Pyogenic arthritis of native joints in non-intravenous drug users: A detailed analysis of 268 cases attended in a tertiary hospital over a 22-year period.

OBJECTIVE

To analyze the clinical features, microbiological spectrum, diagnostic procedures and outcomes in native joint pyogenic arthritis among non-intravenous drug users.

METHODS

We collected all microbiologically proved cases of infectious arthritis at our hospital between 1992 and 2013. Patients with prosthetic joint infection were excluded, as were patients with non-pyogenic arthritis and intravenous drug users.

RESULTS

We identified 268 patients; the mean age was 61 ± 14.7 years and 62% were men. The incidence increased over the period of study. In 188 patients (70%), one or more underlying medical illnesses were found. The mean symptom duration was 8.9 ± 9.5 days. Globally, 311 affected joints were found, 232 (75%) involving peripheral joints and 79 (25%) axial joints. Staphylococci (55%) and Streptococci (29%) were the predominant microorganisms. Blood cultures were positive in 78% (173/223) of the cases. In 81 patients (30%), one or more concomitant infectious processes were found. Antimicrobial therapy was prescribed 4-8 weeks in most cases, and surgical drainage was performed in 65% of patients. Four patients relapsed and 23 (8%) died.

CONCLUSIONS

The prevalence of pyogenic native joint arthritis in non-intravenous drug users is increasing, frequently affecting old patients with underlying medical conditions. Although large joints are the most frequently compromised, the involvement of axial joints is a relevant feature that has not been recognized in other series. Staphylococci and Streptococci are the main causative agents. Bacteremia and concomitant infectious processes are frequent complications. Diagnostic delay and mortality continue to be important concerns.