EVALUATION OF POSTNATAL RENAL-FUNCTION IN FETUSES WITH BILATERAL OBSTRUCTIVE UROPATHIES BY PROTON NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY

OBJECTIVES: To precisely evaluate fetal renal function in cases of bilateral fetal urinary tract obstruction, we analyzed fetal urine metabolites by nuclear magnetic resonance spectroscopy. STUDY DESIGN: 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 greater than or equal to 1 year with normal serum creatinine (< 50 mu mol/L), for group 2 (n = 17) of survivors with abnormal serum creatinine (> 50 mu mol/L), and group 3 (n = 18) of those with bilateral histologic dysplasia associated with fetal (termination of pregnancy) or neonatal death. RESULTS: 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. CONCLUSIONS: In fetal bilateral urinary tract obstruction a fetal urine nuclear magnetic resonance profile allows an accurate identification of renal function at birth.