The product of normal human urine is mainly urea and contains a small amount of uric acid. Uric acid is the end product of purine metabolism. Trioxy purine, its alcohol formula is weakly acidic. The uric acid produced after oxidation of various purines is excreted in the urine. Due to the small solubility, urinary tract stones or gout can be formed when the body is too much.

 

Uric Acid Causes

 

First, the metabolic disorder of purine substances in the body, resulting in increased uric acid synthesis.

 

1, purine intake too much: high levels of uric acid and food purine content is proportional to. 50% of RNA in food intake and 25% of DNA in urine

 

In the form of uric acid excretion, strictly limit the purine intake can reduce the serum uric acid content to 60μmol/L (1.0mg/dL), while the secretion of uric acid in the urine is reduced to 1.2mmol/d (200mg/d).

 

2. Excessive production of endogenous purines: Endogenous purine metabolic disorders are more important than exogenous factors. The de novo synthesis of purines from acyclic to cyclic decomposes through 11 steps, in which anomalous enzyme causes excessive purine synthesis. What have been discovered so far are:

 

1) Increased activity of phosphoribosyl pyrophosphate synthetase.

 

2) Hypoxanthine-guanine phosphoribosyl transferase deficiency.

 

3) Glucose 6-phosphatase deficiency.

 

3, increased purine metabolism: such as chronic hemolytic anemia, rhabdomyolysis, polycythemia, myeloproliferative diseases and chemotherapy or radiotherapy will produce high uric acid. Hyperkinesia, epilepsy, and types III, V, and VII of glycogen storage disease all accelerate muscle ATP degradation. Myocardial infarction, smoking, and acute respiratory failure are also associated with accelerated degradation of APT.

 

 

Second, the metabolic disorder of purine substances in the body, leading to the reduction of uric acid excretion. 90% of patients with persistent high uric acid have abnormal renal function of uric acid treatment.

 

In patients with hyperuricemia and gout, given different uric acid loads, the ratio of urate clearance to glomerular filtration rate was lower than in the normal population. The reduction in uric acid secretion may be related to decreased glomerular filtration rate, reduced tubular secretion, or tubular reabsorption. Although uric acid high is always present in chronic kidney disease, the relationship between uric acid concentration and serum creatinine and blood urea nitrogen is unclear.

 

With the decline of renal function, the amount of uric acid secretion per unit of glomerulus is increased, but the secretion capacity of renal tubule is basically unchanged, the reabsorption capacity of renal tubule is also reduced, and the clearance capacity of extra-renal uric acid is significantly increased.

 

1. The inhibition of tubular secretion is one of the most important mechanisms. The inhibition of uric acid excretion and/or resorption increases due to drugs, poisoning, or endogenous metabolites. This occurs when the anion transport system is inhibited. Two important inhibitors are lactic acid and keto acids.

 

2, glomerular filtration reduction: can also increase the level of uric acid. One of these mechanisms is the reduction of the filtration rate, which is the main cause of hyperuricemia with renal insufficiency or failure. The increase in net absorption of uric acid may occur in the case of reduced capacity, which is one of the mechanisms by which diuretics induce hyperuricemia.

 

3. Increased renal tubular reabsorption: Hyperuricemia can also be caused by an increase in distal reabsorption from the site of secretion. These can be seen in the treatment of diabetes dehydration or diuretic therapy.

 

 

Third, two factors exist at the same time Many patients are at the same time the increase of uric acid production and excretion of two factors.

 

Patients with glucose 6-phosphatase deficiency, hereditary lactose intolerance. Alcohol can also retain uric acid in two ways. Excessive alcohol intake accelerates the liver's degradation of ATP and increases uric acid output. Uric acid caused by alcohol also prevents the excretion of uric acid. High purine content alcoholic beverages such as beer are also important factors.