Native Valve Legionella Endocarditis in a 74-Year-Old Male: A Case Report and Review

Legionella is a bacterium that primarily causes respiratory infections. Rarely, it can result in extrapulmonary infections like endocarditis. We present a case of native valve endocarditis caused by Legionella in a 74-year-old male. Our patient initially presented with fever, fatigue, confusion, moderate cough, and dysuria. Subsequent presentation included atrial fibrillation and pulmonary infiltrates on chest X-ray. His clinical sequelae and positive urine Legionella antigen prompted treatment with antibiotics and cardiac medication. Echocardiograms revealed vegetation on the mitral valve leaflet suggestive of endocarditis. The patient improved after appropriate antibiotic and anti-arrhythmic therapy. In presenting this case and literature review, we emphasize the importance of considering atypical pathogens in common clinical presentations.