Uremia is the poisoning of the blood with urinary substances such as urea, creatinine and uric acid. This type of urinary intoxication occurs primarily in connection with kidney damage and so-called terminal renal insufficiency, as well as acute kidney failure.
Uremia leads to increasing intoxication of the blood with urinary substances @ Pepermpron /AdobeStock
Uremia can be chronic on the one hand and acute on the other. In acute uraemia, there is predominantly extensive oedema formation, as no more fluid can be excreted via the dysfunctional kidneys. This increases the pressure in the blood vessels, which is why patients with acute uraemia often suffer from high blood pressure.
Chronic uraemia, in turn, is caused by chronic kidney damage, as a result of which kidney function continues to decline, causing urinary substances to accumulate more and more in the blood.
Uremia manifests itself in a wide variety of symptoms and affects practically the entire human organism. As uraemia is usually the result of renal insufficiency, many of its symptoms overlap with those of kidney damage.
In the nervous system, urinary intoxication results in
- pronounced drowsiness (somnolence),
- disorientation,
- amnesia,
- cerebral edema or
- sensory disturbances due to polyneuropathy.
Symptoms occur in the digestive system such as
Ascites is a pathological accumulation of fluid in the abdominal cavity @ donikz /AdobeStock
In the blood, the toxins also lead to malfunctions of the thrombocytes and blood clotting as well as to a disruption of the immune system by damaging the necessary white blood cells.
In the cardiovascular system, high blood pressure (hypertension), uraemic inflammation of the heart and cardiac insufficiency are particularly noticeable in uraemia.
The respiratory system is also damaged in close connection with the cardiovascular system. This results in the lungs
- edema formation (fluid accumulation),
- inflammatory reactions and
- the characteristic "Kussmaul respiration", usually as a result of hyperacidity of the blood (acidosis).
However, these are all symptoms that usually develop invisibly inside the body. In addition to the Kussmaul respiration due to acidosis, uremia also leads to characteristic skin symptoms that indicate urinary intoxication. These include, for example
- pronounced itching (pruritus),
- a gray-yellow skin coloration ("café-au-lait spots") and
- general pigmentation disorders.
Uremia is diagnosed in connection with renal insufficiency on the basis of blood values. As with the blood count, a tube of blood is taken and analyzed in the laboratory. The retention values for urea, creatinine and uric acid are of particular interest in uremia. If these values are elevated in the blood, doctors speak of uremia - an accumulation of urinary substances in the blood.
Uremia itself cannot be treated directly, as it is the result of kidney disease. For this reason, the renal insufficiency must primarily be treated in order to improve the uremia.
The treatment of choice here is usually immediate dialysis ("blood washing") to filter out the high concentration of urinary substances from the blood - a job that the kidneys do in healthy people. Depending on the age of the patient and any pre-existing conditions, attempts can be made to therapeutically improve kidney function. However, a kidney transplant may also be considered as a long-term solution.
Treatment for uraemia consists of immediate dialysis to cleanse the blood of harmful substances @ Tyler Olson /AdobeStock
The following measures can be used as supplementary therapy, in particular to improve or maintain kidney function:
- a low-protein but high-calorie diet, as a lower protein intake also results in less urea,
- a balanced fluid intake to relieve the kidneys,
- taking diuretics to support electrolyte and water excretion.
Urinary intoxication, or uremia, is a life-threatening condition if left untreated. However, immediate medical treatment can save the patient's life. Dialysis is nevertheless necessary in the long term, and in many cases a kidney transplant is also required.
The need for dialysis in renal failure severely restricts the patient's everyday life and quality of life. Only a successful kidney transplant significantly improves the patient's life situation and general health.
The kidney is the most frequently transplanted organ @ Iryna /AdobeStock
The best protection against kidney failure with uraemia is to have kidney damage checked by a specialist. As a patient, you should also make sure that you have regular check-ups if you have kidney weakness, keep an eye on how much you drink and how much urine you excrete, and avoid drugs and substances that damage the kidneys. In this way, further kidney damage can usually be slowed down or even stopped completely.
As uraemia is caused by kidney disease, it falls under the remit of nephrology. Specialized kidney centers or kidney doctors will make the diagnosis and plan further treatment steps with you. Kidney transplants are also carried out as surgical therapy by urology. In particularly well-equipped centers in Germany, such operations can now even be performed with robotic assistance.