PURPOSE OF THE STUDY: Annually, more than a million joint replacements are performed worldwide. The most feared complication is
infection. The purpose of this study is to establish the spectrum of organisms and their respective sensitivities, cultured during primary and secondary debridements of staged revision surgery. These findings were then utilised to suggest alternative empiric antimicrobial therapy.
DESCRIPTION OF METHODS: A retrospective analysis was performed on patients undergoing revision hip or knee arthroplasty at a tertiary hospital in South Africa from June 2005 to March 2009. Only patients in whom intra-operative deep microbiological
cultures had been performed were included.
SUMMARY OF RESULTS: Deep microbiological cultures were performed in all cases on either joint synovium, fluid or pus swabs taken from the site intra-operatively. Following primary debridement of staged revision surgery, 38% of samples submitted
were culture positive from 61 patients, rendering 29 isolates (six double infections). The spectrum was highly variable. Although no methicillin-resistant Staphylococcus aureus (MRSA) was isolated in the initial cultures, the majority of organisms were Gram positive (62%).