Peripheral blood neutrophil-to-lymphocyte ratio in preterm infants with intraventricular hemorrhage

Abstract Objectives Intraventricular hemorrhage (IVH) remains a major complication of prematurity, affecting 20–25% of premature infants of very low birth weight. Preterm infants with IVH are at risk for developing significant complications, including posthemorrhagic hydrocephalus and seizures. Multiple studies have reported an association between the neutrophil-to-lymphocyte ratio (NLR) in peripheral blood and outcomes after acute intracranial hemorrhage in adults. However, the prognostic value of the NLR in preterm infants, particularly those with IVH, has not been investigated previously. Patients and methods This retrospective, observational cohort study included premature infants with IVH and a neonatal reservoir placed between January 2013 and January 2018. For each patient, peripheral blood and available cerebrospinal fluid laboratory results within 50 days of IVH diagnosis were averaged. NLR was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. Differences in NLR levels for patients with seizures or shunt placement were analyzed. Results Data for 13 surviving preterm infants (mean gestational age, 26.5 ± 3.0 weeks) were analyzed. The mean peripheral NLR (n = 13) was 1.6 ± 1.3 for all patients. Patients who experienced seizures had significantly higher peripheral blood NLR (p = 1.2 × 10 −6 , t-test) than those who did not, and an NLR > 3 correlated with seizure outcomes (p = 0.0035, Fisher’s exact). Patients with sepsis or meningitis also had NLR values >3 (p = 0.01 and 0.005, respectively) but there was no correlation between the sepsis/meningitis and seizures patients. No significant correlation was found between NLR and the development of hydrocephalus. Conclusion The development of seizures in preterm infants with IVH is known to significantly increase morbidity. In this study, higher peripheral blood NLR (>3) correlated with the development of seizures, independent of sepsis or meningitis. Further prospective validation of the role of NLR as a predictive marker for seizures in preterm infants is warranted.