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Living with Mastocytosis

A condition in which too many mast cells (immune cells) build up in the skin or organs.

Understanding Mastocytosis

Mastocytosis occurs when too many mast cells build up in the skin or internal organs such as the liver, spleen, bone marrow, and small intestines.

Mast cells are white blood cells that help protect against infection and cause inflammation. Symptoms depend on which parts of the body are affected. Cutaneous mastocytosis affects only the skin and is more common in children. Systemic mastocytosis affects more than one body part and is more common in adults.

Signs & symptoms

GARD doesn't list specific symptoms for this condition yet.

Not everyone has every symptom. GARD's list comes from the Human Phenotype Ontology.

Diagnosis

  1. Talk with your doctor

    Share the symptoms you've noticed, when they started and your family health history. Notes and photos can help.

  2. See a specialist

    Specialists who may be involved include blood and bone marrow specialists and cancer specialists.

  3. Ask which tests can help

    Your care team will decide which exams and tests can confirm the diagnosis.

  4. Connect with expert centers

    The Mast Cell Disease Society may keep lists of experts for this condition.

Care & treatment

Care team
Blood and bone marrow specialists (hematologists); Cancer specialists (oncologists)
Expert care
Expert lists: The Mast Cell Disease Society
Treatment
GARD doesn't list specific treatments for this condition. Your care team will tailor care to your symptoms.
Research
Clinical trials and observational studies may be options. See the research section below.

General information, not medical advice. Your care team makes the decisions.

Everyday life

Living with a rare condition is easier with support.

  • Connect with The Mast Cell Disease Society and other patient organizations
  • Keep notes on symptoms, changes and questions for appointments
  • Ask about patient registries that help research
  • Look into financial aid and travel resources for care visits
Bring these questions to your next doctor visit
Do I have cutaneous or systemic mastocytosis?
Would a skin or bone marrow biopsy help confirm this?
Which specialists should manage my care?

Quick facts

Symptoms usually startany time in life

It is usually caused by changes in the KIT gene. Most are somatic changes, which occur only in certain parts of the body and are not inherited. Rarely it affects more than one person in a family.

Blood

Also known as: mast cell disease; mast cell hyperplasia

Patient organizations

Source: NIH GARD · MastocytosisGARD ID 6987 · GARD page updated September 2026 · Plain-language summary by Know Rare; editorial review pending. General information, not medical advice.

You are more than your diagnosis

Perspectives from people navigating life with Mastocytosis.

Explore the Mastocytosis blog

Explore research for Mastocytosis

Explore actively recruiting Mastocytosis studies with HealthSpark.

HealthSpark

Find actively recruiting studies for Mastocytosis with HealthSpark. Share your city to explore research near you.

  • Recruiting studies from ClinicalTrials.gov
  • Share your city to look for research near you
  • Eligibility is confirmed by the study team

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Powered by HealthSpark, our AI chat helper · Study information from ClinicalTrials.gov · Eligibility is confirmed by the study team.

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