Uremic pruritus is chronic itching in dialysis patients. The exact mechanism of formation is not yet known. Curative therapy is only possible with a kidney transplant.
What is uremic pruritus?
Chronic itching, also known as uraemic pruritus, is very common in dialysis patients. The Latin term is pruritus uraemicus. It is assumed that approximately 50 to 90 percent of all dialysis patients are affected by pruritus uraemicus. This is not an independent disease, but a symptom. For king-kopetzky syndrome 101, please visit photionary.com.
The itching is difficult to combat and leads to sleep disturbances and psychological impairments. It has been observed that hemodialysis patients have a higher percentage of itching than peritoneal dialysis patients. Nevertheless, both procedures can lead to uremic pruritus. Hemodialysis takes place outside the body.
The blood is drained from the body, cleaned via membranes and then returned to the body. Peritoneal dialysis takes place inside the body. The peritoneum acts as a filter membrane. In this procedure, a dialysis solution is filled into the abdominal cavity, which remains there for several hours and absorbs substances from the blood that are excreted in the urine via the biological membrane (peritoneum).
After a few hours, this used solution is exchanged for fresh dialysis solution. Almost 100 percent of dialysis patients suffer from various skin diseases in addition to uraemic pruritus. These skin diseases can also lead to excruciating itching. However, uremic pruritus must be differentiated from other forms of itching. It has been established that this particular form of pruritus only occurs in patients requiring dialysis.
The mechanism of origin of uremic pruritus has not yet been fully elucidated. There are some attempts at an explanation, but these have not yet been verified. In kidney failure, the skin often dries out. Many patients also suffer from anemia. The serum level of magnesium and aluminum is often elevated. Parathyroid hormone may also be elevated. All of these factors cause itching.
Finally, the itching can also be triggered by concomitant diseases of renal insufficiency. These diseases include diabetes mellitus, hypothyroidism or hepatitis. In some cases, drug intolerance can also be responsible. An increased release of histamine as a cause of the itching is also discussed. It is known that the concentration of mast cells in the skin is increased in the case of renal insufficiency.
Mast cells have a function for the immune system by releasing histamine. Thus, histamine irritates the nerve endings, causing the sensation of itching. Substance P is also increased in chronic kidney failure. This stimulates the opioid receptors, which can also be felt as itching. However, it is observed that this tormenting pruritus usually develops during or after dialysis. However, it can also occur between dialysis sessions.
Symptoms, Ailments & Signs
Uremic pruritus is not an independent disease, but only occurs in the context of stages 4 and 5 renal insufficiency requiring dialysis. Renal insufficiency in stages 1 to 3 are still largely symptom-free. In addition to excruciating, persistent itching, patients also suffer from the other typical symptoms of stage 4 and 5 renal failure.
These include pain in the kidney area, brown urine, kidney stones or even inflammation of the kidney pelvis. Furthermore, nausea, vomiting, reduced mental performance, loss of appetite, water retention, shortness of breath and, above all, skin changes occur. The skin changes appear in the form of scratch marks, open wounds or scars and are the result of scratching with the excruciating itching.
Diagnosis & course of disease
Itching can be diagnosed as uremic pruritus if it occurs during, after, or between dialysis treatments. It usually only lasts a few minutes and occurs regularly. The diagnosis “uraemic pruritus” can be made if it occurs three times within two weeks. Physical examination reveals scratch marks.
Uremic pruritus is primarily associated with severe discomfort for those affected. The possible complications are similar to those of stage four and five renal failure. This can lead to the formation of kidney stones or even inflammation of the renal pelvis. Furthermore, severe gastrointestinal complaints, water retention and shortness of breath occur.
In the advanced stage, those affected also suffer from noticeable skin changes caused by constant scratching as a result of the tormenting itching. Typical are open wounds, scratches and later also scars. Depending on how the underlying disease progresses, uremic pruritus can cause further complications or be symptom-free for the person affected.
As a rule, no major problems arise during treatment. However, the urea-containing creams can cause skin irritation and occasionally increase the itching. Radiation treatment carries the risk of bone disorders and changes in tissue structures, which in rare cases can develop into cancer.
Painkillers and anti-inflammatories cause side effects and interactions in some patients, such as stomach pain or sensory disturbances. People with allergies are at risk of anaphylactic shock.
When should you go to the doctor?
