Clinical and genetic analysis of Staphylococcus aureus nasal colonisation and exit-site infection in patients...

Few data exist regarding the clonal identity of Staphylococcus aureus (SA) that colonises the nostrils and causes exit-site infections in peritoneal dialysis patients. Nasal and exit-site swabs were taken monthly from 41 patients undergoing peritoneal dialysis, and a genetic analysis of SA isolates was performed by pulsed-field-gel electrophoresis. When SA was identified at the exit-site, the clonal identity of nasal and exit-site isolates was demonstrated. In 50% of the SA carriers, nasal isolates were genetically constant over time; in the other 50% a change of colonising SA strains was observed. The risk of exit-site infection was identical in both groups.