Urticaria

Causes of Urticaria (Hives)

Like many other disease conditions, we know what happens in urticaria more that what exactly causes urticaria (hives). In almost half the cases we know what causes or induces urticaria; and half the time, the patients or we have no clue as to its exact cause.

Many people including some doctors believe that urticaria is allergic in nature. Actually, tt must be noted that Urticaria is not always allergic in nature. There are allergic and non-allergic causes for chronic urticaria. The non-allergic causes include auto-immunity related, hormonally triggered, stress triggered, exercise, drugs, temperature based and other factors.

We shall try to examine some of the most common exciting factors known to induce urticaria (hives), which may be grouped as:

Allergens: A large number of allergens have been identified as causative agents for some cases of urticaria. It may be noted that urticaria is an individual hypersensitivity and the following factors may not cause urticaria in all urticaria-prone individuals.

Food allergens: Milk, cheese, egg, protein products, wheat, cereals, nuts, certain daals as used in India, peas, orange, fish, chicken, etc. Synthetic and natural food additives and artificially-flavored food articles.

Urticaria and alcohol: True anaphylactic reactions to alcohol (ethanol) are rare and most reactions to ingested alcoholic beverages are secondary to other chemicals in the beverage such as metabisulfite, papain, dyes or yeasts. However, there are reports of true allergic reactions in which the offending agent was shown to be the ethanol itself. Generally the symptoms of anaphylaxis occur in such patients following the ingestion of beer and/or wine. Urticaria rashes have been reported with ethanol ingestion; and hives on contact with ethanol have also been reported for some patients of urticaria.

Environmental factors : Exposure to pollen, house-dust, buffalo dander, fungi, change in temperature, etc. are known exciting factors. Extreme cold, heat, pressure may also induce urticaria.

Drugs:  The major cause for urticaria are man-made drugs such as antibiotics (Penicillin), NSAIDs, anti-inflammatory drugs (aspirin, indomethacin), vaccinations, foreign sera, hormonal preparations, contraceptive pills, etc. Animals treated with penicillin excrete a small amount of it in the milk sufficient to cause urticaria in sensitive individuals.

Cholinergic factors : Urticaria often gets triggered or aggravated by exercise, pressure on some part of the body as well as change in temperature of body after sweating. Such changes affect nerve ending of skin which lead to development of urticaria rash. In this variety of urticaria one experiences itching, burning and local heat on skin.

Urticaria and Cocaine:  There have been reports of morphine-induced hives in some people. Bronchospasm may occur in some patients who smoke cocaine or in those who inject heroin. This may occur more often in patients who have a previous history of asthma. Hypersensitivity pneumonitis to cocaine has also been described and is associated with elevated levels of IgE.

Infections and Infestations : Insect bites, Fungal, protozoal, frequent bacterial infections (Urinary tract), viral infections (Hepatitis), helminthiasis (worm infestations such as round worms, tapeworms), etc. are factors known to cause urticaria. Domestic contact with the pet animals should be examined as cause for urticaria.

Synthetic Products : Use of personal products such as deodorant, perfume, and talcum powder, cosmetic products, animal derivatives, and similar synthetic substances may induce this disorder.

Emotional factors:  Especially in chronic, recurring cases of urticaria the role of emotional factors must be examined. Emotional stresses may directly or indirectly make on susceptible to develop a tendency to urticaria. The psychological factors may work as exciting, aggravating or maintaining cause. Especially, if you are under prolonged stress, anxiety, sadness or insecurity, such intense emotions could alter your immunological state and in turn lead to hypersensitivity.

Autoimmune Causes: Chronic urticaria is now understood to have autoimmune link. Presence of auto antibodies against Immunoglobulin E (IgE), CD23 (FcεRII or Fc epsilon RII) which releases histamine, hence leading to chronic urticaria.

Systemic and General Disease: Urticaria in some cases may present as a sign of other systemic or general internal disease such as hormonal disorders (hyperthyroidism), SLE, polycythaemia, reticuloses, etc. In certain variety of malignancies (cancer) urticaria may present as a precursor.

Idiopathic Cause: No list of causation is complete without adding a paragraph of ‘Idiopathic’ which simply implies causes which are unknown.

Urticaria Pigmentosa (Mastocytosis)

Urticaria pigmentosa is a skin disease, which is a form of urticaria as well as mastocytosis, in which you find brown, intensely itching patches on skin. On rubbing the spots, one gets hives or urticarial patches.

It is one of the forms of mastocytosis. For understand mastocytosis, we need to understand a bit about mast cells. Mast cells are normal cells found in skin all over the body. Mast cells contain certain granules which when activated or stimulated, lead to release of histamine and other such chemicals, leading to the condition called mastocytosis. You may say, mast cells are inflammatory cells.

Incidence: Urticaria pigmentosa is most commonly seen in infants and children but can also be found in adults.

Causes

The exact cause of this uncommon disease is unknown but recent research suggests genetic change in a protein (called c-kit) on the surface of mast cells may result in the abnormal proliferation of these cells.

Variety of factors can cause or worsen the symptoms of urticaria pigmentosa:

• Physical stimuli such as heat, friction, and excessive exercise
• Bacterial toxins
• Venom
• Eye drops containing dextran
• Alcohol
• Morphine
• Emotional stress

Symptoms

• Brownish lesions on skin are seen typically around chest and forehead.
• Rubbing the skin sore causes hive like bump.
• A fluid filled blister may form if it is scratched, especially seen in younger children.
• Face may become flushed.
• In severe cases diarrhea, headache and palpitation may be seen.

Darier’s sign

A typical presentation called Darier’s sign is observed in Urticaria pigmentosa. By rubbing one of the brown patches the rubbed area becomes reddened, swollen and itchy. This confirms the presence of mastocytosis.

Something about mast cells

Mast cells are normally widely distributed in the skin. They contain granules that contain histamine and other chemicals. When the mast cell is disturbed, these chemicals are released into the surrounding skin. The chemicals make the blood vessels leaky, resulting in localized itching, swelling and redness.

Diagnosis and Investigations

• The disease is most often diagnosed clinically
• Doctors can confirm the presence of mast cells by rubbing the skin. If hives appear, it most likely signifies the presence of urticaria pigmentosa.
• Skin biopsy shows an increase in mast cells and confirms the diagnosis.

If there are any symptoms suggesting internal involvement the following tests may be helpful

• X-rays of skull and long bones may show areas of bone thinning, or a diffuse ground glass appearance
• Urinary histamine levels or 1,4-methylimidazole acetic acid may be elevated

Prognosis

• It goes away on its own till the time of puberty in 50% of the cases but medication is required as it is a troublesome disease.
• In adults it may develop into more serious condition called systemic mastocytosis.

Treatment for Urticaria

a. Conventional treatment for Urticaria pigmentosa: Urticaria pigmentosa is hard to treat with the conventional medicine.

1. Oral antihistamines are useful because they reduce the mast cell’s ability to react to histamine.
2. Disodium cromoglicate orally may be helpful in some cases as they act as mast cell stabilizers.
3. Topical steroids have limited role.
4. Photo chemotherapy for longer periods may be helpful to some extent.

b. Homeopathic treatment for Urticaria pigmentosa:

1. Homeopathy works effectively for urticaria pigmentosa. Homeopathy evaluation takes into account genetic, immunological and allergic factors in particular while treating this conditions. Results are positive and encouraging. Strongly recommended.