title: Arthritis due to Mycobacterium xenopi: a retrospective study of 7 cases in France.
abstract: BACKGROUND
  Mycobacterium xenopi is a nontuberculous mycobacterium responsible for opportunistic and nosocomial infections, chiefly of the lung; few cases of bone and joint infection have been reported. From July 1989 through May 1993, an outbreak of 58 cases of nosocomial discitis due to M. xenopi infection following percutaneous nucleotomy occurred in a French hospital. Peripheral M. xenopi arthritis seems exceedingly rare. We conducted a study to assess the epidemiological and clinical patterns of M. xenopi arthritis.
  
  
  METHODS
  We retrospectively reviewed cases of M. xenopi arthritis reported from May 1993 through October 2004.
  
  
  RESULTS
  We identified 7 cases, all of which occurred after invasive surgical procedures were performed on the affected joint, suggesting a nosocomial pattern of infection. Two patients may have been contaminated at the hospital where the M. xenopi discitis outbreak occurred. No source was identified in the other 5 patients. Despite the probable nosocomial nature of the infections, the diagnosis was delayed (mean time until diagnosis, 50 months). Repeated collection of deep tissue specimens for bacteriological analysis seemed crucial to the diagnosis. The treatment relied on combination antimicrobial therapy and surgery. Among 11 cases of M. xenopi osteoarticular infection reported in the literature from 1975 to 2005, (arthritis in 9 cases and osteitis in 2), none were nosocomial.
  
  
  CONCLUSIONS
  A high index of suspicion should be maintained to ensure the diagnosis of M. xenopi arthritis before chronic monoarthritis and before the development of irreversible joint damage.
authors.affiliation: Department of Internal Medicine and Rheumatology, Diaconesses-Croix-Saint-Simon Hospital, Paris, 75020, France. carinesalliot@wanadoo.fr
authors.forename: Carine
authors.initials: C
authors.lastname: Salliot
authors.forename: Nicole
authors.initials: N
authors.lastname: Desplaces
authors.forename: Philippe
authors.initials: P
authors.lastname: Boisrenoult
authors.forename: Anne Claude
authors.initials: AC
authors.lastname: Koeger
authors.forename: Philippe
authors.initials: P
authors.lastname: Beaufils
authors.forename: Véronique
authors.initials: V
authors.lastname: Vincent
authors.forename: Patrick
authors.initials: P
authors.lastname: Mamoudy
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Ziza
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000382:microbiology; D001170:Arthritis, Infectious / Q000382:microbiology*; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects; D001182:Arthroscopy / Q000009:adverse effects*; D003428:Cross Infection / Q000382:microbiology*; D017587:Diskectomy, Percutaneous / Q000009:adverse effects*; D005260:Female; D005602:France; D006801:Humans; D007719:Knee Joint / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000382:microbiology* / Q000628:therapy; D019912:Mycobacterium xenopi; D012189:Retrospective Studies; D012307:Risk Factors