No increase in GFAP and S-100B in very preterm infants with mild periventricular leukomalacia or intraventricular hemorrhage: a pilot study

AIM: To determine the serum levels of glial fibrillary acidic protein (GFAP) and S-100B in very preterm infants with and without periventricular leukomalacia (PVL) and/or intraventricular hemorrhage (IVH). METHODS: The study enrolled preterm infants born between 23 and 32 weeks of gestation admitted to the Neonatal Intensive Care Unit, University Medical Center Ljubljana. PVL and IVH were determined with cranial ultrasound. Peripheral blood was collected in the first 24 hours after delivery and once between days 4 to 7. GFAP and S-100B concentrations were measured in serum samples. Infants with PVL or IVH were compared with infants without PVL or IVH. RESULTS: Of 40 patients (mean gestational age 29.4 weeks), 7 had IVH and/or PVL. S-100B was detectable in peripheral blood in all patients at every measurement. In the group with IVH or PVL, the median S-100B at the first sampling was 0.43 (IQR 0.29-0.60) ng/mL, and 0.40 (IQR 0.33-1.01) ng/mL at the second sampling. In the group without PVL or IVH, it was 0.40 (IQR 0.29-0.6) ng/mL at the first sampling and 0.43 (IQR 0.34-0.62) ng/mL at the second sampling. The median GFAP was 0 regardless of the group and sampling time. The groups did not significantly differ in serum GFAP or S-100B levels. CONCLUSION: Peripheral blood levels of GFAP and S-100B were not significantly increased in very preterm infants that developed PVL or IVH. The predictive value of GFAP and S-100B as biomarkers of neonatal brain injury should be further explored in a larger cohort of neonates with more extensive IVH or PVL.