OBJECTIVETo investigate the incidence of late-onset sepsis (LOS) in very low birth weight (VLBW) and extremely low birth weight (ELBW) infants in the neonatal intensive care unit (NICU) and the risk factors for LOS.

METHODSA retrospective analysis was performed for the clinical data of all VLBW and ELBW infants who were hospitalized in the NICU between January 2011 and December 2013. According to the presence or absence of LOS, these infants were divided into LOS group and non-LOS group. The incidence and mortality rates of LOS, common pathogenic bacteria, and risk factors for LOS were analyzed.

RESULTSOf the 226 VLBW and ELBW infants, 117 (51.8%) developed LOS, among whom 45 had a confirmed diagnosis of LOS and 72 had a clinical diagnosis of LOS. The LOS group had a significantly higher mortality rate than the non-LOS group [13.7% (16/117) vs 4.6% (5/109); P<0.05]. Bacterial culture found 51 strains of pathogenic bacteria, among which 32 (63%) were Gram-negative bacteria, 16 (31%) were Gram-positive bacteria, and 3 (6%) were fungi. The multivariate logistic regression analysis showed that gestational age, small for gestational age (SGA), duration of parenteral nutrition, peripherally inserted central catheter (PICC) placement, and mechanical ventilation were independent risk factors for LOS in VLBW and ELBW infants (OR=0.84, 1.59, 1.34, 3.11, and 4.55 respectively; P<0.05).

CONCLUSIONSLOS has high incidence and mortality rates in VLBW and ELBW infants. Common pathogenic bacteria of LOS are Gram-negative bacteria. Low gestational age, long duration of parenteral nutrition, SGA, PICC placement, and mechanical ventilation may increase the risk of LOS in VLBW and ELBW infants.