THE EPIDEMIOLOGY OF EARLY-ONSET VERSUS LATE-ONSET BLOODSTREAM INFECTIONS IN A NEONATAL INTENSIVE CARE UNIT.

Abstract

Bloodstream infections in neonates continue to be a significant ailment despite improvements in health care practice, most likely due to multiple risk factors affecting both early-onset and late-onset sepsis. Objective To compare the epidemiologic characteristics of early-onset and late-onset bloodstream infections in neonates treated at the University of California, Irvine neonatal intensive care unit (UCI-NICU) over a 7-year period. Methods All neonates with positive blood cultures treated at UCI-NICU between January 1998 and December 2004 were identified and their medical records were reviewed. Early-onset bacteremia was defined as an episode of bacteremia within the first 7 days of life. Results We identified 56 episodes of early onset and 160 episodes of late-onset bloodstream infections (see Table). Gram-negative bacteria caused bloodstream infections more frequently in early onset compared with late onset, whereas coagulase-negative Staphylococcus (CONS) was more common in late-onset infections. Comparing risk factors for patients with early-onset and late-onset bloodstream infections, as expected, those with early-onset infections were less likely to have had surgeries (5.4% vs 38%), prior antibiotic therapy (37.5% vs 90%), shorter duration of intubation (2 days vs 13.7 days), and shorter duration of central lines (3.7 days vs 28.7 days). Conclusions The predominant bacterial causes of early-onset and late-onset bloodstream infections are different. Elucidation of epidemiologic trends and risk factors associated with early- and late-onset bloodstream infections will have significant implications in developing measures to control the occurrence of these infections.