The outcome of bacterial arthritis: a prospective community-based study.

Objective: To assess the outcome and adverse prognostic factors of bacterial arthritis (BA).

Methods: In a prospective community survey of BA, data were collected at the time of diagnosis and at a mean of 2 years later. A poor patient outcome was defined as death due to BA or severe overall functional deterioration. A poor joint outcome was defined as amputation, arthrodesis, prosthetic surgery, or severe functional deterioration. Possible prognostic factors were analyzed by univariate analysis.

Results: BA was diagnosed in 154 patients, 121 adults and 33 children. One-half of the adults had a preexisting joint disease and 29% of the infected joints contained synthetic material. The patient outcome was poor in 21% of all patients, and the joint outcome was poor in 33% of the surviving patients. Adverse prognostic factors were an older age, preexisting joint disease, and an infected joint containing synthetic material. These factors were interrelated. There was no association between a poor outcome and young age, comorbidity, immunosuppressive medication, functional class, multiple infected joints, type of microorganism, or treatment delay.

Conclusion: BA had a poor outcome in almost one-half of the patients. Patients who were older, had a preexisting joint disease, and/or had an infected joint containing synthetic material had the poorest prognosis.