Case-control analysis of endemic Acinetobacter baumannii bacteremia in the neonatal intensive care unit

Abstract

We aimed to characterize the clinical manifestations and outcomes of patients with Acinetobacter baumannii bacteremia in the neonatal intensive care unit (NICU). All patients with A baumannii bacteremia in our NICU from 2004 to 2010 were reviewed. A matched case-control study was performed by comparing each case of A baumannii to 2 uninfected controls and all cases of Escherichia coli and Klebsiella bacteremia, respectively. Thirty-seven cases with A baumannii bacteremia were identified. Multidrug-resistant isolate was noted in only 2 cases (5.4%), and the overall mortality rate was 8.1%. Compared with matched, uninfected controls, infants with A baumannii were more likely to have had a central vascular catheter (CVC) (P= .009), use of total parenteral nutrition (TPN) (P= .021), longer duration of ventilator use (P= .002), and hospitalization (P= .010). Compared with E coli or Klebsiella bacteremia, infants with A baumannii bacteremia had lower birth weight (median of 1,090 g vs 1,300 g, P= .044) and a higher rate of CVC and TPN use (both P < .001) at the time of infection. A baumannii bacteremia occurs endemically or sporadically in the NICU, primarily in low-birth-weight infants on TPN use and with CVC in situ. Although A baumannii does not often cause mortality, and multidrug-resistant A baumannii is uncommon, it contributes significantly to longer hospitalization.