CONTROL OF AN OUTBREAK OF A HIGHLY BETA-LACTAM-RESISTANT ENTEROBACTER-CLOACAE STRAIN IN A NEONATAL SPECIAL CARE UNIT

Two successive outbreaks of colonization and infection with Enterobact er cloacae resistant to third generation cephalosporins (cephalosporin -resistant E. cloacae, CREC) and involving 15 infants occurred within 12 months in a neonatal special care unit. Isolates of clinical signif icance were obtained from four infants (urine 2 cases, blood, pleural drainage). According to epidemiological typing using computerized bioc hemical fingerprinting and pulsed-field gel electrophoresis (PFGE) the same CREC strain was found in both outbreaks. The origin of the strai n and its reservoir between the two outbreaks remained unknown. Emphas izing strict barrier nursing of the infants had little or no impact on the presence and transmission of the strain in the unit. In contrast, replacing ampicillin plus cefotaxime as standard empiric therapy with penicillin G plus netilmicin plus consequent cohorting of newborns an d staff promptly halted both the outbreaks. During a 5-y follow-up aft er the last episode, the choice of antibiotics for empirical treatment has varied, and no further outbreaks of CREC have been seen, with the exception of two sporadic cases.