Efficacy of a coordinated strategy for containment of multidrug-resistant Gram-negative bacteria carriage in a Neonatal Intensive Care Unit in the context of an active surveillance program

Antimicrobial resistance in neonatal intensive care unit (NICU) patients is a threat, due to the frequent use of antimicrobial treatment and invasive devices in fragile babies. Since 2014 an active surveillance program of multidrug-resistant Gram-negative bacteria (MDR-GNB) carriage has been in place in the five NICUs of Palermo, Italy. In 2017 an increase in the prevalence of MDR-GNB, and in particular of extended-spectrum β-lactamases-producing Klebsiella pneumoniae (ESBL-KP), was observed in "Civico" hospital NICU. To assess the impact of a coordinated intervention strategy in achieving long-lasting reduction of MDR-GNB prevalence in the NICU. Rectal swabs were obtained monthly and processed to detect MDR-GNB using standard methods. MDR-GNB were characterized by pulsed-field gel electrophoresis (PFGE). Since November 2017 the following intervention measures were applied: (a) two-months intensification of sample collection; (b) stakeholders meetings; (c) improvement of prevention measures and antimicrobial policies. During the intensified microbiological surveillance MDR-GNB and ESBL-KP were detected in rectal swabs (34.8%; 23.2%), nasal swabs (24.6%; 14.5%), oral swabs (14.5%; 5.4%), milk samples (32.1%; 17.9%), pacifiers swabs (30.8%; 17.9%) and from sub-intensive room surfaces. Thirteen ESBL-KP strains isolated from clinical and environmental samples showed identical PFGE patterns. The prevalence of MDR-GNB and ESBL-KP carriage significantly decreased in the year after intervention compared to the previous year (20.6% vs 62.2%; p