Pyelonephritis
Diabetes
Hepatitis
Rheumatism
51652 October 27
IMPORTANT!
The information in this section cannot be used for self-diagnosis and self-treatment.
In case of pain or other exacerbation of the disease, diagnostic tests should be prescribed only by the attending physician. To make a diagnosis and properly prescribe treatment, you should contact your doctor. We remind you that independent interpretation of the results is unacceptable; the information below is for reference only.
Urea in the blood: indications for prescription, rules for preparing for the test, interpretation of the results and normal indicators.
Indications for the purpose of the study
Urea in the blood is synthesized in the liver from ammonia and carbon dioxide, transported by the blood to the kidneys, there it is filtered through the glomerulus, and then excreted in the urine. Urea is an osmotically active substance, so its accumulation leads to swelling of the tissues of parenchymal organs (liver, kidneys, lungs, spleen, pancreas, thyroid gland), myocardium, central nervous system, subcutaneous tissue. An increase in urea concentration several times relative to the norm, accompanied, as a rule, by a pronounced clinical syndrome of intoxication, is called uremia.
Very often, against the background of kidney disease, simultaneously with an increase in the concentration of urea in the blood, its content in the urine decreases (a decrease in kidney function leads to an increase in urea in the blood).
The study is prescribed for coronary heart disease, systemic connective tissue diseases (rheumatoid arthritis, rheumatism, systemic scleroderma, etc.), arterial hypertension (regardless of the duration of its existence), when detecting abnormalities in a general urine test during a screening study, liver disease accompanied by dysfunction (hepatitis, cirrhosis), if inflammatory or infectious diseases of the kidneys are suspected, diseases of the gastrointestinal tract, as well as before and during drug therapy, before hospitalization of the patient due to an acute illness, after dialysis sessions for evaluation their effectiveness.
The concentration of urea in the blood characterizes:
- the state of the excretory function of the kidneys, that is, their ability to excrete substances unnecessary to the body with urine;
- the condition of muscle tissue (as a result of the breakdown of protein in the muscles, urea is formed);
- liver function, where ammonia is converted to urea.
Why might urea be elevated?
To determine the level of urea in the blood, a laboratory method called a biochemical blood test is used. It involves taking material from a vein. For each age category of patients there is its own norm for urea content in the blood:
- in newborns from 1.7 to 5;
- in children of the first year of life from 1.4 to 5.4;
- from one to 15 years old can have 1.8-6.7;
- women over 18 years old - from 2 to 6.7;
- men over 18 years old - from 2.8 to 8.
Several factors influence the urea content. One of which is the level of amino acids in the body, since ammonia is formed from them during metabolism, which becomes one of the components of urea. On the other hand, with a sufficient amount of amino acids, the diseased liver will not be able to synthesize urea, which will be the reason for the detection of its negligible amount. The third important factor is the performance of the kidneys, which must, by filtering the blood, extract urea from it and send it out of the body with urine.
If we exclude all possible pathologies, then we can say that the following factors not related to the disease can increase the level of urea in the blood:
- on the eve of the collection of material, severe emotional stress was experienced;
- the patient had to buy and take a drug from the list: Tetracycline, Euthyrox, Neomycin, Lasix, any drug from the group of corticosteroids or sulfonamides, anabolic steroids, steroids, salicylates;
- the patient fasted for a long time or, on the contrary, ate a lot of protein foods;
- the patient on the eve of the delivery of the material or daily subjected the body to heavy physical activity.
When a doctor tries to determine the quality of kidney function, the presence of urea in the blood may indicate:
- blockage of the urinary ducts;
- chronic. renal failure;
- glomerulonephritis;
- pyelonephritis;
- dehydration, which could be preceded by myocardial infarction, shock or heart failure.
Separately, we should highlight the reasons why urea is formed in the human body in huge quantities:
- prostate neoplasms;
- burn disease;
- severe intestinal infections;
- hematological diseases;
- state of shock.
To accurately determine the patient’s condition, it is necessary to conduct several laboratory tests in a row to see the picture in dynamics; in addition, it is necessary to measure the amount of urea in the urine in order to be able to compare this indicator with blood data.
Urea: norm and pathology
The test results are interpreted according to the patient's age and gender. Lifestyle, a number of physiological indicators and other factors are also taken into account. Only a doctor can correctly evaluate the test results.
The test is used as part of a comprehensive laboratory diagnosis of kidney and liver diseases. It must be taken into account that in some cases an increase in indicators is not a sign of pathology. For example, an increase in urea levels can be caused by eating too much protein or significant physical activity (after heavy physical work, intense sports training). A decrease in indicators is typical for pregnant women.
A significant increase in the level of this substance may indicate renal failure or disruption of the excretory system. Indicators below the reference values indicate liver pathologies and impaired protein absorption. Normally, urea levels in adult patients should be in the range of 2.1-7.1 mmol/l. For children and patients over 60 years of age, their own reference values have been established.
