Which of the following is the most common clinical feature at presentation in acute rheumatic fever (ARF)?

Correct Answer: A

Rationale: Acute rheumatic fever (ARF) is a complication of group A Streptococcus infection, diagnosed by the Jones criteria. Arthritis (Choice A) is the most common presenting feature, occurring in 60-75% of cases, typically as migratory polyarthritis affecting large joints. Carditis (Choice B) occurs in 50-60% of cases and is a major criterion, but it’s less frequent at initial presentation than arthritis. Erythema marginatum (Choice C) and subcutaneous nodules (Choice D) are rare, occurring in <5% and <1% of cases, respectively, and are not the most common presenting features. Arthritis’s high prevalence and early onset make it the correct answer.

Correct Answer: C

Rationale: Choice C is false; an emergency court order is indicated if parents refuse hospitalization in suspected abuse with safety risks (AAP). All other statements (A, B, D, E) are true per abuse protocols.

Correct Answer: C

Rationale: Length may stay normal in chronic malnutrition as stunting lags, unlike weight-for-height or weight , which drop acutely (WHO). D, E decline later.

Correct Answer: D

Rationale: Gastroenteritis causes hypovolemic hyponatremia via fluid loss and hypotonic replacement, per clinical data (AAP). A-C, E are less common.

Correct Answer: C

Rationale: Food allergies , like peanuts, are the leading cause of anaphylaxis in ED visits, per AAAAI. A, D-E are less frequent.