Staphylococcus aureus as source of catheter-related bloodstream infection evaluated by PFGE and rep-PCR typing in a Brazilian hospital
Staphylococci are a common cause of catheter-related bloodstream infection (CR-BSI), and epidemiological typing is an important tool for effective infection control. This study evaluated by PFGE and rep-PCR whether Staphylococcus aureus strains isolated from skin and catheter tips were related to specimens isolated from blood. A prospective observational study, carried out in a clinical surgical ward at a Brazilian hospital between September 2000 and November 2002, investigated non-tunneled central venous catheters from 179 patients. S. aureus isolates were mainly obtained from blood (41.4%), while coagulase-negative staphylococci strains were more often isolated from the skin at the catheter insertion site (49.7%) and from the catheter tip (57.5%). Among the 21 strains isolated from 9 patients at 2 or 3 sites simultaneously, 9 were methicillin-resistant S. aureus (MRSA) and 12 were methicillin-susceptible S. aureus (MSSA). Seven patients harbored the same S. aureus strain isolated from the skin, blood and/or catheter tip cultures. MRSA isolates belonged to one PFGE pattern (type A- subtypes A1, A2 and A3), and to two rep-PCR patterns (a and b). MSSA isolates were distinguished in five PFGE (B to F) and in three rep-PCR (c, d and e) patterns. Both PFGE and rep-PCR methods indicated that the skin at the catheter insertion site was the origin of CR-BSI caused by S. aureus.
Document Type: Original Article
Affiliations: 1: Laboratório de Microbiologia, Área de Imunologia, Microbiologia e Parasitologia, Universidade Federal de Uberlândia, Minas Gerais 2: Laboratório de Infecções Hospitalares, Departamento de Microbiologia Médica, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
Publication date: 2008-11-01