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Urate in urine
Last reviewed: 23.04.2024
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The constant renewal of nucleic acids and proteins in the cells of the body occurs by the metabolism of purine nucleotides and the exchange of nitrogen-containing protein (purine) bases. At the final stage of this biochemical process, 2,6,8-trioxipurine is formed - uric acid, the major part of which is excreted by the kidneys. Urine salts - urate - under certain conditions can accumulate in the kidneys and bladder, and then the doctors determine the urate in the urine - in the form of fine particles, like yellowish granules.
The causes of urate in the urine
When they say that the key reasons for the appearance of urate in the urine lie in the excessive use of purines with food (that is, proteins of animal origin), then only the tip of the "iceberg" of metabolism is noted. It is known that nutritional purines are involved in the synthesis of tissue nucleic acids only slightly, but, nevertheless, their excess quantity increases the risk of urates.
The lion's share of exogenous purine bases (amino and oxypurines) is converted to 2,6-dioxipurine (hypoxanthine), then to xanthine and finally oxidized to uric acid. At different stages of its formation pathogenesis can be associated with inadequate activity of enzymes.
Thus, the inactivation of alosteric enzymes exchanging purine nucleotides (FDDF synthase, GGFT, etc.) leads to an increase in the level of uric acid in the blood plasma (hyperuricemia) and increased excretion of urate in urine (uraturia).
The last stage of uric acid formation is provided by xanthine oxidase, which is synthesized in the cells of the intestine and liver, and which can also have problems in the form of hereditary xanthinuria.
The causes of urate in the urine can be caused by defects in genes responsible for the release of uric acid by the kidneys - SLC2A9, SLC17A1, SLC22A11, SLC22A12, ABCG2, LRRC16A, etc.
In addition, it is necessary to take into account the factor of functional disorders of the kidneys, because urine, from which metabolites and excess salts are excreted, is formed in them - as a result of glomerular filtration of blood plasma and reverse absorption of water and the bulk of the substances needed by the body. Violations of these biochemical processes are also capable of causing the appearance of uric acid salts in urine.
The high concentration of poorly soluble uric acid and urate in the urine is not a medical indication, but is associated with various diseases and pathologies. Their code for ICD 10 is E79.0-E79.9 (impaired metabolism of purines and pyrimidines).
One way or another, pyelonephritis and kidney tuberculosis are related to these disorders; renal acidosis in diabetes and alcoholism; fatty infiltration of the kidneys; prolonged fasting or rapid loss of body weight; Cohn's syndrome (primary hyperaldosteronism); loss of fluid with prolonged vomiting and diarrhea; drop in the level of potassium in the blood; oncopathology of hematological character (leukemia, lymphoma); taking certain medicines (for example, ascorbic acid, antibiotics and thiazide diuretics).
Consequences of the violation of purine metabolism are manifested by chronic and acute renal failure, and with increased acidity of urine (pH less than 5) urates in the urine precipitate in the tubules of the kidneys followed by crystallization, formation of urate sand and stones (stones) and the development of urolithiasis - one of the varieties of urolithiasis disease. Crystals of urate salts (most often - calcium) can also settle in articular tissues, causing inflammation of the joints and periarticular structures.
Symptoms of urate in the urine
Nephrologists emphasize the fact that urate symptoms in the urine are absent, and the person does not feel anything when the urine contains uric acid salts.
The first signs of the pathology of purine metabolism can appear only after the acidity of urine is increased, which promotes the formation of crystals. And only on the analysis of urine it is possible to reveal infringement which can lead to serious problems with kidneys.
Urates in urine during pregnancy, whose appearance is most often associated with either vomiting or dehydration in case of early toxicosis, or with increased consumption of protein foods, also show no effect.
In the case of xanthinuria - a sufficient rare pathology of uric acid metabolism - xanthine crystals can settle in muscle tissues and cause pain during exercise.
