Uric acid is the end product resulting from the gradation of purines.
Purines (adenine and guanine) are nitrogenous bases, which make up the DNA present in the nucleus of animal and plant cells.
Since our body is made up of an extremely large number of cells, which are continuously renewed, most of the purines come from endogenous synthesis, while only a small percentage derives from the foods introduced with the diet.
Uric acid circulates in the blood partly free and partly bound to transport proteins. The organ responsible for its removal is the kidney, which every day eliminates about 450 mg in the urine and another 200 mg through the digestive secretions.
Hyperuricemia occurs due to excess production and / or difficult renal elimination of uric acid.
of cells, produced following the breakdown of purines. Its concentration in the blood is the result of the balance between its production by the body and its elimination in the urine.If uric acid is produced in excess or is not eliminated sufficiently, it can accumulate in the body and cause its blood levels to rise (hyperuricaemia).
The uric acid test is used to detect elevated levels of this compound and help doctors diagnose gout. This test is also used to monitor uric acid levels over time during certain therapies and as an aid in diagnosing the causes of recurrent kidney stone formation.
uric acid is required when doctors suspect high uric acid levels or believe that joint pain or other symptoms may be due to gout.
Uricemia is measured for:
- Detect elevated levels of uric acid in the blood;
- Monitor uric acid levels when undergoing certain chemotherapy or radiotherapy treatments;
- Check gout patients who are at risk of developing kidney stones.
Hyperuricemic is defined as the person presenting a "uricemia higher than 7 mg / dl if a man and 6.5 mg / dl if a woman, after 5 days of a hypopurinic diet and without taking drugs that affect uricemia.
or with pathologies that reduce the glomerular filtration rate. Ethanol induces an increase in purine catabolism in the liver and in the formation of lactic acid, which blocks the excretion of uric acid from the renal tubules. Lead poisoning and cyclosporine (usually used in transplant patients) irreversibly damage the renal tubules, leading to uric acid retention.In many cases, the cause of the excess uric acid remains unknown.
The "high uricemia can lead to the formation of so-called" gouty tophi "in the joints, up to evident situations of gout. This last condition is characterized by an" inflammation in the joints, secondary to the precipitation of uric acid in the form of needle-like crystals of monosodium urate.
The greater the level and duration of hyperuricaemia, the greater the likelihood of developing gout, and the more severe the symptoms.
When it accumulates in the urine without being able to dissolve, then, the uric acid remains in the urinary tract. Here it can precipitate in the form of small crystals with a flattened or sometimes irregular shape, which can aggregate to form granules or stones.
These elements can cause an "obstructive uropathy.
Hyperuricemia - Main causes
Causes of uric acid or high uric acid can be different and include:
- Diet rich in foods of animal origin (red meat, game and offal);
- Kidney disorders (renal failure, stones and polycystic kidney);
- Chemotherapy treatments based on cytotoxic drugs or radiotherapy;
- Metastatic cancer;
- Multiple myeloma;
- Leukemia;
- Osteoarticular pathologies;
- Alcoholism;
- Deficiency of glucose-6-phosphate dehydrogenase (hereditary enzyme defect that affects red blood cells making them more sensitive to damage caused by oxidation);
- Gout;
- Lead poisoning;
- Obesity;
- Metabolic syndrome;
- Prolonged use of diuretics and other drugs such as levodopa, pyrazinamide and ethambutol.
