Diagnosis
The diagnosis of hyperuricemia is primarily based on the laboratory value. There are other diagnostic tests to clarify the cause. If a high uric acid level is suspected, the uric acid level in blood serum is determined.
Values above 6.5 mg/dl are considered to be above the normal range. Furthermore, the excretion of the uric acid concentration in the urine can be measured. This plays an important role in differentiating between primary, i.e. hereditary, uremia and secondary hyperuricemia.
If there is a genetic cause, the uric acid excretion via the kidney is limited in most cases. In about one percent of cases, it is an enzyme defect that is associated with an overproduction of uric acid. The determination of uric acid clearance distinguishes between overproduction and reduced excretion.
For this purpose, in addition to the uric acid concentration in the serum, the concentration in the 24-hour collective urine is also measured. The ratio of uric acid to creatinine serves the same purpose, but is less accurate. Symptomatic hyperuricemia in the form of unspecific joint complaints is treated by means of a joint puncture. For this, synovial fluid is taken with a needle and examined for uric acid crystals. The uric acid level is not necessarily elevated in acute attacks of gout.
Therapy
As long as hyperuricemia does not cause any symptoms, a conservative therapy recommendation is usually sufficient. Measures include low-purine, preferably low-meat diet, low alcohol consumption and weight loss in overweight patients. In addition, the daily fluid intake should be at least two liters.
This applies up to a uric acid level of 9 to 10 mg/dl. If the concentration is above this level, or if the first clinical symptoms are observed, medication measures are initiated. A preferably permanent reduction of the serum uric acid concentration to 5.0 to 5.5 mg/dl is targeted.
In the context of secondary hyperuricemia, the underlying disease should first be treated. Uricostatics and uricosurics are also used. Febuxostat and allopurinol inhibit the formation of uric acid.
Benzbromarone acts on the kidney and thus reduces the reabsorption of uric acid. Uricostatics as well as uricosurics are used in the therapy of gout. If the uric acid level is elevated, some foods should be avoided.
This also applies if no manifest symptoms are present. Purine-rich foods are broken down in the body to uric acid and contribute to a further increase in its value. A high proportion of purine is found above all in meat and intestines.
This includes in particular pork, goose and beef.Some types of fish such as trout, herring and sardines also have a high concentration of purine. Some vegetables like peas, cabbage and beans should be consumed in small amounts. A significantly reduced consumption of alcohol also plays an important role in lowering uric acid levels. It is not necessary to avoid products with a high protein content such as dairy products. Fruit and most vegetables can also be consumed without hesitation.
