What does an itch in the left palm mean?

Type and location can indicate causes of itching

Itching is always a diagnostic and therapeutic challenge. He employs not only dermatologists but also general practitioners; it is an accompanying symptom of many internal, oncological and neurological diseases. Since the itching is probably based on different pathological mechanisms, there are different therapy options depending on the underlying disease.

Pruritus often occurs in liver and kidney diseases

Itching of an unclear cause is one reason to go in search of a diagnosis. Although pruritus occurs most frequently in liver and kidney diseases, write Professor Thomas Mettang from the German Clinic for Diagnostics in Wiesbaden and his colleagues (Der dermatologist 57, 2006, 395).

Infections, haematological or endocrine diseases can also be the cause. Pruritus also occurs in all stages of tumor diseases and can even precede the diagnosis by years. Anorexia patients also sometimes have itching. Rare causes are multiple sclerosis, cerebral infarction or brain tumors.

Scratch artifacts are usually the only skin changes that can be seen on clinical examination. Drug-induced pruritus may be accompanied by a measles-like rash. Ten to 20 percent of lymphoma and leukemia patients have papules, lumps, plaques, or ulcers. In HIV infection or hypothyroidism, the itching is often related to dry skin.

The type and localization of the symptoms vary depending on the underlying disease:

  • 25 to 50 percent of patients with end-stage renal failure have generalized itching, especially on the back, shunt arm (on dialysis) and face.
  • Hepatic pruritus is also mostly generalized. Those affected can hardly alleviate it by scratching. Typical locations are the palms of the hands, the soles of the feet and the contact surfaces of the clothing.
  • In Hodgkin's disease, itching usually begins at night in the legs before generalizing. A relapse of the disease can also be announced by itching.
  • For polycythemia vera a sharp itchiness after bathing or with temperature fluctuations is typical.
  • Pruritus of the nostrils has been observed in brain tumors.

Investigations into the causes of the itching have so far often provided contradicting results. In kidney diseases, for example, parathyroid hormone and histamine are suspected to be causative factors. However, antihistamines are usually ineffective, so the colleagues. The importance of antigens and uremia toxins is also unclear. Elevated vitamin A tissue concentrations, inflammatory processes, microcalcifications in the skin or the increased stimulation of µ-opioid receptors by endorphins are also suspected.

In the case of pruritus, the focus is initially on therapy against the underlying disease, such as the elimination of cholestasis in liver and biliary tract diseases.

Treatment options for kidney diseases are high-dose activated charcoal (6 g / d for two to three weeks), UVB light radiation or the prescription of the opioid antagonist naltrexone, the serotonin receptor antagonist ondansetron or the anti-epileptic gabapentin, recommends Mettang's team. Acupuncture or electro acupuncture should also be effective.

Medicines relieve itching in liver disease

In liver disease, there have been positive reports about dronabinol, an agonist of the cannabinoid B1 receptor, and about the serotonin reuptake inhibitor sertraline. Colestyramine helps many patients, but often only temporarily. In the case of kidney or liver failure, an organ transplant leads to a significant improvement in the itching or even to freedom from symptoms.

If the itching is particularly due to dry skin, patients can often be helped with moisturizing ointments and oil baths. The cause of vulvar pruritus, which affects around every fifth patient with diabetes, is often a candida or dermatophyte infection. (ner)

Itching and cancer

Itching is known as a paraneoplastic phenomenon. A generalized pruritus of unclear cause should therefore also suggest a malignant disease, according to Professor Thomas Mettang from Wiesbaden and his colleagues. This is especially true for older men with iron deficiency.

Pruritus can arise directly as a result of tumor growth, for example in mammary, colon, or prostate Ca.