Musculoskeletal infections in intravenous drug addicts: report of 34 cases with analysis of microbiological aspects and pathogenic mechanisms.

OBJECTIVE

To analyse characteristics of musculoskeletal infections in Spanish intravenous (i.v.) drug addicts.

METHODS

A retrospective analysis of 34 medical records was carried out and the aetiologic agent was confirmed in all cases.

RESULTS

The mean age was 26 years and the sex ratio was 25M/9F. Twenty-four patients were HIV-positive and 10 HIV-negative. There were no differences between the 2 subgroups. Septic arthritis, seen in 27 cases (79%), was the most common type of infection. Axial involvement was present in 23 cases (67%). The organisms isolated included Staphylococcus aureus (25 cases), Candida albicans (3 cases), Mycobacterium tuberculosis (2 cases), and Neisseria gonorrhoeae, Salmonella typhi, Staphylococcus epidermidis and Streptococcus pyogenes in one case each. Candida albicans affected the sternocostal joints. Laboratory data showed non-specific findings. The outcome was mostly good and only one patient died.

CONCLUSION

Human immunodeficiency virus does not affect characteristics of musculoskeletal infections in i.v. drug addicts. Staphylococcus aureus is the most frequently isolated pathogen in this population.