ASSESSMENT OF MULTIPLE COAGULASE-NEGATIVE STAPHYLOCOCCI ISOLATED IN BLOOD CULTURES USING PULSED-FIELD GEL-ELECTROPHORESIS

One of the criteria used to determine the clinical importance of coagu lase-negative staphylococci (CNS) is the isolation of the bacteria fro m sequential blood cultures, Sequential isolates of CNS obtained from five immunocompromised patients over three months were genetically cha racterized by pulsed-field gel electrophoresis (PFGE). This typing met hod was compared to two first-line typing methods: determination of th e species and of antibiotic susceptibility. In four patients the initi al clinical evaluation changed because of the PFGE results; several ep isodes of bacteremia would have been wrongly assessed if only the biot ype and the antibiotype had been determined. Pulsed-field gel electrop horesis should therefore be used for CNS strains from immunocompromise d patients or those suffering from chronic diseases with non-concordan t biotype and antibiotype.