Extended-spectrum beta-lactamases Klebsiella pneumoniae: multimodal infection control program in intensive care units

The aims of our study were to investigate a nosocomial spread of an extended-spectrum fl-lactamases-Klebsiella pneumoniae cluster at a University teaching hospital in Italy, to describe, and to monitor the implementation of a multimodal infection control program in two mixed ICUs.

During the 1 October 2005-30 September 2006 period, 79 colonized patients have been identified. Isolates were genotyped by pulsed-field gel electrophoresis (PFGE). A mutimodal infection control program with monitoring of alcohol-based hand rub was performed in Intensive Care Units (ICU A and ICU B).

The epidemiological investigation and PFGE showed a horizontal transmission of the same PFGE genotype, with the isolation of the outbreak strain on the hand of one healthcare operator. Alcohol based hand rub was adopted in ICUA on 18 March 2006, in addition to hand washing with plain or antiseptic soap. ICU B did not change its hand hygiene habits. Following the implementation of the program, the incidence density rate (IDR) in ICU A fell down from 4.50 to 1.68/1000 patient days.

Our findings confirm the important role of personnel in cross-transmission. Moreover the inbuilt control group involuntarily offered by the delaying of the intervention in ICU B has given the opportunity to verify the epidemiological association between the actual implementation of infection control practices and the outbreak control.