Systemic Mastocytosis
What is Systemic Mastocytosis?
Systemic mastocytosis is a rare disorder where too many mast cells accumulate in your body's tissues and organs. Mast cells are immune cells that normally help fight infections and heal wounds. They release chemicals like histamine during allergic reactions. In systemic mastocytosis, these cells build up in the bone marrow, liver, spleen, digestive tract, and other organs.
This condition happens when mast cells grow and multiply abnormally due to genetic changes. Most cases involve a mutation in the KIT gene, which controls mast cell growth. When mast cells release their chemicals in large amounts, they can cause allergic symptoms throughout the body. The condition ranges from mild forms that barely affect daily life to aggressive types that can damage organs.
Systemic mastocytosis is different from cutaneous mastocytosis, which only affects the skin. While rare, it can occur at any age but most often appears in adults. Understanding this condition helps you recognize symptoms early and get the right testing and treatment.
Symptoms
- Flushing of the skin, especially on the face and neck
- Itching or hives that come and go
- Abdominal pain, nausea, or diarrhea
- Bone pain or unexplained fractures
- Headaches or brain fog
- Rapid heartbeat or low blood pressure
- Enlarged liver or spleen
- Fatigue or weakness
- Episodes of severe allergic reactions
- Weight loss in aggressive forms
Some people with systemic mastocytosis have mild symptoms that only appear occasionally. Others may have no symptoms for years and only discover the condition during blood tests for other reasons. Symptoms often get worse when mast cells are triggered by certain foods, medications, temperature changes, or stress.
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Causes and risk factors
Systemic mastocytosis is caused by genetic mutations that make mast cells grow out of control. The most common mutation affects the KIT gene, which normally regulates how mast cells develop and function. This mutation is usually acquired during life, not inherited from parents. When this gene changes, it signals mast cells to keep dividing when they should stop. The exact reason why these mutations happen remains unknown in most cases.
Risk factors are not well understood because the condition is rare and appears random. It affects men and women equally. Unlike some conditions, lifestyle factors do not appear to cause systemic mastocytosis. However, certain triggers can make symptoms worse once you have the condition. These include alcohol, hot temperatures, spicy foods, insect stings, certain medications, and physical or emotional stress. Identifying your personal triggers helps you manage symptoms better.
How it's diagnosed
Doctors diagnose systemic mastocytosis through a combination of blood tests, bone marrow biopsy, and imaging studies. Blood tests check for elevated basophils, which are white blood cells related to mast cells. Basophils may increase in systemic mastocytosis, especially in aggressive forms. Rite Aid offers blood testing that includes basophil counts as part of our panel. This can help identify abnormalities that warrant further investigation.
A bone marrow biopsy is usually needed to confirm the diagnosis. Doctors look for clusters of abnormal mast cells and test for KIT gene mutations. Blood tests for tryptase, a protein released by mast cells, are also commonly ordered. If your basophil levels are elevated or you have symptoms of systemic mastocytosis, talk to your doctor about additional testing. Early detection helps you start treatment sooner and prevent complications.
Treatment options
- Avoid known triggers like alcohol, hot baths, spicy foods, and certain medications
- Antihistamines to block histamine release and reduce flushing and itching
- Mast cell stabilizers like cromolyn sodium to prevent symptom flares
- Proton pump inhibitors or H2 blockers for stomach acid and digestive symptoms
- Leukotriene inhibitors to help with respiratory and skin symptoms
- Corticosteroids for severe inflammation or organ involvement
- Aspirin therapy in some cases to reduce flushing, but only under doctor guidance
- Targeted therapy drugs like imatinib or midostaurin for aggressive disease
- Epinephrine auto-injector to carry for severe allergic reactions
- Regular monitoring through blood tests and doctor visits
Concerned about Systemic Mastocytosis? Get tested at Rite Aid.
- Simple blood draw at your nearest lab
- Results in days, not weeks
- Share results with your doctor
Frequently asked questions
The first signs often include skin flushing, itching, and digestive problems like diarrhea or abdominal pain. Some people notice unexplained allergic reactions or hives. Many patients experience bone pain or headaches that come and go. Early symptoms can be mild and easy to mistake for allergies or other common conditions.
Blood tests can show signs that suggest systemic mastocytosis, such as elevated basophil levels. Doctors also order tryptase blood tests, which measure a protein released by mast cells. While blood tests provide important clues, a bone marrow biopsy is usually needed to confirm the diagnosis. Regular blood testing helps monitor the condition once diagnosed.
The seriousness varies widely depending on the type. Indolent systemic mastocytosis is the most common form and progresses slowly with manageable symptoms. Aggressive systemic mastocytosis can damage organs and requires intensive treatment. Most people with the condition can live normal lives with proper management and monitoring.
Common triggers include alcohol, extreme temperatures, spicy foods, insect stings, and physical or emotional stress. Certain medications like aspirin, NSAIDs, and some anesthetics can also cause flares. Infections and vigorous exercise may trigger symptoms in some people. Each person has different triggers, so tracking your symptoms helps identify what to avoid.
There is currently no cure for most forms of systemic mastocytosis. Treatment focuses on managing symptoms and preventing complications. In rare aggressive cases, stem cell transplantation may be considered. Most people manage well with medications and lifestyle adjustments that reduce mast cell activation.
Systemic mastocytosis involves abnormal growth and buildup of mast cells in organs, while allergies are normal mast cell responses to allergens. People with systemic mastocytosis may have allergy-like symptoms without exposure to specific allergens. The symptoms tend to be more unpredictable and can be more severe. Blood tests and bone marrow examination help distinguish between the two.
Many people benefit from avoiding alcohol, spicy foods, aged cheeses, fermented foods, and foods high in histamine. Shellfish, nuts, and foods with artificial additives may trigger symptoms in some patients. Keeping a food diary helps you identify your personal triggers. Work with a nutritionist familiar with mast cell disorders to create a personalized eating plan.
Most doctors recommend blood tests every 3 to 6 months to monitor basophil counts and overall health. Tryptase levels may be checked regularly to track disease activity. Your doctor may order additional tests if symptoms worsen or new symptoms appear. Regular monitoring helps catch changes early and adjust treatment as needed.
Yes, people with systemic mastocytosis have a higher risk of severe allergic reactions including anaphylaxis. This can happen even without exposure to typical allergens. Most doctors recommend carrying an epinephrine auto-injector at all times. Wearing a medical alert bracelet helps emergency responders provide appropriate care if a severe reaction occurs.
The genetic mutations that cause systemic mastocytosis are usually acquired during life, not inherited from parents. Most cases occur sporadically without family history. Rare familial forms do exist but are extremely uncommon. Children of people with systemic mastocytosis typically do not inherit the condition.