Catheter-related Staphylococcus aureus infections.

Among 3394 patients with Staphylococcus aureus bacteraemia from the years 1986-89, 88 patients were found whose intravenous catheter and blood grew organisms of the same phage type. Strains of phage type 95 were more frequent among the patients with confirmed catheter-related bacteraemia than among other bacteraemia cases. Strains with particular phage-type patterns occurring with increasing frequency in Denmark during recent years also occurred with significantly higher frequencies among the confirmed catheter-related bacteraemias. No major differences in antibiotic resistance were observed. Patients with catheter-related bacteraemia had, in spite of a higher frequency of underlying diseases, a lower mortality compared with other bacteraemia patients, and endocarditis occurred less frequently (2% vs. 6%). Among 201 S. aureus isolates from catheters in 1988 only strains of group I occurred with increased frequency. The possible role of catheters as selection pressure on the S. aureus population is discussed.