Itching without rashes

A common symptom such as itching is usually accompanied by a rash. However, itching without rashes can also occur due to a wide range of pathological conditions and systemic diseases.

In terms of extent, pruritis without visible skin changes may be generalized (widespread) or localized, and in terms of duration, acute, recurrent, or chronic.

Causes of the itching without rashes

Itching without rashes - pruritus sine materia (Latin for itching without matter), that is, without primary skin lesions - is usually not related to skin diseases, and in dermatology is a diagnosis of exclusion.

The simplest case - itchy hands without rashes - is caused by dry skin on the hands. But it should be taken into account that dry skin (xerosis) can provoke thyroid and metabolic disorders.

As noted by experts, itching of the skin on the hands and all over the body may for some time precede the appearance of a rash, for example, when infected with intradermal scabies (Sarcoptes scabiei) and the development of an infection such as scabies; with shingles, when burning, itching of the lower back without rashes and painful sensations occur several days before the Varizella zoster virus (VZV) manifests itself with a typical pustular rash. [1]

Among the most likely experts consider such causes of pruritus sine materia:

• the presence of diabetes mellitus;
• kidney disease leading to terminal renal failure (especially in patients on dialysis);
• hepatitis, primary biliary cirrhosis, [2] primary sclerosing cholangitis, [3] as well as liver damage by parasites such as giardia (Giardia intestinalis), [4] opisthorchias - Opisthorchis felineus (cat's biceps) [5] or fasciola (Fasciola hepatica). [6] By the way, if a child has itchy skin without rashes, the first thing to suspect is the presence of helminths.

Not accompanied by a rash have skin itching in the list of symptoms:

• pancreatic diseases, including cancer;
• Thyroid problems - thyrotoxicosis, hyperthyroidism;
• Iron deficiency in the body (iron deficiency anemia) - provokes facial itching without rashes;
• refractory anemia or myelodysplastic syndrome; [7]
• Erythremia or true polycythemia, associated with benign proliferation of blood cells; [8]
• HIV infection.

According to oncologists, the first signs of cancerous degeneration of tissues of various organs can be manifested by itching in the area of regional lymph nodes. Such itching is called paraneoplastic itching and is noted in leukemia, lymphoma, plasmacytoma, as well as gallbladder and liver cancer, prostate carcinoma, lung adenocarcinoma and carcinoid syndrome.

Neurogenic or neuropathic is referred to as:

• Itchy hands and feet without rashes in multiple sclerosis; [9]
• Itching of the upper chest and back without rashes in notalgia paresthetica, a hereditary form of chronic sensory neuropathy; [10]
• Itching of the lumbar region without rashes in cases of lesions of the nerve roots of the lumbar spinal cord in diseases of the spine.

In stress, depression and mental disorders (psychosis, obsessive-compulsive disorder, schizophrenia) itching without any morphologic changes in the skin is considered psychogenic or psychosomatic.

Itching without visible skin damage caused by contact with water is called aquagenic.

Pregnant women experience severe itchy skin on the abdomen without rashes due to stretching of the skin and increased hormone levels; more information in the article - Itching during pregnancy.

In addition, itchy skin without redness and rashes can also be caused by medications: opiates, statins, anticoagulants, some hypotensive drugs, antimalarial drugs, antibiotics, oral contraceptives. And facial itching without rashes can be the result of taking niacin (vitamin B3 or nicotinic acid).

Risk factors

Risk factors for physiologic pruritus without any rash elements (in the form of papules, vesicles, macules or pustules) are dry skin, which may be associated with the use of too hot bathing water, hereditary features of the skin, age-related xerosis.

There is a high prevalence of generalized pruritus without rash in the elderly.

Risk factors for pathologic pruritus sine materia are endocrine, hematologic, systemic, neurologic diseases and psychiatric conditions in which this symptom appears.

Pathogenesis

The general mechanism of pruritus is discussed in the publication - Pathogenesis of itchy skin.

In addition to age-related physiological changes in the skin - deterioration of its hydration and reduced sebum production, itching all over the body without rashes after the age of 65 is associated with age-related sensory neuropathy, changes in the immune system and often unjustified taking of several medications (polypragmasy).

Pruritus without rash often affects the lower extremities of diabetic patients, and its pathogenesis is related to prolonged hyperglycemia and poor circulation. Itching is often a symptom of nerve fiber damage in the skin - diabetic polyneuropathy. Read more - Itching in type 1 and type 2 diabetes.

Itching without rashes in pregnancy or pruritus gravidarum is caused by an increase in serum bile acid concentration due to intrahepatic cholestasis at the end of the second or third trimester (called cholestatic hepatosis of pregnancy). Why it occurs in some pregnant women, provoking itchy skin of the extremities and jaundiced body skin, is not fully understood. This condition can have a negative impact on the outcome of pregnancy.

