Mild metabolic hyperoxaluria and its response to pyridoxine

Three cases of mild metabolic hyperoxaluria (with glycollaturia) are described. They showed different types of response to pyridoxine. One responded to low dose, one responded at first to low dose but became resistant, and the third showed temporary response to high dose. One case also had primary hyperparathyroidism and one had medullary sponge kidneys and hypercalciuria. It is important to measure urinary oxalate (and glycollate) in all cases of calcium oxalate urolithiasis.