Through the analysis of a blood sample, numerous data can be known to evaluate the state of health. This blood test is generally composed of two sections. One is the hemogram, which refers to blood cells, and the other is biochemistry, in which the concentration of chemicals in the blood such as hormones, minerals, and urea is assessed.
Although the values of the blood count are the most requested by the doctor, the amount in the blood flow of the chemical elements also provides essential information about the condition of the body. If you have questions about uremia in a blood test, in this FastlyHealarticle, you can find complete details about its nature, average values , and what high urea means.
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Uremia is a blood test: What is it?
In a blood test, uremia refers to the amount of urea found in the blood. Sometimes it is mentioned that urea is the same as urea nitrogen. Still, the latter is the proportion of nitrogen part of urea, which is approximately 50% of its composition. Uremia is also known as a uremic syndrome, and it is a clinical state in which the concentration of urea in the bloodstream is high as a consequence of inefficiency in its elimination.
Primarily a blood urea test is performed to have an overview of the functioning of the kidneys, so it is requested to know if there is any alteration in these organs or to tell if a particular disease is controlled. However, it is not about a diagnostic analysis; it does not indicate the cause of the alteration. It must complement other tests that the doctor considers appropriate, such as creatinine or urine samples.
How is urea made in the body?
For the body to synthesize urea, proteins go through a degradation cycle. Specific enzymes are separated into amino acids, which release a nitrogen component that is highly toxic to the body, so other enzymes do so. They bind to other elements to form urea, although it is still a poisonous substance, and it is quickly eliminated, primarily through urine and feces, and sweat.
This degradation process occurs in the liver, and when urea is produced, it is released into the bloodstream towards the kidneys. Under normal conditions, these organs are responsible for purifying the blood and take as much area to be discarded. Still, when something alters this function, the kidneys cannot retain urea, and it accumulates in the blood, leading to uremia.
Urea: normal values
- In men: the average value of urea in the blood for men is between 18 to 45 mg/dl
- In women: average values can be between 15 to 42 mg/dl.
On the other hand, in adults, these values are usually slightly higher and are still considered within the normal range, and in children between 1 to 13 years of age, it is established as usual between 11 to 36 mg/dl. However, the result of the blood test must be determined by a specialist since the limit values may vary from one laboratory to another.
The severity of uremia in a blood test depends on how high its concentration is; if it is between 50 to 100 mg/dl, it is related to excessively high levels, but if treatment is given in time, it is possible to control the condition and avoid severe damage. On the other hand, if the test result is more significant than 100 mg/dl, it is considered a critical level and compromises the person’s health, requiring immediate attention.
Uremia: signs and symptoms
When the urea in the blood is slightly higher than usual, it does not usually show symptoms. Still, as the accumulation of said nitrogenous substance progresses, sure signs become evident, and that is when it is considered that there is uremia or uremic syndrome. Because this disorder can cause severe damage to the body and is potentially fatal, knowing how to identify the symptoms increases the possibility of being treated in time. Among them, the following stand out:
- Muscular weakness.
- Pallor.
- Nausea and vomiting
- Diarrhea.
- Weightloss.
- Fast heartbeat
- Involuntary muscle contractions in the hands.
- Bad breath and a bitter or metallic taste in the mouth.
- Acute and painful lesions in the mouth.
- Subcutaneous bleeding in the form of purple or red spots on the skin.
- Decrease in body temperature
- Temporary and complete loss of movement and sensation of the body.
High blood urea: causes
The leading cause of uremia in a blood test is the existence of a kidney problem or failure that was not controlled in the time since if the functions of the kidneys are altered by some disorder, they can prevent the proper filtration of urea or limit the elimination of this substance, causing it to continue traveling in the bloodstream and accumulate in different parts of the body. Among the most common kidney diseases are:
- The kidney stones
- Obstruction of the excretory pathways
- Diabetic nephropathy
- Nephrotic syndrome
- Chronic renal failure
However, a high urea value in a blood test can also have another origin, although it is not so common that they tend to develop the accumulation of said substance to dangerous levels. These alterations include an increase in the formation of urea in the liver due to:
- Follow a high protein diet
- be hypertensive
- Suffering from gastrointestinal bleeding
- Liver diseases such as cirrhosis.
Also, dehydration is another reason why the amount of urea in the blood rises, because there is not the necessary fluid to eliminate waste substances from the body.
This article is merely informative, at FastlyHeal .com we do not have the power to prescribe medical treatments or make any diagnosis. We invite you to see a doctor in the case of presenting any type of condition or discomfort.
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I am a Surgeon with a diploma in comprehensive ultrasound and surgical care residency, an area I am specializing in. During the exercise of my profession, I have realized the need for patients to know the diseases they suffer, and I can tell you that a large part of their complications is due to a lack of information. Being a health web writer allows me to transmit my experience, without borders, to all those readers eager for knowledge, educate them in the prevention of diseases and promote a healthy lifestyle.