What is Urticaria Pigmentosa?

Urticaria pigmentosa is a type of skin disease that is often characterized by the development of skin lesions and itching. This is a type of mastocytosis, a condition that leads to the development of too many inflammatory cells, known as mast cells. Though anyone can develop urticaria pigmentosa, this condition is seen primarily in children. Treatment for urticaria pigmentosa usually involves the use of over-the-counter or prescription antihistamines, though other medications may become necessary in severe cases.

The most common characteristic of urticaria pigmentosa is the presence of lesions or bumps that tend to have a brown color. If the skin is rubbed, the area will often develop bumps that resemble hives. Fluid-filled blisters may develop as well, especially in young children who scratch the itchy lesions. In many cases, the face may become flushed when there is an outbreak of urticaria pigmentosa.

Though uncommon, more serious symptoms may develop in people with severe urticaria pigmentosa. These symptoms may include headache and diarrhea. Some people may develop a rapid heartbeat, known as tachycardia. In rare cases, fainting also may occur. These symptoms should immediately be reported to a doctor to ensure more serious side effects do not develop.

Tests that are often used to accurately diagnose urticaria pigmentosa typically include a skin test or a urine test. The skin test is performed to detect the presence of an abnormal number of mast cells. The urine test is used to measure the amount of histamine present. Histamine is a chemical found in the body that is responsible for regulating the immune system's responses to allergens.

In most cases, urticaria pigmentosa goes away on its own by the time the patient reaches puberty. In other cases, the disease slowly gets better as the patient ages. In rare instances, this condition affects adults and can turn into a more serious medical condition. Monitoring by a physician is typically recommended.

Certain medications have been shown to trigger flare-ups of this skin condition in some patients. A doctor should be consulted right away if this is suspected. People who have urticaria pigmentosa also have a greater risk of developing an allergic reaction to a bee sting. For this reason, many doctors will prescribe an injectable medication called epinephrine to be used if adverse reactions are experienced following a bee sting. If this medication has to be used, it is still advised to seek medical attention right away.