Renin-angiotensin system dysregulation in fetuses with hydronephrosis.

OBJECTIVES

To evaluate if fetal hydronephrosis is associated with dysregulation of the renin-angiotensin system (RAS), and if it could represent an early predictor of future renal damage or arterial hypertension.

STUDY DESIGN

The study consisted of 26 pregnant women and their fetuses. Ultrasound scans were performed to evaluate the renal pelvis in fetuses. Four fetuses with hydronephrosis were included in the study, while the rest were found to have normal renal pelvis. Active and inactive renin was calculated by IRMA method in fetal and maternal blood, during the second trimester of pregnancy.

RESULTS

A comparison of plasma active and inactive renin levels was made between pregnant women and their fetuses, as well as between fetuses with and without hydronephrosis. Active and inactive renin levels obtained from fetuses with hydronephrosis were significantly higher compared to those obtained from fetuses with normal kidneys.

CONCLUSIONS

Dilatation of renal pelvis in the second trimester of pregnancy seems to up-regulate the renin and prorenin system in fetal blood. Both factors are indicative of possible future renal pathology.