Nephromegaly and elevated hepatocyte growth factor in children with biliary atresia

Nephromegaly, a rarely mentioned but probably common situation, was studied in children with biliary atresia. We evaluated the length and the cross-sectional diameters of the kidney by ultrasound in 21 children with biliary atresia as well as in 50 healthy children. The ages ranged from 1 month to 10 years. Plasma hepatocyte growth factor (HGF) was measured in 18 children with biliary atresia and also in 18 age- and sex-matched normal controls. There was a significant nephromegaly (increase in the renal length and the kidney volume) in children with biliary atresia as compared with normal children (P < 0.001 by analysis of covariance). Plasma HGF levels were elevated in these patients (2.13 +/- 1.06 v 0.76 +/- 0.19 ng/mL in controls, P < 0.001) and had a positive correlation with the renal size after considering the effect of body height by multiple regression analysis (P = 0.0022 for renal length, and P < 0.001 for kidney volume). These results confirm the presence of large kidneys in biliary atresia and implicate the possible pathogenic role of HGF in such a condition. Nephromegaly in biliary atresia may provide a new in vivo model to study the mechanism of renal growth.