Urticaria Pigmentosa – Causes, Symptoms, Diagnosis, And Treatment
What is urticaria pigmentosa?
Urticaria pigmentosa, also called maculopapular cutaneous mastocytosis, is a skin disease that causes patches of discolored lesions and itchy skin. It is a rare disease caused by excessive numbers of mast cells in the skin. Hives can develop when these skin areas are rubbed. Urticaria pigmentosa is most common in children. It can also occur in adults.
What causes urticaria pigmentosa?
Urticaria pigmentosa occurs when there are too many inflammatory cells (mast cells) in the skin. Mast cells are immune system cells that help the body fight infections. Mast cells make and release histamine, which causes nearby tissues to become swollen and inflamed.
The following things can trigger histamine release and skin symptoms:
- Rubbing the skin
- Drinking hot liquids, eating spicy food
- Sunlight, exposure to cold
- Drugs, such as aspirin or other NSAIDs, codeine, morphine, x-ray dye, some anesthesia drugs, alcohol
What are the symptoms of urticaria pigmentosa?
The main symptom is discolored patches on the skin. These patches contain histamine. When histamine is triggered, the patches develop into hive-like bumps. Younger children may develop a blister that is filled with fluid if the bump is scratched.
In severe cases, the following symptoms may occur:
- Fainting (uncommon)
- A headache
- Rapid heartbeat
How is urticaria pigmentosa diagnosed?
The doctor will examine the skin. The doctor may suspect urticaria pigmentosa if hives (raised bumps) develop when the skin patches are rubbed. This is called the Darier sign.
The following tests are done to check for this condition:
- Skin biopsy to look for a higher number of mast cells
- Urine histamine
- Blood tests for blood cell counts and blood tryptase levels (tryptase is an enzyme found in mast cells)
How is urticaria pigmentosa treated?
Antihistamine medicines can help relieve symptoms such as itching and flushing. Your doctor may prescribe topical corticosteroids or sometimes light therapy.
Your doctor may also prescribe other kinds of medicine to treat symptoms of severe and unusual forms of urticaria pigmentosa.
This feature is for informational purposes only and is not intended to substitute the expert guidance of a doctor. We advise seeing a doctor if you have any health concerns.