A case of giant renal angiomyolipoma and diabetic nephropathy with abnormalities in the genes TSC2 and HNF1B.

A 57-year-old female patient with tuberous sclerosis and end-stage renal failure who had a history of diabetes mellitus and repeated renal hemorrhage after induction of dialysis underwent surgical nephrectomy. The renal tissue that caused the hemorrhage consisted of adipocytes, blood vessels, and smooth muscle cells, so angiomyolipoma was diagnosed. The cause of the hemorrhage was thought to be an abnormality in the vascular structure, i.e., disruption of the elastic plates that make up the vessel wall, and the presence of a hematoma in the same area. Diabetic nephropathy, which was observed in the atrophied native kidney, was presumed to be the cause of end-stage renal failure. Genetic analysis confirmed the presence of TSC2 mutation, which is linked to tuberous sclerosis, and HNF1B mutation, which is linked to diabetes. To our knowledge, this is the first report of a patient with HNF1B mutation who may have developed end-stage renal failure because of diabetic nephropathy and who also had histologic evidence of renal hemorrhage.