Acute Rheumatic Fever

BACKGROUND: Acute rheumatic fever (ARF) is an immune-mediated sequela of group A streptococcal infection that can progress to rheumatic heart disease (RHD), defined by permanent rheumatic valvular damage. Although uncommon in the United States, delayed recognition may lead to advanced valve disease and arrhythmias. CASE SUMMARY: A 10-year-old African-American male presented after syncope following 4 months of unexplained bilateral ankle arthritis. He was found to be in atrial flutter. Echocardiography showed a flail mitral valve with severe regurgitation, moderate tricuspid regurgitation, and mild-to-moderate aortic insufficiency. After several cardioversions to re-establish sinus rhythm, he underwent mitral valve replacement and tricuspid annuloplasty 1 week after presentation. DISCUSSION: This case highlights the need for a high index of suspicion for ARF in children presenting with unexplained inflammatory symptoms and new cardiac findings, even in low-prevalence settings. Early recognition, treatment, and secondary prophylaxis help prevent recurrent ARF and progression to RHD. TAKE-HOME MESSAGE: Children with unexplained arthritis, systemic inflammation, arrhythmia, and multivalvular disease should be evaluated for ARF and evolving RHD to reduce morbidity and prevent disease progression.