Understanding Urticaria: Causes, Symptoms, and Treatment

It is estimated that 20% of people have had hives in their lifetime, which has not been repeated and for which the cause is not known. In half of children with urticaria, it is accompanied by angioedema (swelling of the eyelids, lips, or ears).

Causes

Many cases of hives in children "go unresolved," meaning the trigger or cause of the rash will never be known. Plus it may never appear again. The formation of the hives is due to the release, by mast cells (a type of cell of the immune system that is in the skin) of a substance called histamine.

There are several mechanisms that can activate mast cells and, which are, the different causes of urticaria:

• Allergic: hives are mediated by IgE immunoglobulin and can be caused by: food, drugs, inhalants, latex, or insects
• Infections: many viruses, bacteria and parasites activate mast cells and cause a skin reaction in the form of hives
• Physical stimuli: exercise, cold, heat, sun, pressure…. All of them, in sensitive people, can cause the presence of hives
• Metabolic disorders: C1 inhibitory deficit, aspirin and anti-inflammatory intolerance, hereditary angioedema, serum sickness or vasculitis
• Drugs: radiological contrasts, opiates, polymyxin B, antibiotics ...
• Systemic diseases: hyperthyroidism, liver diseases, neoplasms, mastocytosis ...

Hives can be classified into:

• Acute: it is the most frequent form and the hives last less than six weeks
• Chronic: it is a rare form in children and hives outbreaks last more than six weeks

Symptoms

Typical skin lesions are the hives that can appear all over the body surface. They are pale red or pink in color and raised (touch). The characteristic thing is that they are very itchy and fleeting (they appear and disappear in hours or minutes).

In pediatrics, urticaria is usually a benign disease, but the intense itching it can interfere with a child's quality of life. In addition, the appearance of the child with very extensive hives and / or swelling of different parts of the body such as lips or eyelids can create alarm in parents.

When it affects vital structures as the larynx can endanger the life of the child. On the other hand, urticaria is the most common manifestation of anaphylaxis and can be an early sign of a severe allergic reaction, so it should be a reason for close observation.

Treatment

As the cause of hives is the secretion of histamine by mast cells, the treatment of hives is based on the administration of antihistamines. In the severe cases or that present anaphylaxis, it is necessary to administer adrenaline and hospital admission of the child. If an allergic cause is suspected, appropriate allergy tests should be performed and the food or substance that has caused the hives outbreaks should be avoided. In cases of long-term urticaria, the Pediatrician should carefully review the patient, assessing the need for other complementary examinations such as analytics, serologies and cultures.