Surveillance of healthcare-associated infections in a neonatal intensive care unit in Italy during 2006–2010

Crivaro et al. BMC Infectious Diseases Surveillance of healthcare-associated infections in a neonatal intensive care unit in Italy during 2006-2010 Valeria Crivaro 0 3 Lidija Bogdanovi 0 Maria Bagattini 0 Vita Dora Iula 2 Mariarosaria Catania 2 Francesco Raimondi 4 Maria Triassi 0 Raffaele Zarrilli 0 1 0 Department of Public Health, University of Naples Federico II , Naples , Italy 1 Italian Study Group of Hospital Hygiene, Italian Society of Hygiene, Preventive Medicine and Public Health , (GISIO), Rome , Italy 2 Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II , Naples , Italy 3 AORN dei Colli, Monaldi Hospital , Via L. Bianchi, Naples , Italy 4 Division of Neonatology, Department of Medical Translational Sciences, University of Naples Federico II , Naples , Italy Background: Healthcare-associated infections (HAIs) are a frequent complication associated with hospitalization of infants in neonatal intensive care units (NICUs). The aim of this study was to evaluate and describe the results of surveillance of HAIs in a III level NICU in Naples, Italy during 2006-2010. Methods: The surveillance covered 1,699 neonates of all birth weight (BW) classes with > 2 days NICU stay. Infections were defined using standard Centers for Disease Control and Prevention definitions adapted to neonatal pathology and were considered to be healthcare-associated if they developed > 2 days after NICU admission. Results: One hundred-fifty-three HAIs were diagnosed with a frequency of 9% and an incidence density of 3.5 per 1000 days of hospital stay. HAIs developed in all BW classes, but patients weighing 1000 g at birth were more affected with a decreasing trend from the lowest to the highest BW classes. Sepsis proved to be the most frequent infection (44.4%), followed by urinary tract infection (UTI) (28.8%), pneumonia (25.5%) and meningitis (1.3%). Device associated infections (i.e. central line-associated bloodstream infections (BSIs), umbilical catheter-associated BSI and ventilator associated pneumonias (VAPs) represented 64.1% of all HAIs. Most frequent pathogens responsible for all types of infections were: P. aeruginosa (17%), C. parapsilosis (16.3%), E. coli (13.1%), C. albicans (10.5%), non- extended spectrum beta-lactamase (ESBL) K. pneumoniae (7.8%), and coagulase-negative Staphylococci (5.2%). No microbiological diagnosis was achieved for 6.5% of infections. Conclusions: HAIs developed in all BW classes but low BW neonates were at major risk to acquire HAIs in our NICU. Use of central line-, umbilical-catheter and mechanical ventilation was associated with higher risk of infection. Our findings highlight the importance of an extensive surveillance approach in the NICU setting, which includes all BW classes of neonates and monitors infections associated with the use of medical devices. Neonatal intensive care units; Healthcare-associated infections; Active surveillance - Background Healthcare-associated infections (HAIs) are frequent and critical complications associated with hospitalization of neonates, especially very low birth weight (VLBW) neonates, in neonatal intensive care units (NICUs) [1,2]. Active surveillance systems for HAIs in NICUs have been developed in USA and Canada by the National Healthcare Safety Network (NHSN) [3,4], the Vermont Oxford Network [5,6] and the Canadian Neonatal Network [7]. In Europe, surveillance systems for HAIs in NICUs are active in Germany [8,9] and in England [10]. The first national report on HAIs in Italian intensive care units (ICUs) has recently been published [11]. The document shows the results of HAIs surveillance activities for the 20092010 period and mainly focuses on adult ICUs, with a very limited contribution of pediatric ICUs and none of NICUs. While several studies have shown the spread of specific nosocomial pathogens, such as ESBL producing Enterobacteriaceae [12,13], Pseudomonas aeruginosa [14], methicillin resistant Staphylococcus aureus [15], extensively drug resistant (XDR) Acinetobacter baumannii [16], Candida parapsilosis [17] in Italian NICUs, few studies were performed on the prevalence [18] or incidence of HAIs in NICUs [19-21]. Active surveillance of HAIs was utilized in the majority of the studies from Italian NICUs [12-16,18,21]. Objective of the present study was to describe and discuss the results of surveillance of HAIs in a neonatal intensive care unit in Italy during 20062010 using the NHSN surveillance protocol. Methods Setting The University of Naples Federico II NICU is a III level NICU with a total of 25 incubators and cradles. The ward serves the University Obstetric Clinic (approximately 2000 births/year) which is both a high risk pregnancy center and an obstetric emergency service. Moreover, the NICU admits outborn neonates from the regional Newborn Emergency Transport Service. Active surveillance Healthcare-associated infections (HAIs) active, patientbased surveillance (AS) is continuously carried out by trained personnel. Data are collected on weekly basis directly from patients charts. Any clinical issues are directly discussed with caregivers. Data are analyzed on monthly basis and expressed as monthly report. Monthly report consist of patient data, data on swab isolations of sentinel pathogens, device utilization ratios and infection data. All neonates with > 2 days NICU stay enter the AS system and data regarding birth (birth weight (BW), gestational age, type of delivery, and Apgar score), invasive device exposure (days of umbilical and central line catheterization and of invasive ventilation), antimicrobial therapy exposure (yes/no) and infections are collected. End of surveillance coincides with neonates discharge from the ward. Infections are defined using standard Centers for Disease Control and Prevention definitions adapted to neonatal pathology [22-24] and are considered to be healthcareassociated if they develop > 2 days after NICU admission. We exclude neonates with a vertical infection (ie, an infection transmitted from mother to child) or infection acquired during delivery. This paper analyzes data from the HAIs AS system over a 5 years long period (20062010). For this study purposes, only sepsis, meningitis, pneumonia, and urinary tract infections (UTIs) were considered. Central line-associated blood-stream infections (BSI), umbilical catheter-associated BSI and ventilator-associated pneumonia (VAP) were attributed if a central line, an umbilical catheter and invasive ventilation, respectively, were in place at the time of or within 48 hours before infection onset [24]. Frequency measures were calculated as percent of infection and as incidence densities, i.e. infection rates per 1000 days of hospital stay or 1000 days of directly related invasive device within 5 BW classes (750 g, 7511000 g, 10011500 g, 15012500 g, and 2501 g). Device utilization rates within such classes were also calculated. The etiology of all infec (...truncated)