Septic arthritis: a second decade of experience

To review the diagnostic features, treatment and outcomes of all cases of septic arthritis presenting to a major Australian rheumatology unit, between 1982 and 1991. These were compared with the previous decade's experience.

The medical records of all cases of septic arthritis presenting to the Combined Centre for Rheumatic Diseases, The Rachel Forster Hospital between 1982 and 1991 were reviewed and compared with the experience of the previous decade (1971-1981).

Twenty-seven episodes of septic arthritis were diagnosed in 27 patients. There were 18 females and nine males. The average age was 62 (21-83) with three patients less than 30. Their rheumatological diagnoses were: rheumatoid arthritis (RA) in 15, osteoarthritis in five, gout in two, and one each of mixed connective disease, sarcoid, tenosynovitis of the forearm, seronegative spondyloarthropathy, and non specific polyarthritis. Eleven patients were on oral corticosteroids. Four patients had intra-articular injections within two months of the onset of the septic episode. Sixteen out of 19 aspirates on the wards were positive. The organisms identified were Staphylococcus aureus in ten (one multiply resistant S. aureus (MRSA), Streptococcus four, Mycobacterium three (one atypical), two Pseudomonas and one each of Citrobacter, Enterobacter, Gram negative bacillus. Five patients did not have a causative organism identified. The site of involvement and the causative organisms were similar in both decades. All patients received intravenous antibiotics for at least two weeks and oral antibiotics for at least another four weeks. Twenty-two per cent had regular aspirations on the wards and 26% had surgical drainage performed. Only 59% of all joints returned to good function. Fifty per cent of infected arthroplasties required arthrodesis and only a third of these returned to acceptable function.

Septic arthritis in subjects with previous rheumatic disease continues to have a poor prognosis, especially in cases of infected arthroplasties. There has been no change in the types of causative organisms or sites of involvement over the last two decades.