How to take a urea test correctly
You need to prepare for the analysis so as not to receive distorted data. First of all, you need to remember that blood is donated strictly on an empty stomach. In addition, since urea production is affected by the breakdown of muscle fibers, it is important to avoid physical activity on the eve of the test. If you can’t get to the laboratory without excessive physical activity, you need to arrive at the door of the office no later than half an hour before the appointed time in order to have time to calm down and put your nervous system in order.
If the patient is taking any medications, it is better to postpone the morning dose until the blood has already been donated. Immediately before the donation, you should not do massages, biopsies, or x-rays, especially those using contrast.
Causes of increased uric acid
High uric acid levels can occur with the following:
- Excess weight.
- Excessive eating.
- Low fluid consumption.
- Alcohol abuse.
- Sedentary lifestyle.
The main diseases that can be caused by high levels of uric acid are:
- Joint diseases.
- High blood pressure.
- Cardiovascular diseases.
- Diabetes.
- Blood diseases, including leukemia.
- Infectious diseases.
- Skin pathologies.
- Intoxication of the body.
- Malignant neoplasms.
What dangers do these substances pose?
An increase in urea and uric acid in the blood serum can result in the development of various dangerous pathologies for a person. Most often, patients consult a doctor at a time when pathological changes are already occurring in the body.
This occurs because in the first stages of diseases that cause the accumulation of urea and uric acid, there are no specific symptoms.
The patient may experience general weakness, increased fatigue or headaches. People most often attribute all these ailments to overwork and do not consult a doctor. However, over time, when the concentration of these substances reaches high values, the body begins to malfunction, and serious symptoms of the disease arise. At this stage, the disease is already progressing, and all human organs are gradually subject to deviations. The result is severe diseases of all systems, intoxication of the body, and in especially severe cases, death cannot be ruled out.
Treatment of abnormalities
Now that it has become clear that urea and uric acid are two completely different substances, although similar in some ways, it should be noted that the treatment of abnormalities cannot be the same. Treatment should be prescribed by a doctor, taking into account the root cause of the deviation. It is generally accepted that an increase in uric acid is much more dangerous for the body, but the damage from an increase in urea cannot be underestimated. Each of the deviations carries a threat to humans. For this reason, self-medication is unacceptable. Only a doctor can prescribe adequate therapy for you.
Diagnostics
Both substances under consideration belong to the group of residual nitrogen compounds. Their concentration in the blood is determined during biochemical analysis. In this case, urea on average makes up 45% of the total residual nitrogen, and uric acid only about 20%. In addition to these indicators, experts also evaluate the content of other substances belonging to the group of residual nitrogen, including creatinine, amino acids, ammonium, creatine, etc.
In total, this fraction includes more than 15 substances, but these are the most significant for diagnosis.
In order for the analysis of residual nitrogen components to be as accurate as possible, you need to follow the basic rules for donating blood. The most important of them is taking the test on an empty stomach. It is also necessary to avoid taking alcohol and any medications a few days before the test.
Only a specialist should decipher the analysis. Only a doctor will be able to correctly evaluate the results of your analysis and make a preliminary diagnosis, which will later be confirmed or refuted by additional diagnostics. Quantitative determination of the components of residual nitrogen is not a means of accurate diagnosis, but is only a reason to suspect a disease.
Prevention
Prevention of deviations of substances in the residual nitrogen fraction consists primarily of maintaining a healthy lifestyle. If we look at the statistics, we can see that initially deviations develop against the background of poor nutrition and a sedentary lifestyle. The situation is further aggravated by weak immunity and the emergence of chronic diseases.
It is especially important to monitor urea and uric acid levels in children. Deviations in these indicators can result in the development of severe and intractable pathologies for them. It is for this reason that children need to have blood biochemistry done at least once a year.
Every person should understand that any blood component is an indicator of the health of internal organs and systems. Never neglect donating blood for analysis, because it is this substance of our body that first of all reacts to the presence of a disease. In this case, indicators deviate even before the appearance of symptoms of the disease. Monitoring the level of urea and uric acid will allow you to promptly identify abnormalities and receive adequate treatment before dangerous pathologies develop.
At what urea levels should you go to the doctor?
Any deviation from normal levels of nitrogen-containing substances in the blood is a reason to consult a doctor. A full consultation can be carried out by a therapist or nephrologist.
A specialized doctor conducts a full examination of the patient, finds out the presence of complaints, and studies the results of previous studies. For the purpose of clarification, additional tests and hardware diagnostics may be prescribed. The data from all examinations make it possible to establish the root cause of biochemical disturbances in the blood formula, a disorder in the mechanism of breakdown of nitrogenous substances and subsequent removal from the body through the excretory system.
