[Reversible acute renal failure with tubular oxalosis. Possible role of nutritional factors].

Intratubular deposits of calcium oxalate crystals can be responsible for acute renal failure. The present report concerns two cases for which none of the known causes of oxalate nephropathy were found. Both patients had common features: chronic alcoholism and denutrition. Except for early lumbar and abdominal pain, the renal failure picture was without any peculiarity. Renal biopsy showed tubular epithelium alterations with marked luminal deposition of birefringent crystals consistent with calcium oxalate. In one patient serum oxalate level was high, and in the other urinary oxalate excretion rose above normal when diuresis resumed. Renal function recovered spontaneously (follow-up of four years for one patient). Neither intoxication nor intestinal disease could be detected. Given the key role of pyridoxine in oxalate metabolism, we suggest that vitamin B6 deficiency secondary to alcoholism and denutrition could cause a rise in oxalemia leading to oxalate nephropathy. Experiments in animals support this hypothesis.