Assessment of serum levels of alpha-1-microglobulin, beta-2-microglobulin, and retinol binding protein in the fetal blood. A method for prenatal evaluation of renal function.

The concentrations of alpha-1-microglobulin, beta-2-microglobulin, and retinol binding protein were determined in fetal blood sampled by cordocentesis. The blood values of 126 fetuses without ultrasonographic findings of urinary tract abnormalities as controls were found to be independent of the week of gestation. In nine fetuses affected by a severe bilateral renal dysplasia or agenesis, elevated values of alpha-1-microglobulin but normal values of retinol binding protein were obtained. The authors recommend the determination of alpha-1-microglobulin and, with some restriction, also of beta-2-microglobulin in prenatal renal function diagnosis.