Uric acid is the end product of purine metabolism and is mainly produced by the enzymatic breakdown of nucleic acids and other purine analogues from cellular metabolism as well as purines from food. Hyperuricemia (HUA) is generally considered to be a condition in which fasting blood uric acid levels are higher than 420 μmol/L in men and 357 μmol/L in women on two non-same days under a normal purine diet. There are two main causes of high uric acid, namely increased uric acid production and decreased uric acid excretion, and sometimes both of them coexist. 1, increased uric acid production: mainly includes high purine dietary intake and endogenous purine metabolism production. Food-induced uric acid production is proportional to the purine content of food, and purine-rich foods include animal offal (liver, kidney, heart, brain, etc.), seafood (wind-tailed fish, sardines, fish eggs, small shrimp, etc.), and thick meat soup. The increase of endogenous purine metabolism in the body is mainly related to the abnormal synthesis and decomposition of purine and other factors. 2. Decreased uric acid excretion: About 2/3 of uric acid is excreted through the kidneys, and the remaining 1/3 is excreted through extrarenal pathways such as the intestine and bile duct. About 90% of patients with persistent hyperuricemia have defects in renal processing of uric acid and show reduced uric acid excretion, including reduced glomerular filtration rate, increased tubular reabsorption, reduced tubular secretion and impaired renal function due to deposition of uric acid crystals in the kidney. When uric acid continues to exceed the saturation concentration, urate crystals precipitate out and can be directly deposited in joints and surrounding soft tissues, renal tubules and blood vessels, etc. Long-term hyperuricemia can cause a series of serious hazards. 1, gout: gout is divided into asymptomatic phase, acute gouty arthritis and chronic phase, asymptomatic patients may not have any discomfort, only persistent or fluctuating elevation of blood uric acid, this period can last for several years or decades. The acute attack of gout is characterized by sudden onset of single joint redness, swelling and heat pain, mostly at night or in the morning during sleep, mostly in the joints of the lower extremities, the first metatarsophalangeal joint is the most common, but can also spread to the knees, fingers, wrists, elbows and other joints. At this time, the patient often feels that the joint swelling and pain is severe and unbearable, like a knife cut or insect bite. However, most of them are self-limiting, even without the use of drugs, the joint symptoms can be relieved within a few days or 2 weeks, or even disappear. 2, gout stone: if the condition is not well controlled, acute gout can be frequent attacks, uric acid crystals deposited in multiple parts of the body can gradually form swollen gout stone, often distributed in the auricle, foot, hand, elbow and other places, not only affect the appearance, and the presence of gout stone around the joint can erode the joint bone surface, resulting in chronic joint inflammation, resulting in persistent joint swelling, pain, and even joint deformity, affecting joint function. 3, uric acid nephropathy: ① Gouty nephropathy: uric acid salt deposited in the kidney can cause gouty nephropathy, resulting in hematuria, proteinuria, edema, anemia, hypertension, renal colic and other symptoms. ②Uric acid kidney stones: It can vary from no obvious symptoms to manifestations such as renal colic, hematuria, difficulty in urination, hydronephrosis, pyelonephritis or perinephritis. ③Acute renal failure: A large number of uric acid crystals block the renal tubules, renal pelvis and even ureter, and the patient suddenly develops oliguria or even anuria, which can develop into acute renal failure. Therefore, high blood uric acid is mainly caused by two types of reasons: increased uric acid production and reduced uric acid excretion, and long-term hyperuricemia can cause a series of serious consequences, so patients must pay attention to it and actively treat it to minimize the occurrence of adverse consequences.