Mastocytosis (urticaria pigmentosa)

Skin | Dermatology | Mastocytosis (urticaria pigmentosa) (Disease)


Urticaria pigmentosa (also known as generalized eruption of cutaneous mastocytosis) is the most common form of cutaneous mastocytosis. It is a rare disease caused by excessive numbers of mast cells in the skin that produce hives or lesions on the skin when irritated.

Symptoms can range from very mild (flushing, hives, no treatment needed) diarrhea, tachycardia, nausea/vomiting, headache, and fainting (in severe case) to life-threatening (vascular collapse) which requires emergency treatment and hopitalization.

Causes and Risk factors

Urticaria Pigmentosa is characterized by excessive amounts of mast cells in the skin. Red or brown spots are often seen on the skin, typically around the chest and forehead. These mast cells, when irritated (e. g. by rubbing the skin, heat exposure), produce too much histamine, triggering an allergic reaction that leads to hives localized to the area of irritation, sometimes referred to as Dariers sign. Severe itching usually follows, and scratching the area only serves to further symptoms.

This disorder can occur at any age but is most often seen in children.

Diagnosis and Treatment

A skin biopsy and/or a urine test for histamine may be performed. Skin symptoms are treated with anitihistamines and over the counter steroid creams. Patients with severe reactions should have a medical alert bracelet and carry a self injectable epinephrine pen. Patients should try to avoid any triggers that cause their symptoms. Some patients have problems with general anesthesia and they should notify their provider of their condition before any medical procedure. ...