Changes in Epidemiology of Neonatal Sepsis according to Rapid Expansion of a Tertiary Neonatal Intensive Care Unit: Trends over 18 Years

Abstract

Objectives: We investigated changes in the admission patterns of neonatal intensive care units (NICU) and the epidemiology of neonatal sepsis following the rapid expansion and improvements in neonatal intensive care.

Methods: Data regarding the admission of neonates with culture-proven sepsis between 1996 and 2013 (period I: 1996-2005, period II: 2006-2013) were collected retrospectively.

Results: The admission of extremely low birth weight (ELBW) infants increased between periods I and II (11.1 vs. 28.7 infants per 1,000 live births, P < 0.001). The survival rate of the ELBW infants improved (57.5 vs. 80.1%, P < 0.001), and their duration of hospital stay increased (median days: 64 vs. 80, P = 0.001). The incidence of sepsis among all infants and ELBW infants increased (all infants, 5.9 vs. 12.7 cases per 1,000 live births

ELBW infants, 189.5 vs. 290.1 cases per 1,000 live births). In ELBW infants, the incidence of sepsis caused by coagulase-negative Staphylococcus (CONS), significantly increased during period II (8.8 vs. 25.4%, P = 0.039). By multivariate analysis, central vascular catheters and prolonged hospitalization were independently associated with increased sepsis rate, particularly CONS in ELBW infants.

Conclusions: The inborn admission rate for ELBW infants has increased significantly and is accompanied by improved survival and longer hospital stays. The incidence of neonatal sepsis, particularly in ELBW infants, has also increased, and CONS has emerged as a major pathogen. Our data suggested that central vascular catheters and prolonged hospitalization could be independent risk factors for the increased sepsis rate, particularly sepsis due to CONS.