uric acid

and Eva Rudolf-Müller, doctor

Eva Rudolf-Müller is a freelance writer in the medical team. She studied human medicine and newspaper sciences and has repeatedly worked in both areas - as a doctor in the clinic, as a reviewer, and as a medical journalist for various specialist journals. She is currently working in online journalism, where a wide range of medicine is offered to everyone.

More about the experts All content is checked by medical journalists.

Uric acid is a breakdown product of purines. These are the building blocks of nucleic acids that contain the genetic information of an organism. The purine bases are called adenine and guanine. Read here how uric acid is produced in the body, which diseases change uric acid levels and how diet influences uric acid levels.

What is uric acid?

Uric acid is produced when what are known as purines are broken down. These are the building blocks of DNA or RNA that contain the genetic information. In a healthy body, there is a balance between making and breaking down purines. However, various illnesses, certain eating habits and the use of certain medications can upset this balance. This changes the uric acid level.

The metabolism of uric acid in the body

As part of the purine breakdown, the body produces around one gram of uric acid per day. Most of it is bound to proteins in the blood. Since it is a metabolic end product that the body does not need, the uric acid is excreted. 80 percent of this happens through the kidneys (with the urine); the rest is excreted in the stool through the intestines.

An elevated uric acid level is known as hyperuricemia. If the uric acid level is too low, it is called hypouricemia.

Uric Acid & Diet

Our diet has a major influence on the blood concentration of uric acid. Foods that contain a lot of purines (uric acid is produced when they are broken down) are, for example:

Meat, especially offal and skin of fish and poultry
Fish, especially sardines, trout, tuna, salmon and sprat
Compressed yeast

When is uric acid determined?

The doctor determines the uric acid to detect what is known as primary hyperuricemia. It is a congenital, genetic disease that is popularly known as gout. The doctor will also measure uric acid regularly during check-ups as the disease progresses.

The uric acid levels are also determined if there is a suspicion of diseases that have an influence on the uric acid level. For example:

chronic kidney disease
Overactive parathyroid gland
alcoholism
Dehydration
Haemolytic anemia (anemia caused by the breakdown of red blood cells)
leukemia
Diabetes mellitus
Lipid metabolism disorders

The doctor can determine the uric acid concentration both in the blood (serum or blood plasma) and in the urine.

Can I also measure uric acid at home?

For patients with a chronic disease, it is sometimes advisable to measure uric acid regularly at home. For this there are small, portable measuring devices, similar to the commercially available measuring devices for determining blood sugar. Sometimes such a uric acid meter is already integrated into a blood glucose meter.

In kidney disease, uric acid excretion can also be measured with a uric acid test strip. You simply hold this in the collected urine. Depending on the uric acid concentration, the test field on the test strip changes color accordingly. The result can be read from a reference color table.

Uric acid values: table with normal values

The normal levels of uric acid in the blood depend on age and gender. Please refer to the following uric acid table to find out how high these values are:

age	Female	masculine
up to 1 month	1.0-4.6 mg / dl	1.0-4.6 mg / dl
1 to 12 months	1.1-5.6 mg / dl	1.1-5.6 mg / dl
1 to 5 years	1.8-5.6 mg / dl	1.8-5.6 mg / dl
6 to 11 years	1.8-5.9 mg / dl	1.8-5.9 mg / dl
12 to 14 years	2.2 - 6.4 mg / dl	3.1 - 7.0 mg / dl
15 to 17 years	2.4 - 6.6 mg / dl	2.1 - 7.6 mg / dl
from 18 years	2.5 - 6.5 mg / dl	3.0 - 6.9 mg / dl

When is the uric acid level decreased?

Overdosing on uric acid lowering drugs is one of the most common reasons for low uric acid levels. Some other drugs, such as estrogen preparations, can also cause low uric acid levels in laboratory tests.

The congenital disease xanthinuria also means that uric acid is too low. It is a disruption of the enzyme xanthine oxidase, which plays an important role in the breakdown of purines.

When is the uric acid level increased?

A concentration of six (women) or seven (men) milligrams per deciliter (mg / dl) blood is called hyperuricemia. With this increased concentration of uric acid in the blood, it crystallizes and is deposited in joints, tendon sheaths, bursae, in the subcutaneous tissue and in the medulla of the kidneys.

Uric acid increased

If you want to find out more about the causes and consequences of hyperuricemia in the body, read the article Uric acid increased.

In addition to the genetic, congenital primary hyperuricemia (gout), the following diseases or metabolic situations lead to an increased uric acid level:

severe renal impairment (renal insufficiency)
increased breakdown of protein in the body, for example in the case of malnutrition, fasting, zero diet
Overactive thyroid or parathyroid gland (hyperthyroidism, hyperparathyroidism)
Deficiency in the enzyme glucose-6-phosphatase
Diseases with an excessive increase in blood cells (myeloproliferative diseases)
EPH gestosis (various pregnancy diseases with high blood pressure, for example preeclampsia)
Acromegaly (excess of growth hormones)
Chemotherapy and radiation therapy
Poisoning, for example with lead

Taking various medications can also increase uric acid levels. These include beta blockers, dehydrating agents (such as furosemide) and special antibiotics (such as ethambutol for tuberculosis).

What to do if the uric acid level changes?

There is no special therapy for hypouricemia associated with the metabolic disease xanthinuria. Those affected have to drink a lot and have a low-purine diet.

Hyperuricemia should be treated urgently. Otherwise the deposited uric acid crystals can trigger a painful inflammatory reaction.

Since the body absorbs purines through food, an elevated uric acid level can be favorably influenced by a low-purine diet. In addition to a change in diet, normalization of body weight and abstaining from alcohol are recommended. If these basic measures are not enough, the doctor may prescribe drugs that lower uric acid.