Differential diagnosis of fetal hyperechogenic cystic kidneys unrelated to renal tract anomalies: a multicenter study

Objectives To identify important factors in the differential diagnosis of renal cysts associated with hyper-echogenic kidneys. Methods This was a retrospective multicenter study. We identified 93 fetuses presenting between 1990 and 2002 with hyperechogenic kidneys and which bad a diagnosis of nephropathy confirmed later. We analyzed retrospectively the prenatal ultrasound findings of those fetuses which were found sonographically to have renal cysts. Results Of the 93 fetuses presenting with hyperechogenic kidneys and with a later diagnosis of nephropathy, there were 28 with autosomal dominant polycystic kidney disease (ADPKD), 31 with autosomal recessive polycystic kidney disease (ARPKD), 11 with Bardet-Biedl syndrome, nine with Meckel-Gruber syndrome, six with Ivemark 11 syndrome, one with Jarcbo-Levin syndrome, one with Beemer syndrome and one with Meckel-like syndrome. One third of the fetuses (30193) bad renal cysts. Cystic characteristics (size, location, number) were not very useful for diagnosis; more useful was diagnosis of an associated malformation. Three (11%) of the fetuses with ADPKD bad cysts, as did nine (29%) of those with ARPKD, three (27%) of those with Bardet-Biedl syndrome, all (100%) of those with Meckel-Gruber syndrome, three (50%) of those with Ivemark 11 syndrome, and each of the three cases with other syndromes (Jarcbo-Levin, Beemer and Meckel-like syndromes). None of the cases with trisomy 13 bad cysts. There were no associated malformations in the 12 cases with renal cysts and polycystic kidney disease; the other 18 cases with renal cysts were associated with malformations that were often specific, such as polydactyly in Bardet-Biedl and Beemer syndromes, occipital defect and Dandy-Walker malformation in Meckel-Gruber or Meckel-Gruber-like syndromes, and thoracic and/or vertebral abnormalities in Jarcbo-Levin and Beemer syndromes. Conclusion Renal cysts associated with hyperechogenic kidneys are not rare. The clue to diagnosis is the demonstration of an associated malformation. If no malformation is found, the main diagnosis remains polycystic kidney disease, i.e. ARPKD or ADPKD. Copyright (c) 2006 ISUOG. Published by John Wiley & Sons, Ltd.