Abstract

Legionella disease is a systemic infection with rare cardiac manifestations. Known cardiac presentations include myocarditis, pericarditis, endocarditis and pericardial effusion. Only two cases of conduction disturbance have been reported in adults, one in the setting of verapamil use. A 56 year-old African American woman with a history of active tobacco abuse and diabetes presented with fevers, fatigue and altered mental status and was subsequently found to have community acquired pneumonia (CAP). Initial electrocardiogram (EKG) showed 2:1 atrioventricular (AV) block in the absence of baseline conduction system disease or electrolyte abnormalities. The patient had a positive urinary Legionella antigen and was started on intravenous levofloxacin. The patient’s hospital course was complicated by hypoxemic respiratory failure requiring intubation, acute renal failure, hyponatremia, elevated liver associated enzymes and progression to third degree AV block, requiring both transcutaneous and transvenous pacing. Legionella should be considered for patients who present with new onset cardiac conduction disturbance in the setting of community acquired pneumonia. Early detection and prompt treatment with intravenous antibiotics is crucial to ensure full recovery from this form of reversible, infectious heart block.

Key words: Legionella, heart block, pneumonia, respiratory failure.