Methods: This was a retrospective, descriptive study utilizing laboratory culture and susceptibility data for all blood, urine, cerebrospinal fluid, and respiratory isolates obtained from subjects admitted to the NICU between January 1, 2010 and December 31, 2014. The NICU antibiogram describes the susceptibility of all tested antimicrobials and was created in accordance with CLSI guidelines; susceptibility patterns were compared to the standard hospital antibiogram. Additionally, patient characteristics and risk factors were analyzed with descriptive statistics to identify trends in susceptibility.
Results: A total of 433 cultures were analyzed from 227 subjects. The majority of subjects weighed <1000g at birth (56.8%), were <29 weeks (66.5%) gestational age, and received >72 hours of antimicrobial therapy (70.4%) prior to positive culture. The most commonly identified organisms included E. coli (N=73, 17%), S. aureus (N=64, 15%), and coagulase-negative staphylococcus (N=64, 15%). E. coli was significantly less susceptible to ampicillin in the NICU vs. hospital (29% vs. 47%, p=0.048) but, remained similarly susceptible to gentamicin (85% vs. 90%, p=0.674). Of the E. coli isolates, 4/73 were associated with early-onset sepsis and 100% were resistant to ampicillin; 1/4 also resistant to gentamicin. S. aureus remained more susceptible to oxacillin in the NICU vs. the hospital (86% vs. 61%, p=0.08).
Conclusion: These data further emphasize the need for developing NICU-specific antibiograms to optimize empiric antimicrobial therapy as susceptibility differs compared to the hospital. When combined with patient factors, utilizing NICU antibiogram data may allow for more rapid targeted antimicrobial therapy.
N. Rabs, None
R. Oram, None