Uric acid is a substance produced in the liver derived from the metabolism of purine, a type of protein present in foods eaten daily, the more purine we ingest, the more uric acid is produced by our body.
During the evolution of species, humans lost the ability to produce an enzyme called uricase, which transforms uric acid into allantoin, a much more soluble substance in the blood. Humans have much higher uric acid levels than most other mammals. Our blood uric acid levels do not reach toxic levels just because most of us manage to eliminate excess through the kidneys.
Symptoms of elevated uric acid levels
Usual blood levels of uric acid are very close to the solubility limit, causing small increases in their concentration to cause crystallization of the latter in tissues. Uric acid is deposited in tissues in the form of sodium urate.
When there is a deposition of uric acid crystals in the joints, these cause an intense inflammatory reaction, which leads to a very painful arthritis called gout. Importantly, it takes years of elevated uric acid to develop gout disease.
Gout is classically a monoarthritis, that is, an arthritis that affects just one joint in each crisis. The joints most affected are those of the feet, mainly the first toe and knees. The clinical manifestation of gout is arthritis, that is, inflammation of a joint characterized by pain, redness, swelling and local heat.
The arthritis of the gout is so painful that some people can not even cover their feet, because the simple contact of the inflamed area with the sheet causes a great pain. There may be chills and fever, simulating an infectious picture.
The attack of the drop lasts a few days and then disappears spontaneously. The time interval between the first and second crisis may last up to two years. If left untreated, gout crises become more frequent and intense, affecting more than one joint at a time. Over the years, untreated gout leads to the formation of tophi in the joints, caused by chronic deposition of urate crystals. Tophi may be single or multiple, and may cause deformations.
Excess uric acid can also lead to the formation of kidney stones of uric acid. There is also the risk of urate deposition and tophos formation in the kidneys, causing chronic renal failure.
Gout is caused by elevated blood uric acid levels. Although, not everyone who has high uric acid develops gout. Gout is much more common in men, and occurs between 35 and 45 years. In women it usually occurs only after menopause.
The main risk factors for gout are:
- Trauma to joints.
- Long periods of fasting.
- Alcohol consumption.
- High ingestion of foods rich in purine.
- Uses of drugs that increase uric acid, such as diuretics.
Foods rich in purine (uric acid) are:
- Meats: bacon, pork, veal, goat, lamb, kidneys (liver, heart, kidney, tongue).
- Fish and seafood: salmon, sardine, trout, cod, fish eggs, caviar, seafood, oyster, shrimp.
- Birds: turkey and goose.
- Alcoholic drinks.
Foods with moderate amounts of purines or uric acid:
- Meats: cow, steer and rabbit.
- Poultry: chicken and duck.
- Seafood: lobster and crab.
- Legumes: beans, chickpeas, peas, lentils, asparagus, mushrooms, cauliflower, spinach.
Foods with low levels or no levels of a purine or uric acid:
- Yellow cheese
- Boiled egg
- Cereals such as bread, pasta, corn cake
- White rice
- Vegetables cabbage, cabbage, lettuce, chard and watercress.
- Nuts, sweets and even acid fruits.
How to diagnose gout
The diagnosis of gout is made when there is a typical clinical picture and associated with high levels of uric acid. When there is doubt about the cause of arthritis, the doctor usually punctures inflamed joint fluid for deposits of urate crystals.
How to treat it
The treatment of gout is divided into two stages treatment of crises and prophylaxis of seizures. Gout has no cure but can be controlled. During the gout crisis, treatment is performed with common anti-inflammatory drugs (NSAIDs) and/or colchicine.
Colchicine being less toxic than anti-inflammatories controls gout effectively, but it can cause unpleasant side effects, such as nausea, vomiting, and diarrhea.
Aspirin should be avoided as much as possible because, despite having an anti-inflammatory effect, it reduces the excretion of uric acid through the kidneys, once the gout crisis has ceased, treatment is focused on decreasing Of uric acid levels.
As most patients with elevated uric acid do not develop gout or renal calculi, treatment with medication is initiated if a first episode of gout crisis occurs, renal calculus. In cases of patients with asymptomatic hyperuricemia, only a change in diet is indicated, in order to avoid foods rich in purines.