Table of ContentsView AllTable of ContentsDefinitionIndolent Systemic MastocytosisMast Cell Activation Syndrome (MCAS)Other VariantsSymptomsTraits of Systemic Mastocytosis SymptomsDiagnosisHome RemediesTreatmentTriggersContinued Reading and Support
Table of ContentsView All
View All
Table of Contents
Definition
Indolent Systemic Mastocytosis
Mast Cell Activation Syndrome (MCAS)
Other Variants
Symptoms
Traits of Systemic Mastocytosis Symptoms
Diagnosis
Home Remedies
Treatment
Triggers
Continued Reading and Support
Systemic mastocytosis is a rare health condition in which too many mast cells (a type of immune system cell) build up in the body, causing allergic reactions and other health issues. This disorder encompasses various subtypes, each presenting unique challenges and symptoms.
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Defining Systemic Mastocytosis
Systemic mastocytosis happens when a type of white blood cell calledmast cellsbuilds up too much in the body’s tissues. These cells are made in the bone marrow, where they usually help with allergic reactions and inflammation.
In most cases of systemic mastocytosis, these mast cells have a change in a gene called KIT. The KIT gene gives instructions for making a protein that tells mast cells when to grow and divide. When the KIT gene is mutated in systemic mastocytosis, the protein switch is always stuck in the “on” position. This causes the mast cells to grow too much and gather in the bone marrow, gastrointestinal tract, lymph nodes, spleen, or liver.
When triggered, mast cells release proteins that start an immune response. This can cause symptoms like itching, flushing, stomach pain, or severe allergic reactions.
There are five subtypes of systemic mastocytosis:
Indolent systemic mastocytosis (ISM) is the most common and typically less severe form of systemic mastocytosis. In indolent systemic mastocytosis, mast cells accumulate in various organs but do not cause significant organ damage or dysfunction. Symptoms may be mild and usually include skin lesions and gastrointestinal issues. The life expectancy for people with ISM is similar to that of the general population.
The main difference is that MCAS involves the inappropriate activation of normal mast cells, causing them to release their mediators excessively and inappropriately, leading to symptoms. The number of mast cells is typically normal.
However, with systemic mastocytosis, mast cells abnormally accumulate in various tissues, including the skin, bone marrow, and internal organs. These mast cells may also behave abnormally.
Other variants of systemic mastocytosis, starting with the least severe, include:
Smoldering Systemic Mastocytosis
Aggressive Systemic Mastocytosis
ASM involves a rapid and extensive accumulation of abnormal mast cells in multiple organs, leading to severe symptoms such as organ dysfunction, bone fractures, and potentially life-threatening complications. Examples of organ dysfunction include low white blood cells, liver dysfunction, anemia, and low platelets.
ASM requires intensive treatment to manage its aggressive nature and preserve organ function.
Mast Cell Leukemia
MCL is an exceptionally rare and highly aggressive subtype in which mast cells rapidly multiply in the bone marrow and bloodstream. This results in severe symptoms such as high mast cell levels in the blood, organ failure, and a significantly reduced life expectancy.Treatment for MCL is challenging and often focuses on managing symptoms and improving quality of life.
Systemic Mastocytosis with an Associated Hematologic Neoplasm
SM-AHN is a rare subtype in which systemic mastocytosis coexists with another health condition, such asacute myeloid leukemia(AML). This combination poses diagnostic challenges and requires careful management due to the overlapping symptoms and complexities in treatment.
People with SM-AHN may experience symptoms related to both mastocytosis and other hematologic disorders, necessitating a multidisciplinary approach involving hematologists and oncologists for optimal care.
Possible Systemic Mastocytosis Symptoms
Systemic mastocytosis encompasses a spectrum of symptoms that can vary widely in severity and presentation across different people. These symptoms predominantly arise from the excessive activation and release of mast cells, affecting various organ systems in the body.
Emergency Systemic Mastocytosis Symptoms
Emergency symptoms of systemic mastocytosis can be severe and require immediate medical attention. These include:
Anaphylaxis
Hypotension
Skin and Rash Symptoms
Skin manifestations are common in systemic mastocytosis, often presenting as:
GI Symptoms
Gastrointestinal (GI) symptoms in systemic mastocytosis may include:
Other Symptoms
Systemic mastocytosis can affect various other organ systems and manifest with diverse symptoms, including:
Path to Systemic Mastocytosis Diagnosis
Your healthcare provider will gather a detailed medical history and conduct a physical examination to identify symptoms. Specialists involved in diagnosis typically include allergists, dermatologists, gastroenterologists, and hematologists. It is a good idea to keep detailed records of your symptoms so you don’t forget anything when you speak with your providers.
