Three-decade trends in the distribution of organisms causing septic arthritis in native joints: single-center study of 374 cases

Objective: A rise in the incidence of septic arthritis due to methicillin-resistant Staphylococcus aureus (MRSA) has been reported in several parts of the world. Here, our objective was to look for changes over the last 30years in the distribution and antibiotic susceptibility profiles of organisms responsible for septic arthritis.

Methods: We conducted a single-center retrospective study of all cases of septic arthritis documented by joint specimens and/or blood cultures between 1979 and 2008. Prosthetic joint infections were excluded.

Results: We enrolled 374 patients, of whom 127, 136, and 111 were included during each decade, respectively. We detected no significant time trends in the proportions of staphylococci (67%, 65%, and 64%), streptococci (14%, 21%, and 17%), or Gram-negative rods (7%, 10%, and 14%). Tuberculosis was more common during the earliest decade (1979-1988, n=10, 4, 2%; P<0.05). No significant changes occurred in the proportions of methicillin-resistant staphylococci or MRSA (13%, 11%, 15%). Age and prevalence of risk factors for infection increased over time.

Conclusion: The distribution and susceptibility of organisms causing septic arthritis has changed little over time. Our findings do not support the use of broader-spectrum antibiotics when empirical treatment is deemed necessary at our center.