Risk factors associated with extended spectrum beta lactamase Klebsiella pneumoniae outbreak in a neonatal intensive care unit.

Abstract

Objective: (1) identify risk factors for extended-spectrum beta-lactamase Klebsiella pneumoniae (ESBL-KP) acquisition in the neonatal intensive care unit (NICU) and (2) evaluate the clinical impact of ESBL-KP acquisition on neonatal outcomes at NICU discharge.

Design: This retrospective case-control study (Aug 2022-Sept 2025) compared neonates who acquired ESBL-KP in the NICU (cases) with those who did not (controls).

Patients: 600 neonates admitted to a Kuwaiti NICU located in a general hospital.

Methods: Data included clinical, demographic, antibiotic, and laboratory records. The primary outcome was ESBL-KP acquisition. The secondary outcome was status at NICU discharge. Regression analysis was used to evaluate associations for the primary and secondary outcomes.

Results: Of 600 neonates, 30% acquired ESBL-KP. Among these, 12% had bloodstream infections (BSIs). Length of NICU stay (OR:1.02, 95% CI:1.01-1.03), intrauterine growth restriction (IUGR) (OR:2.59, 95% CI:1.08-6.24), extreme-prematurity (OR:2.89, 95% CI:1.29-6.47), previous hospital admission (OR:4.45, 95% CI:1.75-11.32), and prior ampicillin use (OR:3.51, 95% CI:2.12-5.82) were statistically significant risk factors for acquisition of ESBL-KP in the adjusted regression model. Moreover, ESBL-KP-positive neonates faced 12.83 times greater odds of death from sepsis (95 % CI: 2.41-68.22), than ESBL-KP negative neonates.

Conclusions: ESBL-KP acquisition was strongly linked to IUGR, extreme prematurity, previous admission, and ampicillin use. While a longer hospital stay correlated with acquisition, this relationship is prone to time-dependent bias and reverse causation. Acquisition also raised sepsis-related mortality risk, though small sample sizes require cautious interpretation. Targeted prevention is essential to improve neonatal outcomes.