Background: Between June and October 1997, and during April 1998, a cluster of nosocomial bloodstream infections (BSIs) associated with Klebsiella pneumoniae was observed in 8 premature neonates from 1 pediatric intensive care unit (TPICU) in a 4000-bed medical center in northern Taiwan. An investigation was conducted to identify the possible reservoirs and mode of transmission.
Methods: Epidemiologic surveillance and infection control interventions were executed. The environment was checked by submitting several swab samples for microbiological studies. The antibiograms and results from 2 molecular typing methods (pulsed-field gel electrophoresis and infrequent-restriction site polymerase chain reaction) of all bacteremic and environmental isolates of K. pneumoniae were compared.
Results: Totally 39 K. pneumoniae isolates, including 9 from bacteremia, 26 from the environment, and 4 controls, were analyzed. One major pattern was found in 21 isolates, which included 8 bacteremic isolates with identical antibiograms, a single isolate from rectal swab screening, 2 of 8 isolates from hand cultures of medical staff, and 10 of 17 isolates from swabs of sinks in the TPICU. All 21 isolates illustrated identical antibiograms, while the other 18 isolates shared 4 antibiograms and 15 unique patterns.
Conclusions: The nosocomial BSIs appeared to be an outbreak induced by 1 multiresistant K. pneumoniae strain. The sinks may have acted as reservoirs for this outbreak strain. During washing, splattered water droplets containing the bacterial particles may have contaminated the hands of medical personnel and were then further transmitted to patients.