| Aquagenic pruritus | |
|---|---|
| Specialty | Dermatology  |
Aquagenic pruritus is a skin condition characterized by the development of severe, intense, prickling-like epidermal itching without observable skin lesions and evoked by contact with water. [1] [2]
| Aquagenic pruritus | |
|---|---|
| Specialty | Dermatology |
Aquagenic pruritus is a skin condition characterized by the development of severe, intense, prickling-like epidermal itching without observable skin lesions and evoked by contact with water. [1] [2]
Presentation varies from person to person. Some people have discrete attacks, which can last between 10 and 120 minutes [3] while others are symptomatic almost constantly due to atmospheric humidity levels and/or sweating. Itching most frequently occurs on the legs, arms, chest, back, and abdomen, though it can also occur elsewhere. [4]
Itching on contact with water that also includes hives is known as aquagenic urticaria.
The exact mechanism of the condition is unknown. Some studies have suggested the itching occurs in response to increased fibrinolytic activity in the skin, [5] [6] inappropriate activation of the sympathetic nervous system, [7] increased activity of acetylcholinesterase, [8] [9] or an increase in mast cell degranulation that releases histamine and other chemicals into the body. [10]
No definitive medical test is known for aquagenic pruritus. Rather, diagnosis is made by excluding all other possible causes of the patient's itching, including polycythemia vera. Since pruritus is a symptom of many serious diseases, it is important to rule out other causes before making a final diagnosis. [11]
Beta-Alanine, a nonessential amino acid and freely available as a nutritional supplement in many countries, has been found to suppress or significantly reduce the symptoms in many cases. [12] Anecdotal evidence indicates that it is commonly consumed in doses of 750 mg to 2 grams before water contact. [13] A study found that a dose of 2 grams twice per day led to a "dramatic and sustained improvement" of symptoms in a 13-year-old male patient, allowing him to comfortably shower, exercise, and swim. [12]
Other treatment is usually focused on topical itch management. This can be effected by the application of hot water at the end of a bath or shower, antipruritic lotions or creams such as lotion containing capsaicin, using phototherapy, or the application of hot or cold packs to the skin after water contact. [14] Paradoxically, hot baths or showers help many patients, possibly because heat causes mast cells in the skin to release their supply of histamine and to remain depleted for up to 24 hours afterward. [15] [16]
H1 and H2 blockers, such as loratadine, doxepin, or cimetidine, have historically been the first line of pharmacological treatment, but not all people find relief with these medications. When antihistamines do work, loratadine seems to be the most effective for mild cases and doxepin most effective for more severe cases.
Naltrexone, hydrocortisone, or propranolol may relieve itching for some people. [17] [7]
Sertraline or other Selective serotonin reuptake inhibitors (SSRIs) is also a line of treatment. Gabapentin is very helpful.
The name is derived from Latin: aquagenic, meaning water-induced, and pruritus, meaning itch.
Lichen simplex chronicus (LSC) is thick leathery skin with exaggerated skin markings caused by sudden itching and excessive rubbing and scratching. It generally results in small bumps, patches, scratch marks and scale. It typically affects the neck, scalp, upper eyelids, ears, palms, soles, ankles, wrists, genital areas and bottom. It often develops gradually and the scratching becomes a habit.
Itch is a sensation that causes the desire or reflex to scratch. Itches have resisted many attempts to be classified as any one type of sensory experience. Itches have many similarities to pain, and while both are unpleasant sensory experiences, their behavioral response patterns are different. Pain creates a withdrawal reflex, whereas itches leads to a scratch reflex.
Hives, also known as urticaria, is a kind of skin rash with red, raised, itchy bumps. Hives may burn or sting. The patches of rash may appear on different body parts, with variable duration from minutes to days, and does not leave any long-lasting skin change. Fewer than 5% of cases last for more than six weeks. The condition frequently recurs.
Antipruritics, abirritants, or anti-itch drugs, are medications that inhibit the itching often associated with sunburns, allergic reactions, eczema, psoriasis, chickenpox, fungal infections, insect bites and stings like those from mosquitoes, fleas, and mites, and contact dermatitis and urticaria caused by plants such as poison ivy or stinging nettle. It can also be caused by chronic kidney disease and related conditions.
Pityriasis rosea is a type of skin rash. Classically, it begins with a single red and slightly scaly area known as a "herald patch". This is then followed, days to weeks later, by an eruption of many smaller scaly spots; pinkish with a red edge in people with light skin and greyish in darker skin. About 20% of cases show atypical deviations from this pattern. It usually lasts less than three months and goes away without treatment. Sometimes malaise or a fever may occur before the start of the rash or itchiness, but often there are few other symptoms.
Cold urticaria is a disorder in which large red welts called hives (urticaria) form on the skin after exposure to a cold stimulus. The hives are usually itchy and often the hands and feet will become itchy and swollen as well. Hives vary in size from about 7 mm in diameter to as big as about 27 mm or larger.
Mycosis fungoides, also known as Alibert-Bazin syndrome or granuloma fungoides, is the most common form of cutaneous T-cell lymphoma. It generally affects the skin, but may progress internally over time. Symptoms include rash, tumors, skin lesions, and itchy skin.
