Physician Assistant Clinical Knowledge 3

Question 1

A 28-year-old female presents with malar rash, arthritis, and proteinuria. ANA is positive at 1:640. Which antibody is most specific for systemic lupus erythematosus (SLE)?

Accepted Answer

Anti-Smith (Sm)

Answer

Anti-Smith (anti-Sm) antibodies are highly specific for SLE, though not sensitive, making them useful when positive.

Question 2

A 50-year-old man presents with dysphagia to solids and liquids simultaneously from onset. Barium swallow shows a 'bird-beak' appearance. What is the most likely diagnosis?

Accepted Answer

Achalasia

Answer

Achalasia presents with dysphagia to both solids and liquids from the start due to failure of LES relaxation, and the bird-beak appearance is classic on barium swallow.

Question 3

A neonate presents at 24 hours of life with bilious vomiting. Abdominal X-ray shows a 'double bubble' sign. What is the most likely diagnosis?

Accepted Answer

Duodenal atresia

Answer

The double bubble sign on X-ray (air in stomach and proximal duodenum) is pathognomonic for duodenal atresia.

Question 4

A 65-year-old smoker presents with hemoptysis, weight loss, and a central lung mass. Serum sodium is 120 mEq/L. Which paraneoplastic syndrome is most likely?

Accepted Answer

SIADH from ADH secretion

Answer

Small cell lung cancer most commonly produces SIADH via ectopic ADH secretion, causing hyponatremia.

Question 5

A 30-year-old woman at 32 weeks gestation presents with BP 160/110, 3+ proteinuria, and headache. Labs show platelets 85,000/µL, AST 180 U/L, and hemolytic anemia. What is the diagnosis?

Accepted Answer

HELLP syndrome

Answer

HELLP syndrome is defined by Hemolysis, Elevated Liver enzymes, and Low Platelets, and is a severe complication of preeclampsia.

Physician Assistant Practice Test

Physician Assistant Practice Test

Physician Assistant Clinical Knowledge 3