Paraneoplastic itching is the result of the activity of proinflammatory cytokines released by immune cells in response to malignant transformation of cells, and substances produced by tumor cells that can affect both directly on nerve endings and cause the release of histamine. And in pancreatic cancer (especially if the tumor has formed in the head of the pancreas) there is often obstruction of the bile ducts, bile stasis and subsequent accumulation of bile salts in the skin, provoking itching. Other symptoms may include jaundice, abdominal pain, ascites, and stool discoloration.

In some cases, itching without rashes - especially aquagenic itching - may appear months before the diagnosis of cancers such as non-small cell lung cancer or lymphoma. Intense pruritis always begins after contact with water in polycythemia.

The mechanism of psychogenic pruritus in patients with CNS disorders and mental health problems is due to acetylcholine activation of sensory areas of the anterior cortex, supplementary motor areas, and inferior parietal lobe.

And itching under stress - with the effect of adrenaline on β2-adrenoreceptors - is mediated by activation of the hypothalamic-pituitary system and release of neurotransmitters (neuropeptides, neurotrophins, lymphokines) from nerve endings and dermal cells, as well as increased release of histamine by skin mastocytes.

Diagnostics of the itching without rashes

Because the etiology of pruritus is heterogeneous, diagnosing the underlying condition can be quite challenging in some cases.

More information in the material - Diagnosing Itchy Skin Disease

Medical history (including a list of medications taken) and family history are key. Examination of the skin (as well as nails and hair); palpation of lymph nodes, liver, and spleen are also necessary.

Systemic tests include blood tests: full clinical, HIV, sugar, thyroid hormone, hematocrit and ferritin, bilirubin, alkaline phosphase and transaminase, urea and creatinine, antibodies (IgE, IgG, IgM), PCR for VZV DNA. A urinalysis and a coprogram are also performed. Other laboratory tests may be needed in any combination.

Instrumental diagnostics may include various radiologic studies, ultrasound of the thyroid gland, liver and gallbladder, etc.

Differential diagnosis, looking at the localization of pruritus, its nature and triggers, and the presence of other symptoms, plays a major role.

Treatment of the itching without rashes

In each case treatment for itchy skin should be directed at the underlying condition associated with it.

Iron deficiency anemia can be treated by taking iron sulfate supplements and eating more foods rich in this trace element (red meat, eggs, legumes, green leafy vegetables, nuts, etc.).

If parasite infestation is detected, antihelminthic drugs are used, see - Best worming pills.

Oral medications may be used in therapy to relieve/reduce itching. These are primarily Fencarol, Loratadine (other trade names are Lotaren, Claritin), Terfenadine (Trexyl), Fexofenadine and other antihistamines.

For neurogenic pruritus and pruritus associated with chronic kidney disease, anticonvulsants may be prescribed - Gabapentin (Gabagama, Gabalept, Gabastadine) or Pregabalin.

In cases of paraneoplastic and psychogenic pruritus without rashes and pruritus with cholestasis it is practiced to use antidepressants of the group of selective serotonin reuptake inhibitors - Paxil (Paroxetine), Sertraline (Sertraloft, Asentra), as well as tricyclic antidepressants acting on histamine H1-receptors (Doxepin or Mirtazapine).

The drug of the group of calcineurin inhibitors Cyclosporine has immunosuppressive effect and is used for generalized pruritus (contraindicated in pregnant women). The standard daily dose is 2.5 mg per kg of body weight (divided into two doses). In the list of its side effects: headache, nausea, vomiting, abdominal pain, cramps, kidney dysfunction, blood changes.

It is recommended to take B vitamins, as well as A, E, D.

Depending on the etiology of itching, the doctor may recommend topical agents: ointments for itching (including corticosteroids, which may not be used for more than two consecutive weeks) or creams for itching - especially moisturizing and "cooling" due to the menthol content.

Physiotherapy treatment includes phototherapy (UVO), which is most effective for itchy skin in the elderly.

Folk treatment consists of external application of a mixture of castor oil with menthol (in proportion 3:1) or turmeric powder (2:1), massage of the itchy area of the skin with an ice cube, as well as slightly warm baths with ground and steamed oatmeal or English salt.

You can try and herbal treatment: in the form of cool compresses with decoctions of chamomile flowers, peppermint or melissa, anise seeds or comfrey root.

Complications and consequences

Immediate consequences and complications - secondary skin damage due to combing: eczematous changes (open wounds and scabs), lichenization (thickening of the skin at the sites of combing), excoriation (scratching), hyperpigmentation (brown spots), hypopigmented atrophic scars.

These lesions can be painful, and they can also become infected.

Prevention

Prevention of dry skin is to drink enough fluids, avoid washing with too hot water and use moisturizing creams. Learn more - Moisturizing creams for dry and flaky skin.

And the real prevention of most of those diseases and conditions in which there is skin itching without rashes, as noted by doctors, almost impossible.

Forecast

The prognosis of itching without rashes is certainly positive when the skin is dry - if the skin is properly cared for, and itching in pregnant women, as it goes away after childbirth. Also in cases of discontinuation of a medication that causes itching without rashes.

In other cases, everything depends on the nature of the underlying disease and the success of its treatment.