Askin biopsyis often the first step if cutaneous mastocytosis is suspected. A small sample of the affected skin is examined under a microscope. The number of mast cells in the sample is counted to confirm the diagnosis.
Another diagnosis method is a bone marrow biopsy. This procedure involves numbing the skin and inserting a needle into the bone to extract marrow cells. These cells are then analyzed microscopically to identify any abnormal accumulation of mast cells.
In some cases, a biopsy from other tissues, such as the gastrointestinal tract, may be necessary to make the diagnosis.
Laboratory tests are critical for confirming systemic mastocytosis, including:
Home Remedies Without a Systemic Mastocytosis Diagnosis
If you have systemic mastocytosis symptoms, seeing your provider for treatment options is essential. But in addition to your established treatment plans, you may want to ask your provider about additional alternative approaches you can take at home, such as:
Talk to your provider about other home remedies to help with your symptoms.
Treatment With a Systemic Mastocytosis Diagnosis
Once diagnosed, treatment options may include:
Systemic Mastocytosis Triggers
Mastocytosis can worsen due to triggers that prompt mast cells to release histamine and other chemicals. While triggers can vary among individuals, common ones include:
Continued Reading and Systemic Mastocytosis Support
Living with systemic mastocytosis can be challenging, but understanding the condition and connecting with supportive resources can make a significant difference. Here are some recommended avenues for further reading and support:
Summary
13 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Cancer Institute.Systemic mastocytosis.Medline Plus.Systemic macrocytosis.National Organization for Rare Disorders.Macrocytosis.Leukemia and Lymphoma Society.Mastocytosis.The Mast Cell Disease Society.Overview, diagnosis, definitions and classification.Orphanet.Smoldering systemic mastocytosis.National Cancer Institute.Mast cell leukemia.National Cancer Institute.Systemic mastocytosis with associated hematologic neoplasm.American Society of Hematology.How I treat patients with advanced systemic mastocytosis.Gangireddy M, Ciofoaia GA.Systemic mastocytosis. In: StatPearls:StatPearls Publishing; 2024Medline Plus.Anaphylaxis.American Academy of Allergy asthma and Immunology.Systemic macrocytosis.Columbia Irving Comprehensive Cancer Center.Mastocytosis.
13 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Cancer Institute.Systemic mastocytosis.Medline Plus.Systemic macrocytosis.National Organization for Rare Disorders.Macrocytosis.Leukemia and Lymphoma Society.Mastocytosis.The Mast Cell Disease Society.Overview, diagnosis, definitions and classification.Orphanet.Smoldering systemic mastocytosis.National Cancer Institute.Mast cell leukemia.National Cancer Institute.Systemic mastocytosis with associated hematologic neoplasm.American Society of Hematology.How I treat patients with advanced systemic mastocytosis.Gangireddy M, Ciofoaia GA.Systemic mastocytosis. In: StatPearls:StatPearls Publishing; 2024Medline Plus.Anaphylaxis.American Academy of Allergy asthma and Immunology.Systemic macrocytosis.Columbia Irving Comprehensive Cancer Center.Mastocytosis.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Cancer Institute.Systemic mastocytosis.Medline Plus.Systemic macrocytosis.National Organization for Rare Disorders.Macrocytosis.Leukemia and Lymphoma Society.Mastocytosis.The Mast Cell Disease Society.Overview, diagnosis, definitions and classification.Orphanet.Smoldering systemic mastocytosis.National Cancer Institute.Mast cell leukemia.National Cancer Institute.Systemic mastocytosis with associated hematologic neoplasm.American Society of Hematology.How I treat patients with advanced systemic mastocytosis.Gangireddy M, Ciofoaia GA.Systemic mastocytosis. In: StatPearls:StatPearls Publishing; 2024Medline Plus.Anaphylaxis.American Academy of Allergy asthma and Immunology.Systemic macrocytosis.Columbia Irving Comprehensive Cancer Center.Mastocytosis.
National Cancer Institute.Systemic mastocytosis.
Medline Plus.Systemic macrocytosis.
National Organization for Rare Disorders.Macrocytosis.
Leukemia and Lymphoma Society.Mastocytosis.
The Mast Cell Disease Society.Overview, diagnosis, definitions and classification.
Orphanet.Smoldering systemic mastocytosis.
National Cancer Institute.Mast cell leukemia.
National Cancer Institute.Systemic mastocytosis with associated hematologic neoplasm.
American Society of Hematology.How I treat patients with advanced systemic mastocytosis.
Gangireddy M, Ciofoaia GA.Systemic mastocytosis. In: StatPearls:StatPearls Publishing; 2024
Medline Plus.Anaphylaxis.
American Academy of Allergy asthma and Immunology.Systemic macrocytosis.
Columbia Irving Comprehensive Cancer Center.Mastocytosis.
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