Glyoxylate Metabolism in Normal and Stone-Forming Humans and the Effect of Allopurinol Therapy

After injection of glyoxylate-14C, detectable amounts of glyoxylate appeared in the urine for less than 1 hour. The radioactivity primarily appeared as longer persisting oxalate with a minor proportion of very transient glycolate. The rate of conversion and the proportion of the administered radioactivity recovered in 2 hours was closely similar for both normal controls and severely recurrent oxalate stone formers and was unaffected in the latter by allopurinol therapy.