Antenatal diagnosis of bilateral polycystic kidney disease in a twin pregnancy.

Polycystic renal dysplasia is a lethal malformation when it is bilateral. T he authors report a rare case of polycystic dysplasia observed in both foet uses of a twin pregnancy, one of whom survived despite bilateral polycystic kidney disease. These biamniotic monoplacental twins were delivered premat urely at 33 weeks of amenorrhoea. The diagnosis was made by antenatal ultra sound. The first twin presented bilateral renal lesions : right polycystic kidney, segmental polycystic dysplasia of the superior pole of the left kid ney on a completely duplicated system. The second twin presented a right po lycystic kidney. In the light of this case report, the authors describe the various antenatal presentations of polycystic kidney and the associated ur ological malformations. Involvement of both foetuses of a twin pregnancy ra ises a discussion of the aetiopathogenesis of polycystic renal dysplasia.