A 10-year-old child presents with low-grade fever, malaise, and a new apical diastolic rumble with an opening snap 3 weeks after an untreated skin infection with group A streptococcus. Blood cultures are negative. Echocardiography shows a small vegetation on the anterior mitral leaflet. Which of the following is the most likely diagnosis?

• A Acute rheumatic carditis ✓
• B Libman-Sacks endocarditis
• C Infective endocarditis with culture-negative organism
• D Nonbacterial thrombotic endocarditis

Explanation

A new diastolic rumble with opening snap at the apex indicates mitral stenosis, which is the hallmark chronic sequela of rheumatic carditis and can rarely present acutely. The history of streptococcal skin infection supports this. Acute rheumatic carditis primarily affects the mitral valve and produces regurgitation, but a Carey Coombs diastolic murmur (from valvulitis without commissural fusion) can be heard acutely. Infective endocarditis with negative blood cultures is unlikely to produce a diastolic rumble with opening snap, which indicates established mitral valve pathology.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.