Determinants of nosocomial infection in 6 neonatal intensive care units: an Italian multicenter prospective cohort study.
BACKGROUND
Nosocomial infections are still a major cause of morbidity and mortality among neonates admitted to neonatal intensive care units (NICUs).


OBJECTIVE
To describe the epidemiology of nosocomial infections in NICUs and to assess the risk of nosocomial infection related to the therapeutic procedures performed and to the clinical characteristics of the neonates at birth and at admission to the NICU, taking into account the time between the exposure and the onset of infection.


METHODS
A multicenter, prospective cohort study.


METHODS
A total of 1,692 neonates admitted to 6 NICUs in Italy were observed and monitored for the development of nosocomial infection during their hospital stay.


METHODS
Data were collected on the clinical characteristics of the neonates admitted to the NICUs, their therapeutic interventions and treatments, their infections, and their mortality rate. The cumulative probability of having at least 1 infection and the cumulative probability of having at least 1 infection or dying were estimated. The hazard ratio (HR) for the first infection and the HR for the first infection or death were also estimated.


RESULTS
A total of 255 episodes of nosocomial infection were diagnosed in 217 neonates, yielding an incidence density of 6.9 episodes per 1,000 patient-days. The risk factors related to nosocomial infection in very-low-birth-weight neonates were receipt of continuous positive airway pressure (HR, 3.8 [95% confidence interval {CI}, 1.7-8.1]), a Clinical Risk Index for Babies score of 4 or greater (HR, 2.2 [95% CI, 1.4-3.4]), and a gestational age of less than 28 weeks (HR, 2.1 [95% CI, 1.2-3.8]). Among heavier neonates, the risk factors for nosocomial infection were receipt of parenteral nutrition (HR, 8.1 [95% CI, 3.2-20.5]) and presence of malformations (HR, 2.3 [95% CI, 1.5-3.5]).


CONCLUSIONS
Patterns of risk factors for nosocomial infection differ between very-low-birth-weight neonates and heavier neonates. Therapeutic procedures appear to be strong determinants of nosocomial infection in both groups of neonates, after controlling for clinical characteristics.
Auriti
Cinzia
C
Neonatal Intensive Care Unit, Bambino Gesù Children's Hospital, Istituto Di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy. cinzia.auriti@opbg.net
Ronchetti
Maria Paola
MP
Pezzotti
Patrizio
P
Marrocco
Gabriella
G
Quondamcarlo
Anna
A
Seganti
Giulio
G
Bagnoli
Francesco
F
De Felice
Claudio
C
Buonocore
Giuseppe
G
Arioni
Cesare
C
Serra
Giovanni
G
Bacolla
Gianfranco
G
Corso
Giovanna
G
Mastropasqua
Savino
S
Mari
Annibale
A
Corchia
Carlo
C
Di Lallo
Domenico
D
Ravà
Lucilla
L
Orzalesi
Marcello
M
Di Ciommo
Vincenzo
V
D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology; D001724:Birth Weight; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D005865:Gestational Age; D006785:Hospitals, University; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data*; D007558:Italy / Q000453:epidemiology; D007902:Length of Stay; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D018805:Sepsis / Q000453:epidemiology* / Q000382:microbiology; D013997:Time Factors