Nosocomial colonization of premature babies with Klebsiella oxytoca: probable role of enteral feeding procedure in transmission and control of the outbreak with the use of gloves.

OBJECTIVE: To investigate the persistence of colonization of premature babies by Klebsiella oxytoca, with special emphasis on the mode of transmission of the bacterium and evaluation of Standard Precautions to stop the epidemic.
DESIGN: Retrospective analysis of cases and prospective study of systematic bacteriological samples (stools and throat) from babies, healthcare workers (HCWs), and environment, with genotyping of strains by arbitrarily primed polymerase chain reaction.
SETTING: A premature baby unit (PBU) and a neonatal intensive care unit in the university hospital of Saint-Etienne, France.
RESULTS: An outbreak of K oxytoca was suspected in two pediatric wards after the occurrence of a fatal bacteremia in a newborn hospitalized in the PBU and the colonization of other babies 2 months later. Retrospective analysis showed that 24 babies' digestive tract had been colonized. No environmental reservoir was recovered in the units nor in enteral feeding. No K oxytoca was isolated from HCW samples. Genotyping confirmed the presence of epidemic strains, although independent clones were responsible for infections or colonizations in each of the two units. The chronology and the site of babies' colonization (isolation of K oxytoca in stools before throat) were determined during a prospective study and suggested that enteral feeding procedures could be the source of contamination. Therefore, use of gloves during this practice by HCWs was recommended and, after readjustment of Standard Precautions, stopped the outbreak.
CONCLUSION: To prevent cross-contamination among high-risk babies, careful attention must be paid to Standard Precautions. Bacteriological surveillance of the digestive tract of neonates could help to check compliance with these guidelines