[Adult type I primary hyperoxaluria: 2 cases confirmed by liver biopsy at end-stage renal insufficiency]

It can be difficult to distinguish between primary hyperoxaluria at end-stage renal failure and secondary oxalosis, all the more as primary hyperoxaluria can be latent for a long time and occur at a late stage. A 57 year-old woman, without family nor personal history of urolithiasis, receives regular hemodialysis for a renal failure discovered at end-stage. Eighteen months later, calcium oxalate deposits appear in the skin, bone marrow and both kidneys, suggesting secondary oxalosis. An other 57 year-old woman presents a chronic renal failure due to bilateral urolithiasis, whose surgery has caused a dramatic decrease of renal function requiring regular hemodialysis. Because of apparition of severe bone alterations, a parathyroidectomy is realized, and because of calcium oxalate deposition in the skin and bone marrow, primary hyperoxaluria is suspected. In both observations, the enzyme activity determination in a liver biopsy gives the diagnosis of primary hyperoxaluria.