most likely targeted by this experimental drug?

A) Golgi apparatus

B) Rough endoplasmic reticulum

C) Sodium-potassium pump

D) Proteasome

E) Tumor suppressor p53

 

Pathology

A 70-year-old Caucasian woman presents with a 2-week history of blood-tinged sputum. Her past medical history is significant for peptic ulcer disease for which she underwent triple-drug therapy. She is a lifetime non-smoker and worked as a teacher before retiring at the age of 60 years. A review of systems is significant for a weight loss of 6.8 kg (15 lb) over the last 5 months. Her vitals include: blood pressure 135/85 mm Hg, temperature 37.7°C (99.9°F), pulse 95/min, and respiratory rate 18/min. Physical examination is unremarkable. A contrast CT scan of the chest shows an irregular mass in the peripheral region of the inferior lobe of the right lung. A CT-guided biopsy is performed and reveals malignant tissue architecture and gland formation with a significant amount of mucus. Which of the following is the most significant risk factor for this patient’s most likely diagnosis?

A) Medications

B) Occupational history

C) Past medical history

D) Race

E) Sex

A 47-year-old woman presents to her physician for difficulty swallowing. She states that she intentionally delayed seeing a physician for this issue. She says her primary issue with swallowing is that her mouth always feels dry so she has difficulty chewing food to the point that it can be swallowed. On physical examination, her oral mucosa appears dry. Both of her eyes also appear dry. Several enlarged lymph nodes are palpated. Which of the following patterns of reactive lymphadenitis is most commonly associated with this patient’s presentation?

A) Sinus hyperplasia

B) Follicular hyperplasia

C) Paracortical hyperplasia

D) Diffuse hyperplasia

E) Mixed B and T cell hyperplasia

 

Embryology

A 2-year-old boy is brhhhjought to the emergency department by his mother for evaluation of severe abdominal pain that began 1 hour ago. On examination, the patient is afebrile and has diffuse rebound tenderness with acute epigastric pain. A stool guaiac test is positive. A small bowel perforation is suspected. What is the embryologic structure that is the underlying cause of this patient’s presentation?

A) Vermiform appendix

B) Anal membrane

C) Fibrous cord remnant

D) Vitelline duct

E) Cloaca

A 22-year-old woman presents to the gynecologist for evaluation of amenorrhea and dyspareunia. The patient states that she recently got married and has been worried about getting pregnant. The patient states that she has never had a period and that sex has always been painful. On examination, the patient is Tanner stage 5 with no obvious developmental abnormalities. The vaginal exam is limited with no identified vaginal canal. What is the most likely cause of this patient’s symptoms?

A) Hyperprolactinemia

B) Exposure to DES in utero

C) Turner syndrome

D) PCOS

E) Mullerian aganesis