[Outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a neonatal intensive care unit: Risk factors and key preventive measures for eradication in record time].

Introduction: In November 2014, an extended-spectrum beta-lactamase producing Klebsiella pneumoniae outbreak was detected in the neonatal intensive care unit of a tertiary care hospital.

Objective: Our aim was to determine the clinical, epidemiological and microbiological characteristics of the outbreak, to analyse the identified risk factors and to describe the preventive and control measures implemented for its eradication.

Methods: We conducted a case-control study. We performed Univariate and bivariate analyses, defining statistical significance as a p-value of less than 0.05. The implemented preventive and control measures were aimed at establishing the magnitude of the outbreak, effective communication, the evaluation of health care processes and education on patient safety. Clinical samples were collected for molecular and phenotypic characterization.

Findings: The sample consisted of 51 newborns, of who 17 were cases and the remaining 34 controls. The distribution of cases by birth weight was: 2 cases (11.8%) greater than 2500g, 4 cases (23.5%) between 1500 and 2500g, 5 cases (29.4%) between 1000 and 1500g, and 5 cases (29.4%) less than 1000g. In one case, the birth weight was not documented in the health record. The following risk factors for colonization or infection were statistically significant in our study: presence of a central venous catheter (OR, 5.0 [95% CI, 1.4-17.8]; P=.016); parenteral nutrition (OR, 6.8 [95% CI, 1.8-25.7]; P=.006); urinary catheterization (OR, 5.9 [95% CI, 1.2-30.0]; P=.028) and birth weight (P=.035). We found statistically significant differences in the mean total length of stay in hospital (P=.004) and length of stay in the NICU (P=.002). All 17 cases presented antimicrobial resistance with presence of extended-spectrum beta-lactamase type CTX-M-14.

Conclusion: Workplace interventions focused on patient safety need to be reinforced, especially those concerning practices with the potential to increase the extrinsic risk of colonization or infection by extended-spectrum beta-lactamase -producing K. pneumoniae in the NICU, such as the insertion, care and maintenance of central venous catheter, parenteral nutrition and urinary catheterization.