Two cases of discitis due to Propionibacterium acnes.

We report two cases of discitis due to Propionibacterium acnes and review previously published cases of bone and joint infections in which this organism was recovered as a pure culture. P. acnes is an anaerobic organism usually considered a normal inhabitant of the skin but capable of producing a variety of infections including discitis, osteitis, arthritis, and chest wall osteitis. Most patients were immunocompetent. A few infections occurred spontaneously, whereas others were secondary to a break in the skin or to implantation of foreign material into the body for instance during internal fixation of a fracture or arthroplasty. Cases of P. acnes chest wall infection have been reported in patients with palmoplantar pustulosis or chronic or multifocal osteitis, supporting a role for P. acnes in SAPHO syndrome.