No changes in the distribution of organisms responsible for septic arthritis over a 20 year period

To assess changes in the distribution and resistance of the pathogens responsible for septic arthritis over a 20 year period in patients admitted to the same hospital unit.

Retrospective study of the hospital records of patients admitted between 1979 and 1998 for septic arthritis with positive microbiological diagnosis after blood or joint cultures, or both.

303 cases of septic arthritis were studied, 141 in the period 1979-88 and 162 in the period 1989-98. The incidence between the first and second period did not vary significantly for the staphylococci (67% v. 63%), streptococci (16% v. 20%), and Gram negative bacilli (7% v. 10%). Tuberculous infections decreased from 9% to 4% (p<0.04). No gonococci were isolated in the second 10 year period. Among the staphylococcal species, there was an increase in the number of coagulase negative staphylococci (10 cases v. 21, p<0.05) between the two periods. There was no significant difference in the frequency of occurrence of methicillin resistant pathogens (12.6% v. 16.6%). The number of streptococcal B infections increased (2 v. 10 cases), and beta-lactamine resistant pneumococci emerged. In the second 10 year period, patients were older and were more likely to have co-existing disease, particularly tumoral growth, and less commonly were receiving dialysis. Localisation of joint infection was comparable except for an increase in prosthetic knee infections.

The distribution and sensitivity of pathogens causing septic arthritis changed little over a 20 year period.