[Diagnosis and therapy of fetal kidney and urinary tract malformations].

Of 23 patients with abnormal prenatal sonographic findings 17 also showed malformations of the kidneys and urinary tract in the postpartal period. Although even minor abnormalities could be detected by antenatal ultrasound, the identification of the abnormal findings was not possible in every case. Diagnostic problems arose in 8 foetuses showing mild dilatation of the collecting system, since it was not possible to distinguish between functional dilatation and dilatation from vesicoureteral reflux or minimal ureteral obstruction. Difficulties in identification of large malformations also occurred in 3 other patients, if the first sonographic examination was performed in a late stage of pregnancy, so that no follow-up of the sonographic picture was possible. In one of these children a huge right-sided multicystic kidney resulted in compression of the contralateral ureter with hydronephrosis, damaging the other kidney. Early delivery should, therefore, be considered in all children showing large cystic abdominal masses and no identifiable normal kidney, so that adequate obstetric treatment of these patients can be initiated in time.