In the case of this disease, medical treatment must take place in any case. This is a very unpleasant complication of dialysis, which can be limited in many cases. The affected person should therefore consult a doctor as soon as the first signs and symptoms of the disease appear, so that the symptoms do not worsen further or other complications occur. Early diagnosis has a positive effect on the further course of the disease. A doctor should be contacted if the person affected suffers from severe itching during dialysis.
Shortness of breath or a severe loss of appetite can also indicate this disease. It is not uncommon for those affected to suffer from vomiting or severe nausea. If these symptoms occur over a longer period of time and do not go away on their own, a doctor must be contacted. In the case of this disease, the doctor who is responsible for the dialysis should be contacted. However, a complete cure can only be achieved by transplanting a kidney.
Treatment & Therapy
A curative treatment of uremic pruritus is only possible with a kidney transplant. There are no other cures for kidney failure that requires dialysis. However, there are some symptomatic treatment options that promise to relieve the itching. Topical, physical, surgical and systemic treatments are offered.
Creams containing urea are used in topical therapy to ensure that the skin is kept moist. Furthermore, mild soaps must be used. Physical therapy, in turn, is phototherapy with UV-B radiation. Radiation relieves the tormenting itching. However, the mechanism of action of the radiation has not yet been elucidated.
If the uremic pruritus is caused by an overactive parathyroid gland, surgical removal of the parathyroid corpuscles promises improvement. Finally, systemic treatments with various drugs can be carried out. However, the chances of success are different.
In many cases, the treatment results are also unsatisfactory. Gamma-linolenic acid has a certain effectiveness because it inhibits the formation of lymphocytes and the synthesis of lymphokines. This prevents inflammatory reactions.
Since uremic pruritus is the result of acute or chronic renal failure, prevention of renal disease is a priority. Kidney damage can be caused by high blood pressure or diabetes, among other things.
Therefore, the prophylaxis of kidney failure and uremic pruritus includes strict weight control, reducing obesity, plenty of exercise, limiting the consumption of table salt, a balanced diet and not smoking and alcohol. The diet should be low in calories and fat. At the same time, eating plenty of fruit and vegetables is recommended.
In the case of uremic pruritus, the focus of follow-up examinations and treatments is generally the symptomatic treatment of the itching. Aftercare can only be limited to relieving or suppressing the itching. Uremic pruritus itself cannot be cured medically. A corresponding therapeutic treatment concept is missing.
Because according to the rules, uremic pruritus is only a symptom of a kidney dysfunction (e.g. renal insufficiency). The itching only disappears abruptly when the underlying disease has healed. Only a kidney transplant can help here. Until then, uremic pruritus can only be effectively treated with a combination of several drugs. The task of aftercare is to continue the clinically started medication for the person concerned and to adapt it to the symptoms of the disease.
For this purpose, the person concerned must be presented regularly on an outpatient basis. In addition, the affected person must learn during follow-up care to adapt their living conditions to the disease. The itching can also be relieved by numerous self-help measures. It is important to first switch off the trigger factors (triggers of the itching) in the everyday life of the affected person.
Light clothing (preferably cotton) should be worn. When bathing or showering, the water temperature should not exceed 35 degrees Celsius. In order to prevent the skin from drying out, it is advisable to set up air humidifiers in rooms. In addition, personal hygiene should not be overdone (that is, not too hot, not too often, and not too long).
You can do that yourself
Uremic pruritus requires medical treatment. The condition is treated surgically or conservatively, which should already result in a significant improvement in the individual symptoms. Medical treatment can be supported by various self-help measures.
The first thing that is important is strict compliance with the medical specifications. Above all, the intake of medication, as is required for systemic treatment, must be carried out exactly according to the instructions. Otherwise, serious complications can arise. Sport is also recommended. Gentle physical activity supports recovery just as effectively as rest and rest. The training plan is best worked out with a physiotherapist.
Diet, which must be particularly gentle in the case of advanced kidney disease, also requires detailed analysis by an expert. Patients have to drink a lot and eat a diet low in fat and sugar in order not to put additional strain on the kidneys. The patient should keep a complaint diary and note any unusual symptoms. In addition, any side effects of the prescribed antihistamines must be written down and reported to the doctor.
The self-help measures mentioned should be discussed with the doctor. The doctor can name further measures to support the recovery process.