Pacemaker endocarditis due to Propionibacterium acnes.

Propionibacterium acnes belongs to the cutaneous flora of humans; it is often considered to be contaminant but has also been found to be a pathogen in human diseases. It is an uncommon causal agent in infective endocarditis and appears to have a predilection for prosthetic valves and foreign bodies. We describe a case of pacemaker endocarditis which shows that so-called harmless bacteria like P. acnes must be considered to be potential pathogens.