Outbreak of infections due to P-fimbriated Escherichia coli O16:K1 in a neonatal intensive care unit.

In recent years neonatal Escherichiu coli septicemia has been rare in the neonatal intensive care unit (NICU) at the Karolinska Hospital, with only one case diagnosed in 1981-1985 (1). During December 1986, however, an outbreak of severe nosocomial E. coli infections occurred in the NICU. One case each of meningitis, septicemia and pneumonia were diagnosed within a three week period. The three infants were simultaneously nursed in the same room during a period of overcrowding. All three infections were caused by E. coli with identical multiple antibiotic resistance patterns (resistant to ampicillin, piperacillin, cephalotin, trimethoprim-sulphamethoxazole, doxycycline). The isolates from blood and cerebrospinal fluid (CSF) were P-fimbriated and of identical biotype and serotype (016 : K1) whereas the isolate from tracheal secretions was not available for further typing.