Rheumatic Fever

Acute rheumatic fever is an autoimmune inflammatory reaction that follows a Group A Streptococcus (GAS) infection, usually involving the pharynx and, in some settings, the skin. The organism is no longer simply “sitting in the heart.” Instead, immune responses directed against GAS cross-react with human tissues through molecular mimicry. Inflammation may involve the heart, joints, skin, and central nervous system. The cardiac inflammation is the complication with the greatest long-term consequence. It can affect the valves, myocardium, and pericardium. Valve inflammation may produce regurgitation, a new murmur, reduced cardiac output, and eventually chronic rheumatic heart disease. Conduction-system inflammation may prolong the PR interval or contribute to dysrhythmias. Carditis can be clinically silent, so a patient who denies chest pain may still need echocardiographic assessment. Joint inflammation typically causes fever and painful, swollen joints, often with a migratory pattern. Sydenham chorea reflects central nervous system involvement and may appear as purposeless, irregular movements, clumsiness, emotional lability, or deterioration in handwriting. Erythema marginatum and subcutaneous nodules are less common but are highly specific findings when present. Acute rheumatic fever is not the...