24-Hour Urine Uric Acid Test

A quantitative test measures the total amount of uric acid excreted in the urine over a 24-hour period. It aims to assess purine metabolism in the body and classify hyperuricemia into two types: overproducers/overexcretors, where urinary excretion is high, and underexcretors, where urinary excretion is normal or low despite elevated blood uric acid levels. This classification is crucial for diagnosing the cause of uric acid stones and guiding treatment (such as using medications like allopurinol for overproducers, or urinary alkalizers for underexcretors).