Effect of Perinatal Asphyxia and Gentamicin on Urinary B2-microglobulin Concentration and Renal Function in Fullterm Neonates

ABSTRACT

Perinatal asphyxia can cause ischemic injury to immature kidney of neonates. Proximal renal tubule is the most sensitive area, showing various manifestations ranging from mild reversible injury to irreversible tubular necrosis. Aminoglycosides can be nephrotoxic in therapeutic range in immature or damaged kidney. Thess are the very important factors to be taken into corsideration on fluid therapy and nephrotoxic drugs in neonates. The purpose of this study is to detect renal dysfunction resulting from asphyxia and gentamicin treatment. The results were as follows; 1) Urinary 2-microglobulin concentration was significantly higher in neonatal asphyxia group irrespective of meconium stain (p0.05). The group with neonatal asphyxia and meconium stain (Ib) received gentamicin for 7 days. Their urinary 2-microglobulin concentration dropped on 4 the day and increased again on 7 th day (p0.05). 2) No differences were shown in serum creatinine, serum sodium level and urinary creatinine concentrations between each group (p>0.05). 3) No differences were shown in creatinine clearance between each group (p>0.05).Fractional excretion of urinary sodium (FENa) was significantly higher on lst day in group, I, but no differences were shown afterwards (p>0.05). 4) There is no relationship between urinary 2-microglobulin concentration and serum creatinine level, creatinine clearance of FENa. 5) No differences were shown in incidence of renal dysfunction between each group. In conclusion, acute tubular injury by perinatal asphyxia recovered soon after birth. But nephrotoxic gentamicin worsened the recovering tubular injury. In case of mild fetal hypoxia without neonatal asphyxia, proximal tubular injury was not significant.