Urate in the urine of a child, more precisely, their high concentration, leave on the diapers traces of pink and orange. But with the genetically conditioned Lesch-Nihan syndrome (code on ICD 10-E79.1), it does not reach urates, although the serum content of uric acid (due to the complete blockage of one of the purine metabolism enzymes) is simply off scale. As a result, urate concretes are formed in the urinary tract, and granular accumulations of crystallized uric acid (tofusi) form beneath the skin. A child with this syndrome lags behind in the development of motor, psyche and mental abilities from an early age; Spasticity, involuntary movements and manifestations of aggression are noted (also in relation to oneself: the child bites fingers, tongue and lips). If the functional disruption of the kidneys is not treated, then the prognosis is a fatal outcome before the child reaches 10 years of age.
Diagnosis of urate in the urine
The most accessible diagnosis of urate in the urine is a laboratory study of the composition of urine.
Required tests: blood - for acidity and uric acid; urine - the pH level and the content of uric acid (or xanthine) and its salts (Na, Ca, K, Mg). A characteristic feature of the presence of crystallized uric acid in urine is a yellow precipitate; urate urine clouded, and the sediment has a more intense color - to the reddish-brown.
Nephrologists and urologists also perform instrumental diagnostics - ultrasound (ultrasound) of the kidneys, in which urate sand can be found in them.
A differential diagnosis is aimed at accurately determining the composition of salts in urine, since in addition to urates, oxalates (oxalate calcium), as well as phosphates (calcium phosphate or magnesium) can be present in it.
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Urate treatment in urine
The main method, which is recommended in clinical practice is urate treatment in urine, is diet therapy.
Diet with urate in the urine - number 6 in Pevzner, vegetable-lactic, with a strict restriction of the use of animal proteins (per day - not more than one gram of meat in boiled form for each kilogram of weight). In addition, red meat and concentrated broths are excluded; meat by-products, lard and sausage products; fish, eggs, legumes, mushrooms; all sharp, salty and sour; chocolate, cocoa and coffee. It is very important to maximally reduce the daily amount of salt - up to 7-8 g.
In the diet should be dairy products, vegetables, cereals, fruits and berries (not acidic); daily volume of consumed liquid - not less than 2.5 liters; To reduce urine pH, table alkaline mineral water is useful.
Drugs, most commonly used with urate in the urine, include:
- vitamins A, B6, E
- orotic acid in the form of tablets Potassium orotate (increases the synthesis of proteins, increases diuresis); It is applied inside by 0.25-0.5 g to three times a day (60 minutes before meals). The dose for children is 10-20 mg per kilogram of body weight.
- Benzobromarone (Normurat, Azabromaron, Khipurik, Uriconorm, etc.) - inhibits the absorption of uric acid in the renal tubules and increases its excretion. Dose - 50-100 mg once a day (during meals).
- K-Na hydrogen citrate (Blamaren, Soluran) - maintains a neutral pH of the urine; The dosage is determined individually based on the results of the tests.
- Allopurinol (Allogexal, Milurit, Ziloprim) - by blocking the enzyme xanthine oxidase reduces the synthesis of uric acid and helps to break down the urate; It is used for hyperuricemia and Lesha-Nihan syndrome.
Preparation Etamid (Etebenezid) reduces the content of uric acid in the blood, delays its reabsorption in the kidneys and promotes excretion from the body. Usage: inside by 0.35 g 3-4 times a day (after eating). Should be taken within 12 days, 5 days break, and another week to take.
Among the drugs that offers for the treatment of urates in the urine of homeopathy, drugs based on the seed extract of the poisonous colchicum autumnale (Colchicum autumnale) are noted.
Alternative treatment of this pathology involves herbal medicine, in particular: diuretic broth sporey (tablespoon 250 ml boiling water, take 1/3 cup three times a day) and infusion of the roots of the madder dyeing (in the same dosage).
The best prevention of the appearance of urate in the urine - in order to prevent complications of violations of protein metabolism and uric acid metabolism - is the proper nutrition with a decrease in the proportion of meat products in the diet.