Background: Coagulase-negative staphylococci (CoNS) are the most commonly isolated pathogens in the neonatal intensive care unit (NICU). CoNS infections are associated with increased morbidity, including neurodevelopmental impairment.
Objective: To describe the epidemiology of CoNS infections in the NICU. To determine mortality among infants with definite, probable, or possible CoNS infections.
Methods: We performed a retrospective cohort study of all blood, urine, and cerebrospinal fluid cultures from samples obtained from infants aged <121 postnatal days.
Setting: A total of 248 NICUs managed by the Pediatrix Medical Group from 1997 to 2009.
Results: We identified 16,629 infants with 17,624 episodes of CoNS infection: 1,734 (10%) definite, 3,093 (17%) probable, and 12,797 (73%) possible infections. Infants with a lower gestational age and birth weight had a higher incidence of CoNS infection. When controlling for gestational age, birth weight, and 5-minute Apgar score, we found that infants with definite, probable, or possible CoNS infection had lower mortality (odds ratio [OR], 0.74 [95% confidence interval {CI}: 0.61, 0.89], 0.68 [95% CI, 0.59, 0.79], and 0.69 [95% CI, 0.63, 0.76], respectively) compared with infants who had negative culture results (P = .001). No significant difference in overall mortality was found in infants who had definite CoNS infection compared with those who had probable or possible CoNS infection (OR, 0.93 [95% CI, 0.75, 1.16] and 0.85 [95% CI, 0.70, 1.03], respectively).
Conclusions: CoNS infection was strongly related to lower gestational age and birth weight. Infants with clinical sepsis and culture-positive CoNS infection had lower mortality rates than infants with clinical sepsis and negative blood culture results. No difference in mortality between infants with a diagnosis of definite, probable, or possible CoNS infection was observed.