Urticaria pigmentosa (also known as generalized eruption of cutaneous mastocytosis (childhood type) ) is the most common form of cutaneous mastocytosis. It is a rare disease caused by excessive numbers of mast cells in the skin that produce hives or lesions on the skin when irritated.
Livedo reticularis is a common skin finding consisting of a mottled reticulated vascular pattern that appears as a lace-like purplish discoloration of the skin. The discoloration is caused by reduction in blood flow through the arterioles that supply the cutaneous capillaries, resulting in deoxygenated blood showing as blue discoloration. This can be a secondary effect of a condition that increases a person's risk of forming blood clots, including a wide array of pathological and nonpathological conditions. Examples include hyperlipidemia, microvascular hematological or anemia states, nutritional deficiencies, hyper- and autoimmune diseases, and drugs/toxins.
Pruritic urticarial papules and plaques of pregnancy (PUPPP), known in United Kingdom as polymorphic eruption of pregnancy (PEP), is a chronic hives-like rash that strikes some women during pregnancy. Some skin changes are known to occur in people who are pregnant while other skin conditions, or dermatoses, that people have prior to getting pregnant will become altered or symptoms will increase. Pruritic urticarial papules and plaques of pregnancy (PUPPP) is one of many skin conditions that is specific to pregnancy and occurs in about 1 in every 160 (0.625%) of pregnancies.
Prurigo nodularis (PN), also known as nodular prurigo, is a skin disease characterised by pruritic (itchy) nodules which usually appear on the arms or legs. Patients often present with multiple excoriated lesions caused by scratching. PN is also known as Hyde prurigo nodularis, Picker's nodules, atypical nodular form of neurodermatitis circumscripta, lichen corneus obtusus.
Referred itch or mitempfindung is the phenomenon in which a stimulus applied in one region of the body is felt as an itch or irritation in a different part of the body. The syndrome is relatively harmless, though it can be irritating, and healthy individuals can express symptoms. Stimuli range from a firm pressure applied to the skin – a scratch – to irritation or pulling on a hair follicle on the skin. The referred sensation itself should not be painful; it is more of an irritating prickle leading to the compulsion to scratch the area. The stimulus and referred itch are ipsilateral. Also, because scratching or putting pressure on the referred itch does not cause the stimulus area to itch, the relationship between the stimulus and the referred itch is unidirectional. The itching sensation is spontaneous and can cease with continued stimulation.
Pruritus ani is the irritation of the skin at the exit of the rectum, known as the anus, causing the desire to scratch. The intensity of anal itching increases from moisture, pressure, and rubbing caused by clothing and sitting. At worst, anal itching causes intolerable discomfort that often is accompanied by burning and soreness. It is estimated that up to 5% of the population of the United States experiences this type of discomfort daily.
Cholinergic urticaria is a type of hives (urticaria) that is triggered by an increase in body temperature, such as during exercise, sweating, or exposure to heat. It is also sometimes called exercise-induced urticaria or heat hives. The condition is caused by an overreaction of the immune system to the release of histamine and other chemicals in response to the increase in body temperature. This results in the characteristic red, itchy, and sometimes raised bumps or welts on the skin that are associated with hives.
Aquagenic urticaria, also known as water allergy and water urticaria, is a rare form of physical urticaria in which hives develop on the skin after contact with water, regardless of its temperature. The condition typically results from contact with water of any type, temperature or additive.
Notalgia paresthetica or Notalgia paraesthetica (NP) (also known as "Hereditary localized pruritus", "Posterior pigmented pruritic patch", and "subscapular pruritus") is a chronic sensory neuropathy. Notalgia paresthetica is a common localized itch, affecting mainly the area between the shoulder blades (especially the T2–T6 dermatomes) but occasionally with a more widespread distribution, involving the shoulders, back, and upper chest. The characteristic symptom is pruritus (itch or sensation that makes a person want to scratch) on the back, usually on the left hand side below the shoulder blade (mid to upper back). It is occasionally accompanied by pain, paresthesia (pins and needles), or hyperesthesia (unusual or pathologically increased sensitivity of the skin to sensory stimuli, such as pain, heat, cold, or touch), which results in a well circumscribed hyperpigmentation of a skin patch in the affected area.
Brachioradial pruritus is an intense itching sensation of the arm usually between the wrist and elbow of either or both arms. The itch can be so intense that affected individuals will scratch their own skin to a bleeding condition.
Adrenergic urticaria is a skin condition characterized by an eruption consisting of small (1-5mm) red macules and papules with a pale halo, appearing within 10 to 15 min after emotional upset. There have been 10 cases described in medical literature, and involve a trigger followed by a rise in catecholamine and IgE. Treatment involves propranolol and trigger avoidance.
Senile pruritus is one of the most common conditions in the elderly or people over 65 years of age with an emerging itch that may be accompanied with changes in temperature and textural characteristics. In the elderly, xerosis, is the most common cause for an itch due to the degradation of the skin barrier over time. However, the cause of senile pruritus is not clearly known. Diagnosis is based on an elimination criteria during a full body examination that can be done by either a dermatologist or non-dermatologist physician.