Microbiology of Bone and Joint Infections in Injecting Drug Abusers

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 coagulasenegative 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.

pH-controlled delivery of gentamicin sulfate from orthopedic devices preventing nosocomial infections

“…In the presence of infection, the local pH decreases leading to the antibiotic release. Using this smart biomaterial, the drug will be released once the infection occurs (immediately after the implantation or months, years later) which limits systemic toxicity, antibiotic resistance and decreasing bioavailability [23,24]. For our study, we have chosen gentamicin sulfate (GS) as antibiotic.…”

Osteomyelitis: An Update for Hospitalists

“…In 1 case series, 73% of intravenous drug users with vertebral osteomyelitis had MRSA. 31 The outcomes in these small case series are about the same (ie, relapse rates , 15%), with a treatment duration of 60 days. 27,33 Vancomycin monotherapy may prove to be an insufficient treatment for vertebral osteomyelitis.…”

“…30 The aging population, the increasing use of immunemodulating agents, and intravenous drug use all affect the epidemiology of the disease. 31 Case series of osteomyelitis from the 1990s confirmed S aureus as the most likely organism causing hematogenous spread in adults, and that there is a shift toward more frequent infection in vertebrae than in other bones. 32 Relapse rates in those series were , 15%.…”

The burden of bone, native joint and soft tissue infections on orthopaedic emergency referrals in a city hospital

“…More recently, Allison et al reported on the microbiology of orthopaedic related infections secondary to drug abuse. 23 They reviewed 215 patients over 7 years, and found a high incidence of osteomyelitis (59%) and a predominance of Gram positive bacteria. Wang et al compared the demographics, presentation, treatment and outcomes of surgically treated primary pyogenic infections of the spine between IVDU and non-IVDU patients.…”