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Mastocytosis - systemeic and diffuse

What is Mastocytosis?

Mastocytosis is a disorder characterized by mast cell proliferation and accumulation within various organs, most commonly the skin. Types of cutaneous mastocytosis include solitary mastocytoma (M), diffuse erythrodermic mastocytosis, paucicellular mastocytosis, and urticaria pigmentosa . Urticaria pigmentosa is the most common form and is characterized by oval or round red-brown macules, papules, or plaques ranging in number from a few to thousands.

Most patients with mastocytosis are children (75% of cases occur during infancy or early childhood). Incidence peaks again in patients aged 30-49 years.

What are Mast Cells?

Mast cells seem to have other roles as well. Because they gather together around wounds, mast cells may play a part in wound healing. For example, the typical itching you feel around a healing scab may be caused by histamine released by mast cells. Researchers also think mast cells may have a role in the growth of blood vessels. No one with too few or no mast cells has been found, which indicates to some scientists that we may not be able to survive with too few mast cells. The presence of too many mast cells, or mastocytosis, can occur in two forms - cutaneous (skin) and systemic (involves internal body organs). Cutaneous mastocytosis (CM), the most common form, occurs when mast cells increase in the skin. It is also called urticaria pigmentosa. CM mostly affects children.

What are the causes of mastocytosis? - systemeic and diffuse

Mastocytosis probably is a hyperplastic response to an abnormal stimulus. We don't know why some people have too many mast cells. We do know some things that trigger the release of histamine from mast cells and cause the symptoms of mastocytosis. Symptoms may be triggered by cold or heat, certain medicines, emotional stress and insect bites. The triggers aren't the same in every person.

Systemic mastocytosis is caused when mast cells collect in the tissues and can affect organs such as the liver, spleen, lymph nodes, and bone marrow.

What are the symptoms of mastocytosis?

Chemicals released by mast cells cause changes in the immune system leading to typical allergy symptoms such as itching, abdominal cramping, and even anaphylaxis (dangerously low blood pressure).

The symptoms are different, depending on where the extra mast cells are. When too many mast cells exist in a person's body, the additional chemicals can cause

• Bone or muscle pain
• Abdominal discomfort
• Nausea and vomiting
• Stomach ulcers
• Diarrhea
• Skin lesions
• Episodes of very low blood pressure and faintness
• Shock

How is mastocytosis diagnosed? - systemeic and diffuse

Doctors can diagnose urticaria pigmentosa by seeing the characteristic lesions which are dark-brown and fixed. A small skin sample may help confirm the diagnosis.

By taking a tiny piece of tissue from a different organ, such as the bone marrow, the doctor can diagnose systemic mastocytosis. Using special techniques on a bone marrow sample, the doctor looks for an increase in mast cells. Another sign of this disorder is high levels of certain mast-cell chemicals and proteins in a person's blood and sometimes in the urine.

How is mastocytosis treated? -systemeic and diffuse

Therapy is conservative and aimed at symptom relief because the prognosis for most patients with mastocytosis is excellent. None of the currently available therapeutic measures induces permanent involution of cutaneous or visceral lesions. Advise patients to avoid agents that precipitate mediator release, such as aspirin, NSAIDs, codeine, morphine, alcohol, thiamine, quinine, opiates, gallamine, decamethonium, procaine, radiographic dyes, dextran, polymyxin B, scopolamine, and D-tubocurarine. Several medicines help treat the symptoms of mastocytosis.

• Antihistamines to work against mast cell chemicals
• Medicines to relieve cramping in the intestines

Medicines help treat other signs and symptoms of mastocytosis, including Itching and other skin reactions

• Ulcer-like symptoms
• Low blood pressure
• Inability to take up nutrients from food

In rare cases in which mastocytosis is cancerous or associated with a blood disorder, the patient may have to use steroids and/or chemotherapy.

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