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Urine diathesis
Last reviewed: 23.04.2024
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Hyperuricosuria, hyperuricuria, urate or urate acid diathesis is defined as a congenital predisposition of the organism to increased excretion of the main end product of purine metabolism (protein metabolism) - uric acid. Excess of this acid leads to its crystallization and the formation of salts that do not dissolve, but form in the kidney and urinary bladder concrements - uric acid (urate) stones.
Causes of the urine acid diathesis
Previously, urine acid diathesis was classified as idiopathic states and its pathogenesis was indirectly associated only with the predominance of protein foods of animal origin containing purines in the diet. As a result of biochemical transformation of purine bases in the human body, 0.75-0.8 g of purine-2,6,8-trione - uric acid, which is excreted in the urine, is released per day.
To date, the causes of urine acid diathesis clinical urology sees in the endogenous overproduction of uric acid, that is, in violations of nitrogen metabolism. According to statistics, urine acid diathesis in adults has this etiology in almost every third case.
It was established that the predisposition to abnormalities of protein metabolism is of a genetic nature and is inherited. Often this has the form of xantynuria, that is, a deficiency of the xanthine oxidase enzyme, which is involved in the formation of uric acid from xanthine and hypoxanthine.
In addition to the excess concentration of uric acid, urine acidity plays an important role in the pathogenesis of urine acid diathesis, since at pH below 5.5 almost 100% of uric acid exists in a non-dissociated form. This means that uric acid does not dissolve in acidic urine and forms crystals. And the mechanism of formation of urate crystals researchers see in combining several main factors: high acidity of urine, hyperuric urine, small volume of urine and lack of extracellular fluid in the body. Thus, one or more of these factors are found in patients with uric acid stones (uric acid nephrolithiasis). Patients with gouty symptoms of urinary diathesis tend to have urine pH <5,5 and elevated levels of uric acid in the blood serum, and in urine it may be close to normal.
The causes of urine acid diathesis may also be related to other metabolic processes in the body. Recent studies have revealed a relationship with resistance (insensitivity) to insulin in patients with normal uric acid and urine acidity. Thus, many patients with idiopathic stones of uric acid may have problems with insulin sensitivity ( diabetes insipidus ), which leads to an increase in urine concentration, insufficient urine volume and an increase in the content of uric acid and ammonium.
In addition to excess protein food, obesity, intake of vitamins (especially B3) and fluid loss due to vomiting in the first months of gestation, one of the causes of urinary acid diathesis in pregnancy is excessive activity of the antidiuretic hormone of the hypothalamus vasopressin regulating the process of excretion of the kidneys . Also, in pregnant women there is an increased production of the adrenal hormone aldosterone, which increases the volume of circulating blood (which is necessary for the child to carry), but the excretion of potassium from the body increases, which leads to an increase in the acidity of urine, edema and increased blood pressure.
Urine diathesis in children can be associated with damage to the hypothalamus (which produces vasopressin ), which leads to many problems, including - the violation of glomerular filtration of the kidneys and increased levels of uric acid. Urine diathesis in newborns is possible because of the rare congenital Lesch-Nyhan syndrome, in which the male infants have an X chromosomal deficiency of the phosphorylbosyl transferase enzyme, which provides the most important reaction of the purine cycle-the purification of purines. If this enzyme is not enough, the synthesis of endogenous purines rises sharply and turns a child into a disabled child.
[Symptoms of the urine acid diathesis
Urologists believe that the first signs of urine acid diathesis appear in the increased formation of uric acid crystals in the urine. Although this requires that the acidity of urine was above the physiological norm of pH 6.5-7.
Urine is acidic in nature, but while the degree of acidity is low enough, there is no discomfort in humans. When the acidity of urine increases (pH decreases), urine acid diathesis in adults can manifest as a burning sensation when urinating: this is how the mucous membrane of the bladder and urethra reacts to the abnormal urine pH. In addition, the color of the acidified urine is darker, and the smell is sharper.
