Hyperuric acid metabolism is caused by hyperuricemia. To determine whether hyperuricemia is an excess of synthesis or impaired excretion, uric acid clearance, uric anhydride clearance or urinary uric acid concentration and urinary uric anhydride concentration should be checked. The ratio of urinary clearance and uric anhydride clearance: below 5% is uric acid excretion disorder, 5%~12% is mixed type, i.e. both increased uric acid production and uric acid excretion disorder, above 12% is excessive uric acid synthesis. The following are the main points of diagnosis: 1. It is mostly seen in middle-aged male patients who have frequent episodes of gouty arthritis or have gouty nodules or uric acid urinary tract stones. 2, urine and kidney function tests show chronic interstitial nephritis. 3, Increased uric acid in blood, male >420umol/L, female >360umol/L, uric acid enzyme method. 4, acute uric acid nephropathy is seen in malignant tumor chemotherapy, often manifested as acute renal failure.