Late onset bone marrow transplant nephropathy.

We report a patient who exhibited proteinuria and renal failure 93 months after receiving an allogeneic bone marrow transplantation (BMT) from his HLA-identical brother. A renal biopsy specimen revealed segmental sclerosis, mesangiolysis, subendothelial lucency in the glomeruli, fibrosis and small round cell infiltration in the interstitium, and hyaline droplets in the intimal spaces of arterioles and small arteries. These histological findings were consistent with late onset BMT nephropathy. This nephropathy may represent a more serious problem in the near future in Japan, since the number of BMT performed has been increasing with the establishment of a bone marrow bank.