Symptoms of urine acid diathesis with a high level of acidity of blood can also manifest in a sense of fatigue, constipation, loss or weight gain, increased blood pressure, heart problems of muscle weakness, chronic kidney disease. A high level of uric acid in the blood (with its insufficient filtration by the kidneys) can lead to bouts of gout. However, it should be borne in mind that not everyone who has hyperuricosuria has gout, and not everyone with gout has an elevated uric acid content (gout and urine acid diathesis are not the same).
The urine acid diathesis in children is manifested in the fact that the urine test results in the presence of crystals or salts of uric acid in it, as well as the increased acidity of urine. A very high level of uric acid is also observed in blood plasma. By the way, this may indicate that the child has problems with the thyroid gland - hypothyroidism.
Pediatricians distinguish such key symptoms of urinary diathesis as breath with the smell of acetone; causeless irritability; nausea and vomiting; poor appetite and weight loss, as well as pain - head, joint and kidney.
Complications and consequences
The effects of urine acid diathesis - the formation of urate (urinary) stones. In 90% of cases in the concrements, calcium or sodium salts are detected, in 15-20% of patients calcium calculi in the kidneys are formed; about the same picture and in people with gout. As a complication of urate diathesis, experts call the chronic form of urolithiasis and kidney failure. Severe hyperuricosuria can lead to acute nephropathy: urates settle in the renal tubules with their subsequent obstruction and severe azotemia.
Diagnostics of the urine acid diathesis
Diagnosis of urinary diathesis is carried out by a urologist or nephrologist who prescribes the following tests:
- biochemical blood test with determination of uric acid level;
- blood test for pH (pH);
- general analysis of urine;
- daily urine analysis (for determination of diuresis, pH, uric acid, calcium, sodium, citrate, phosphorus, xanthine and creatinine).
Instrumental diagnosis of urinary acid diathesis is ultrasound of the kidneys, bladder and urinary tracts, in which urate sand can be found in them.
Problems with the violation of the general acid-base state of the body (metabolic acidosis) revealed during the examination should be solved by differential diagnosis - by examining the lungs and the liver, as well as additional tests, for example, arterial blood analysis for carbon dioxide stress, buffer bases and standard bicarbonates; a blood test for corticosteroids ( aldosterone ), and others.
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Treatment of the urine acid diathesis
It is generally considered the treatment of uric acid diathesis by the appointment of a diet with protein restriction, high fluid intake (up to two liters per day) and a decrease in salt (ie sodium). Low sodium intake reduces its removal from the body, reduces the formation of monosodium urates, and also helps to reduce calcium excretion in the urine.
Recommended diet for urine acid diathesis - №6, for more details see - diet with increased uric acid.
The most important drugs used to reduce uric acid in the urine are those that alkalinize urine to pH 6.5-7. This is potassium citrate (Urozit, Kalinor, Polyciter-K), which inhibits the crystallization of calcium oxalate and reduces the acidity of urine. And also tablets Soluran (Blemaren), containing a mixture of potassium citrates and citrate, which make the urine more alkaline.
The drug Allopurinol (Zyloprim) inhibits the enzyme xanthine oxidase and thereby reduces the conversion of hypoxanthine and xanthine to uric acid. The initial dosage is 300 mg per day.
Alternative treatment is carried out with the help of diuretic broths and infusions, that is, this traditional herbal treatment. For their preparation, such medicinal plants as the bearberry, the mountain herring, the elephant, the wheatgrass (rhizome), the birch buds, the cowberry leaf, the hips, etc. Are prepared. The broths are prepared in the standard way: a tablespoon of dry raw material 250-300 ml of boiling water is poured, brought to a boil and put on 40-45 minutes for insisting. All infusion is taken for a dose of 100 ml at a time. It should be borne in mind that children and pregnant diuretics are appointed with caution - only after the delivery of a 24-hour urine test.
Experts in the arsenal of preparations provided homeopathy note Causticum, Kalium carbonicum, Lycopodium.
Forecast
With proper nutrition and careful attitude to your health, the prognosis is positive. And remember: uric acid diathesis should not go into kidney failure, and in this you can only help medicine.