Mastocytosis

Mastocytosis is a collection of “mast cells” in the skin, giving it a bumpy appearance.

Mast cells are cells normally found around blood vessels. These cells contain chemicals, including histamine.

Histamine is a chemical that plays a big part in allergic reactions. Histamine can be released in reaction to foods or medicines or when a group of mast cells in the skin is rubbed or heated.

There are 2 main types of mastocytosis:

• Solitary mastocytoma or multiple mastocytomas: In this type of mastocytosis, there are usually yellow, orange, tan or flesh-colored bumps on the skin. These bumps can be as small as a thumbtack or bigger than the size of a quarter. They can be present at birth or develop in your baby a bit later. They are usually on the arms, neck and trunk and are usually quite harmless but can be concerning because they don’t look very pretty. The bumps can get irritated. Stroking or rubbing them will release histamine and cause the skin to become red, more raised, and sometimes itchy, like hives. Rarely, fluid-filled blisters can develop. These blisters usually go away in a few days.
• Urticaria pigmentosa: In this type of mastocytosis, there are 10s to 100s of mastocytomas. The affected areas of skin (lesions) are usually tan, red or brown. They can be flat or raised and are found anywhere on the skin. These lesions often develop during the first few weeks to months of life, but they can grow in size and number for several months to years. Rubbing the lesions will release histamine and cause a similar reaction to a solitary mastocytoma. Very rarely children have these lesions inside their body.

Solitary mastocytomas usually goes away by school-age. Urticaria pigmentosa usually goes away before or shortly after puberty.

Mastocytosis may not need to be treated. The symptoms can be treated by antihistamine medicines taken by mouth (oral) or medicines put on the skin (topical) to help your child be more comfortable. Check with your healthcare provider before giving any type of medicine to your child.

Mastocytosis can also be controlled by avoiding the allergens or “triggers”. Triggers are things that can cause mast cells to release histamine. For children with mild mastocytosis, avoiding triggers may not make as big of a difference as those with the more severe form. Even if your child’s mastocytosis is mild, avoid exposure to triggers whenever possible.

• Aspirin
• Liquid medicines that contain alcohol, like cold and cough syrups
• Narcotics, like codeine, morphine, and dextromethorphan (DM)

• Polymyxin B (an ingredient in many antibiotic ointments)

• Curare
• Scopolamine
• Decamethonium
• Reserpine

If your child is having a procedure and anesthesia will be used, make sure your child’s surgeon and anesthesiologist knows this.

• Radiographic – iodine containing
• Gallamine

• Rubbing
• Heat
• Sunlight

• Shellfish, like crawfish and lobster