Acquired renal cystic disease after liver transplantation in children.

To our knowledge, the development of renal cystic disease that may contribute to kidney dysfunction has never been reported after liver transplantation. Herein we have reported on the fortuitous finding of renal cystic lesions upon computed tomographic scans (CT) in 33 (30%) of 108 pediatric liver transplant recipients who were the subjects of a prospective study evaluating long-term kidney dysfunction at 10 years after liver transplantation. The renal lesions had 2 different appearances: that of simple renal cysts and that of round lesions that were spontaneously hyperdense before contrast injection. These high-density lesions had a low signal on T2 weighted sequences, but 70% of them had been missed at ultrasonography. Their aspect upon CT and magnetic resonance favored cystic lesions filled with hemorrhagic or milk calcium content. Both types of cystic lesions were associated in 14 children. The renal lesions were significantly associated with moderate renal dysfunction, biopsy-proven chronic liver graft rejection, and thrombosis of the retrohepatic vena cava. The physiopathology of these lesions is undetermined. Two important questions need to be clarified with respect to the risk of progression of renal dysfunction associated with individual volume changes and/or increased number of renal cysts, as well as the risk of renal cancer as has been reported in dialyzed patients with acquired cystic kidney disease.