Hives are as well known as urticaria, welts, wheals, or nettle rash. It is a red, elevated, itchy skin rash that is occasionally triggered by something that produces an allergic reaction - an allergen. The body discharges a protein called histamine when there is an allergic reaction. Once histamine is released our capillaries (tiny blood vessels) leak fluid. The fluid collects in the skin and causes a rash.

According to Medilexicon’s medical dictionary, urticaria is “An eruption of itching wheals, colloquially called hives, usually of systemic origin; it may be due to a state of hypersensitivity to foods or drugs, focus of infection, physical agents (heat, cold, light, friction), or psychic stimuli.”

Urticaria can be triggered by:

• Certain foods.
• Insect bites and stings.
• Irritant, such as nettles, chemicals contact.
• Certain medications - such as NSAIDs (nonsteroidal anti-inflammatory drugs), used to treat pain, ACE inhibitors, used to treat hypertension (high blood pressure).
• Temperatures extremes.
• Sunlight.
• Water on the skin.

Specialists say that in about half of all cases of urticaria the cause is not ever found. About 1 in every 6 people suffers from urticaria at some time in their life. Children and women are more normally affected than adult men. Urticaria is not infectious - you cannot pass it on to another person.

Acute urticaria or acute hives

It is called acute urticaria when symptoms last less than 6 weeks. This is by far the most common type. 25% of people with acute urticaria also have angioedema - deeper layers of skin swelling.

Chronic urticaria or Chronic hives

If urticaria symptoms remain for more than six weeks it is called chronic urticaria. Dermatologists say that around 1 in every 1,000 people suffer from chronic urticaria. Specialists are not entirely certain that what the chronic urticaria causes are. Still, most approve that it is narrowly related with our immune system. In some cases, chronic hives may be associated to a basic autoimmune disorder, such as thyroid disease or lupus. 50% of people with chronic urticaria also have angioedema.

Angioedema is alike urticaria, nevertheless happens deeper inside the skin. The swelling causes a burning feeling and normally happens on the face and neck, fingers, toes, and in the male genitals.

Symptoms

As a rash, swellings, known as wheals, appear on the skin. They are generally pink or red and have an oval or round shape, and range from a few millimeters in diameter to a several inches. They can be awfully itchy. The wheals may be bounded by a red flare.

The wheals typically ensue in sets, and often appear on the face or the extremities (arms, hands, fingers, legs, feet, and toes).

A welt will vanish after a few hours, in maximum circumstances, but be replaced by new ones. They can appear on just one part of the body, or several parts.

Symptoms exist for no more than 8 to 12 hours, in the majority of cases, and seldom last for further 24 hours. Yet, with some patients the problems may stay for rather a few days, and even several months.

Anaphylaxis

Anaphylaxis is a severe allergic reaction. The patient can have severe breathing problems, and can even lose consciousness and die if not treated fast. The allergic reaction may include the whole body. It is a medical emergency. If somebody has urticaria, it is essential to be aware for added symptoms which could show an anaphylaxis reaction.

Anyone who experiences the symptoms listed below ought to call the emergency services instantly:

• Nausea and vomiting.
• Mouth lining, tongue, lips and throat swelling; causing breathing strain.
• Cold and clammy skin.
• Speedy heartbeat.
• Feeling faint or dizzy.
• An unpredictable sudden strong anxiety feeling.

Causes

Specialists say that urticaria ensues when the body releases histamine and other chemicals from under the skin surface. The histamine and chemicals cause inflammation and fluid to collect under the skin, causing wheals. In about 50% of all acute urticaria cases, the trigger is unidentified.

The subsequent are examples of some recognized triggers:

• Medications - comprising NSAIDs, such as aspirin and antibiotics.
• Foods - some diverse foods types have been identified to trigger urticaria. The most common ones are nuts, chocolate, some citrus fruits, shellfish, food additives, eggs, and wheat products.
• Infections - comprising influenza, the common cold, glandular fever and hepatitis B.
• War zones - In the war history, dermatologic diseases have been liable for troop sickness, poor confidence and battle futility. Dermatitis, nonthreatening moles, hives and cancerous skin lesions are amongst the most common diagnoses between military people who were evacuated from battle areas for ill-defined dermatologic diseases, a study exposed.
• Intestinal parasites.
• Temperature extremes.
• Certain pets.
• Dust mites.
• Sunlight exposure (less common).
• Insect bites.
• Some chemicals.
• Chronic illness - such as thyroid disease or lupus.

Chronic urticaria (long term urticaria), on the other hand, is barely ever instigated by these triggers. Chronic urticaria normally starts as an autoimmune response in which certain cells (mast cells) cause the histamine release and several chemicals to be released beneath the skin, causing tiny blood vessels to leak, which results in swelling and wheals. Specialists do not know why this occurs.

Diagnosis

Acute urticaria diagnosis

A doctor can simply diagnose acute urticaria by examining the skin rash. The doctor will try to find out what the trigger was; as this can aid the patient prevent reappearances.

Normally, the doctor will ask the patient the subsequent questions:

• When the incident initiated.
• Whether the patient lives or works in a place where latent triggers might exist, such as chemicals, or animals.
• What medications the patient has been taking, plus herbal supplements.
• Medical history of the patient.
• Whether the patient had been insect bitten.
• Whether any near relatives also have/had urticaria.

The doctor and patient will never find out what the trigger was in half of all circumstances. Still, most cases will resolve themselves within a few days and never return.

Chronic urticaria diagnosis:

If the urticaria remains for more than six weeks the probability of there being some external trigger is very small; which is why allergy tests are not recommended. Yet, the doctor will be intent in factors which may worsen the current urticaria, such as alcohol, caffeine consumption, mental health (stress), etc.

If there are any core causes for the chronic urticaria, the doctor may order the following tests:

• A blood test to find out whether the patient is anemic.
• A stool sample to check for parasites.
• ESR (erythrocyte sedimentation rate) test - this can find the patient’s immune system complications.
• Thyroid function test - this detects any hyperthyroidism (overactive thyroid) or hypothyroidism (underactive thyroid).
• Liver function tests - these can find whether the patient has any liver problems.