[Oral purine loading test for latent metabolic disorders of uric acid in patients with calcium containing upper urinary calculi].

For the detection of metabolic disorders of uric acid in upper urolithiasis, an oral purine loading test was performed in 78 patients with calcium-containing calculi, 5 patients with uric acid calculi, and 34 stone free subjects. From the results of the normal subject group, the criteria of hyperuricemia, latent hyperuricemia, hyperuricosuria and latent hyperuricosuria were proposed. In calcium-containing stone formers, 6 male patients showed hyperuricosuria, 18 male patients and 4 female patients showed latent hyperuricemia or latent hyperuricosuria. In uric acid urinary stone formers, all cases showed latent hyperuricemia or latent hyperuricosuria. These findings indicated that the metabolic disorders of uric acid might be one of the risk factors for the formation of calcium containing urinary stones, as well as uric acid urinary stones.