Conservative management of urinary abnormalities detected in utero.

During a 5-year period, we observed 48 fetuses with urinary malformations diagnosed by antenatal sonography. Postnatal investigations confirmed the presence of a urinary tract anomaly in 44 of the 48 fetuses selected by prenatal ultrasound (91%). Accurate antenatal diagnosis was made in 35 of the 48 cases (73%). In 9 fetuses renal disease was detected, but its specific nature was not in accordance with the prenatal diagnosis. In our series the most common anomaly was hydronephrosis secondary to ureteropelvic junction obstruction. This condition was observed in 31 of the 44 patients (70.4%); 7 of the newborns who showed an obstructive pattern were submitted to early surgical repair, while the remaining 24 cases and 1 renal unit of the group undergoing early surgical repair were relegated to expectant observation, with periodic clinical and laboratory controls. A spontaneous recovery was observed in 12 cases; the dilatation remained unchanged in 10 cases, while 3 patients showed a progressive worsening of the condition which led to a surgical correction. Our findings agree with those in recent reports in providing little support for early, indiscriminate surgical repair. Moreover, our experience confirms the possibility of a spontaneous recovery in newborns with hydronephrosis and draws attention to the benefit of a conservative management in properly selected patients.