Changes in retinol binding protein and beta-2-microglobulin levels in the netilmicin administered newborns with hyperbilirubmemia

Abstract

It is considered that hyperbilirubinemia affects renal functions in newborns. Increased levels of retinol binding protein (RBP) and ?2 microglobulin in urine are used as indicators of proximal tubular dysfunction. The purpose of this study is to determine the changes in tubular functions in newborns with hyperbilirubinemia who were administered netilmicin prophlaxis. Sixty jaundiced newborns with gestational ages ranging from 38 to 42 weeks and with similar postnatal ages (in the first 10 days of life) were included in the study. Fifteen healthy newborns were selected as a control group. In newborns with indirect hyperbilirubinemia and in the control group, measuring blood urea nitrogen (BUN), serum creatinin, creatinin clearance (Ccr), fractional excretion of sodium (FE(Na)) serum and urine osmolarity, RBP and ?2 microglobulin concentrations in urine, renal functions were examined. In this study, the results showed that the effect of indirect hyperbilirubinemia over RBP and ?2 microglobulin concentrations in urine did not increase with prophlactic administration of netilmicin in newborn period. In addition, no difference was observed in the levels of RBP and ?2 microglobulin in urine between nephrotoxic drug administered (group I(A): Ampicillin 100 mg/kg/day I.M in four doses + Netilmicin 5 mg/kg/day I.M in two doses, group I(B): Ampicillin 100 mg/kg/day I.M in four doses + Netilmicin 5 mg/kg/day I.M in one dose) and non-nephrotoxic drug administered groups (group I(C): Ampicillin 100 mg/kg/day I.M in four doses).