Propionibacterium acnes as an etiological agent of arthroplastic and osteosynthetic infections--two cases with specific clinical presentation including formation of draining fistulae.

This report describes two patients with orthopaedic implant infections, with specific clinical presentations including formation of draining fistulae. Propionibacterium acnes was isolated in multiple cultures in both cases. Phenotypic and genetic characterisation of the isolates clearly emphasizes the significance of P. acnes as an etiological agent of implant infections. These infections are insidious with delayed presentation of symptoms and may have been overlooked because of the consideration of P. acnes as a contaminating commensal as well as the frequent use of suboptimal culture procedures.