Serum neutrophil gelatinase-associated lipocalin, total oxidant status, and total antioxidant status in preterm infants following clinical chorioamnionitis or preterm premature rupture of membranes: a multicenter prospective cohort study

Abstract

It is unclear whether the type of intrauterine inflammatory exposure influences global oxidant/antioxidant status or neutrophil gelatinase-associated lipocalin (NGAL) in preterm infants. Methods: Ninety-four infants born before 32 weeks of gestation were enrolled prospectively at three centers and grouped as clinical chorioamnionitis (n = 31), preterm premature rupture of membranes (PPROM; n = 33), or controls (n = 30) delivered preterm chiefly for preeclampsia, growth restriction, or placental insufficiency. Groups were not matched, but gestational age and birth weight were comparable. Serum total oxidant status (TOS), total antioxidant status (TAS), and NGAL were measured at the 1st postnatal hour. Results: TAS, TOS, and the oxidative stress index did not differ among groups (p = 0.966, 0.525, and 0.729). NGAL differed (p = 0.031) and was lowest in the clinical chorioamnionitis group, confined to the clinical chorioamnionitis-versus-PPROM contrast (adjusted p = 0.029) and persisting after multivariable adjustment. After correction for multiple testing, no biomarker correlated with C-reactive protein, blood counts, or procalcitonin at the 1st or 24th postnatal hour, or with the first-hour Töllner sepsis score; the strongest single association was NGAL with the first-hour neutrophil count (ρ = 0.29). Necrotizing enterocolitis was more frequent in controls (p = 0.003); mortality (20.2%) did not differ among groups. Conclusions: A single early measurement of these biomarkers did not reliably classify the type of intrauterine inflammatory exposure; discrimination was modest (area under the curve, 0.689), so serum NGAL has no current clinical applicability. These hypothesis-generating findings require confirmation in adequately powered studies with serial sampling.