Evaluation of postnatal renal function in fetuses with bilateral obstructive uropathies by proton nuclear magnetic resonance spectroscopy.

Abstract

To precisely evaluate fetal renal function in cases of bilateral fetal urinary tract obstruction, we analyzed fetal urine metabolites by nuclear magnetic resonance spectroscopy. Fifty-six specimens of fetal urine samples in utero were retrospectively analyzed by proton nuclear magnetic resonance. Group 1 (n = 21) consisted of survivors for > or = 1 year with normal serum creatinine (< 50 mumol/L), for group 2 (n = 17) of survivors with abnormal serum creatinine (> 50 mumol/L), and group 3 (n = 18) of those with bilateral histologic dysplasia associated with fetal (termination of pregnancy) or neonatal death. A specific nuclear magnetic resonance profile was obtained for each of the three groups of renal function. A two-dimensional representation of alanine-valine and valine-threonine concentrations allows clear differentiation between the three degrees of renal function, with a sensitivity and specificity of 88% and 86%, respectively. In fetal bilateral urinary tract obstruction a fetal urine nuclear magnetic resonance profile allows an accurate identification of renal function at birth.