Peptoniphilus asaccharolyticus - Commensal, pathogen or synergist? Two case reports on invasive Peptoniphilus asaccharolyticus infection.

Peptoniphilus asaccharolyticus are gram-positive anaerobic cocci (GPAC) usually found as commensals of the skin or in the setting of polymicrobial colonisation of chronic wounds and ulcers. However, its pathogenic potential in more severe, invasive infections such as bone, joint or blood stream infections remains unclear, with studies on underlying virulence factors still pending. In this case report we present two cases of P. asaccharolyticus-associated infections of the bone and joint as well as a review of the literature. The cases cast a new light on possible synergistic interactions between P. asaccharolyticus and more virulent aerobic bacteria as well as on its role as pathogen in severe mono-infection.