Clinical Orthopaedics and Related Research®

, Volume 468, Issue 8, pp 2107–2112

Microbiology of Bone and Joint Infections in Injecting Drug Abusers

  • Daniel C. Allison
  • Paul D. Holtom
  • Michael J. Patzakis
  • Charalampos G. Zalavras
Symposium: Papers Presented at the 2009 Meeting of the Musculoskeletal Infection Society

DOI: 10.1007/s11999-010-1271-2

Cite this article as:
Allison, D.C., Holtom, P.D., Patzakis, M.J. et al. Clin Orthop Relat Res (2010) 468: 2107. doi:10.1007/s11999-010-1271-2

Abstract

Background

The literature contains variable reports on the causative organisms of osteomyelitis and septic arthritis in patients with injecting drug abuse and on the rate of oxacillin-resistant S aureus. It is important to have a clear notion of the organisms to initiate empiric antimicrobial therapy.

Questions/purposes

We therefore determined the spectrum of organisms in bone and joint infections in patients who were injecting drug users.

Methods

We retrospectively reviewed the medical records of 215 patients (154 male, 61 female) with a history of injecting drug abuse and concurrent bone and/or joint infection from 1998 to 2005. The mean age was 43 years (range, 23–83 years). Osteomyelitis was present in 127 of the 215 patients (59%), septic arthritis in 53 (25%), and both in 35 (16%). The lower extremity was most commonly involved (141 cases, 66%), with osteomyelitis of the tibia present in 70 patients (33%) and septic knee arthritis in 30 patients (14%).

Results

Cultures yielded predominately Gram-positive bacteria: Staphylococcus aureus in 52% and coagulase-negative Staphylococcus in 20%. The proportion of oxacillin-resistant S aureus among S aureus infections increased from 21% in 1998 to 73% in 2005. Gram-negative organisms were present in 19% of infections and anaerobes in 13%. Patients with osteomyelitis had a higher prevalence of polymicrobial infections (46% versus 15%), infections due to Gram-negative organisms (24% versus 9%), and anaerobic infections (19% versus 6%) compared to patients with septic arthritis.

Conclusions

These findings suggest broad-spectrum empiric antibiotic therapy, including vancomycin, should be considered for bone and joint infections in patients with injecting drug abuse.

Level of Evidence

Level IV, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Copyright information

© The Association of Bone and Joint Surgeons® 2010

Authors and Affiliations

  • Daniel C. Allison
    • 1
  • Paul D. Holtom
    • 1
  • Michael J. Patzakis
    • 1
  • Charalampos G. Zalavras
    • 1
  1. 1.Department of Orthopaedic Surgery, Keck School of MedicineUniversity of Southern CaliforniaLos AngelesUSA