Sinoatrial block complicating legionnaire's disease.

A 59 year old woman presented with acute onset of fever, chills, diaphoresis, vague chest discomfort, and was found to be hypotensive and tachypnoeic. An electrocardiogram demonstrated sinoatrial block with a junctional rhythm between 50 and 80 beats/min. All cultures were negative and imaging studies unrevealing. Her urine tested positive for Legionella pneumophila antigen serotype 1 and she improved with antibiotic therapy.