A simultaneous liver-kidney transplant recipient with IgA nephropathy limited to native kidneys and BK virus nephropathy limited to the transplant kidney.

Immunoglobulin A (IgA) deposition in the native kidneys of patients with liver disease is well described. Secondary IgA nephropathy usually is thought to be benign, but hematuria, proteinuria, and loss of kidney function have been reported in this context. BK virus nephropathy is an important cause of kidney transplant loss; however, BK virus nephropathy is rare in the native kidneys of patients who underwent transplantation of other organs. We report the case of a patient with alcohol-related end-stage liver disease and chronic kidney disease with hematuria who underwent simultaneous liver-kidney transplantation. His kidney function decreased over the course of several weeks posttransplantation. Biopsy of the transplant kidney showed BK virus nephropathy, but no IgA deposits. In contrast, biopsy of the native kidneys showed IgA deposits, but no BK virus nephropathy. To our knowledge, this is the first reported case of a simultaneous liver-kidney transplantation wherein both the native and transplant kidneys were biopsied posttransplantation and showed exclusively different pathologies. These findings confirm the predilection of BK virus nephropathy for transplant rather than native kidneys.