Renal malformations in children with Turner's syndrome.

Between 1988 and 1999, renal sonography and intravenous urography were performed to detect renal malformations in 54 patients with Turner's syndrome (TS). The mean age of these patients at diagnosis of TS was 9.2 +/- 4.6 years. Renal malformations were detected in 21 patients by intravenous urography and there was no significant difference in the frequency of renal malformations among different karyotype groups. Horseshoe kidney was the most common renal malformation, followed by duplex kidney. Fifteen of 21 renal malformations were not detected by renal sonography. We conclude that these TS patients had a high frequency of renal malformations, and that the detection rate of horseshoe kidney and duplex kidney by renal sonography was not satisfactory. Although renal sonography alone can be used to detect more severe renal malformations that may need further management, it may underestimate the frequency of renal malformation in children with TS.