Clinical and genetic analysis of Staphylococcus aureus nasal colonisation and exit-site infection in patients undergoing peritoneal dialysis

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