Combined liver-kidney transplantation in primary hyperoxaluria type 1. Bone histopathology and oxalate body content.

In three patients with end-stage renal failure due to primary hyperoxaluria type 1, successful combined liver-kidney transplantation enabled us to assess the insoluble oxalate pool, which was compared with the histopathological changes observed in iliac crest biopsy specimens. Good correlation was observed between the histopathological grade of bone oxalosis and the estimated oxalate content of the body. In the end-stage of oxalate bone disease, hyperparathyroidism does not play a significant role in bone resorption, which appears to be the consequence of the granulomatous reaction induced by oxalate deposition. Combined liver-kidney transplantation should be performed long before this stage. Early hepatorenal grafting in uremia secondary to primary hyperoxaluria type 1 would avoid the deleterious clinical consequences of systemic oxalosis and shorten the duration of postransplant hyperoxaluria, which may compromise the course of kidney graft.