Rotavirus-Associated Myocarditis in an Immunocompetent Adult: A Case Report.

A previously healthy, 28-year-old man presented with a two-day history of diarrhea and chest pain, suggestive of infectious myocarditis. Initial workup revealed elevated troponin-I levels and diffuse ST-segment elevations on electrocardiogram (ECG). Transthoracic echocardiography showed a reduced left ventricular ejection fraction (40-45%), posteroinferior wall akinesis, and a small pericardial effusion. Stool studies were positive for rotavirus antigen via enzyme immunoassay (EIA). Cardiac magnetic resonance imaging (MRI) and endomyocardial biopsy (EMB) were not performed due to facility limitations; however, clinical findings, troponin-I trends, and echocardiographic abnormalities supported the diagnosis of rotavirus-associated myocarditis. The patient was treated with oral rehydration, colchicine, and metoprolol, leading to symptom resolution and a decline in troponin-I levels. This case underscores the importance of considering rotavirus as a potential etiologic agent in myocarditis, even in immunocompetent adults without significant comorbidities, and highlights the need for clinicians to recognize gastrointestinal viruses as possible causes of cardiac inflammation.