Colonisation by extended-spectrum β-lactamase-producing Klebsiella spp. in a paediatric intensive care unit

A prospective cohort study was performed in order to study the incidence and risk factors for bacterial colonisation with extended-spectrum producing β-lactamase (ESBL) Klebsiella spp. in children. The study took place in a paediatric intensive care unit (PICU) in Recife, Brazil over a five-month period in 2008. Rectal swabs were collected during the first 24 h of admission and on the 2nd, 5th, 7th and 14th days of PICU stay. ESBL-producing strains of Klebsiella spp. were detected by Kirby-Bauer disc diffusion and confirmed by double disc synergy testing. A total of 186 children were enrolled with a median age of three years. The overall colonisation rate with ESBL-producing Klebsiella spp. was 14%, but 13 (7%) children were already colonised upon admission. The incidence density of colonisation during PICU admission was 14.2 per 1000 patient-days. On multivariable analysis, the use of third generation cephalosporins (P = 0.008) was a risk factor for colonisation. Survival analysis revealed an increase in the accumulated risk of colonisation with an increase in length of stay in the PICU. The present study provides baseline information to guide improved practices in similar settings and direct future studies in relation to the magnitude of cross-infection and effectiveness of infection control interventions.