Systemic mastocytosis (mas-to-sy-TOE-sis) is a rare disorder caused by a mutation that results in an excessive number of mast cells in your body. Mast cells normally help protect you from disease and aid in wound healing. But if you have systemic mastocytosis, excess mast cells can build up in various parts of your body.

When triggered, these mast cells release substances that can overwhelm your body. You might experience symptoms such as facial flushing, itching, a rapid heartbeat, abdominal cramps, lightheadedness or even loss of consciousness. Common triggers include alcohol, temperature changes, spicy foods and certain medications.

Systemic mastocytosis is classified into seven subtypes. The most common form progresses slowly, but there are others that develop rapidly. Mast cell leukemia and mast cell sarcoma subtypes are extremely rare forms of systemic mastocytosis.

  • Expertise and teamwork. At Mayo Clinic, doctors from a number of medical specialties work together to provide you with the best care possible. Your team may include specialists in allergic diseases, dermatology, gastroenterology, pediatrics, neurology, endocrinology, hematology and pathology.
  • Experience. Each year doctors at Mayo Clinic treat more than 60 people with systemic mastocytosis.
  • Timely care. A detailed itinerary for appointments, tests and procedures lets you make the most of your time at the clinic. Mayo Clinic technicians run all tests and labs themselves, which means tests taken in the morning can be reviewed the same afternoon. Mayo's collaborative approach means two or three days often yields the same diagnosis and care insights that could take weeks in less-coordinated institutions.
  • Care at Mayo Clinic revolves around you. At Mayo Clinic, doctors manage systemic mastocytosis by regularly monitoring your condition, then tailoring a treatment plan to help you manage your specific symptoms. Mayo Clinic doctors get to know you and your concerns completely, and explain your options in plain language.

At Mayo Clinic, we assemble a team of specialists who take the time to listen and thoroughly understand your health issues and concerns. We tailor the care you receive to your personal health care needs. You can trust our specialists to collaborate and offer you the best possible outcomes, safety and service.

Mayo Clinic is a not-for-profit medical institution that reinvests all earnings into improving medical practice, research and education. We're constantly involved in innovation and medical research, finding solutions to improve your care and quality of life. Your doctor or someone on your medical team is likely involved in research related to your condition.

Our patients tell us that the quality of their interactions, our attention to detail and the efficiency of their visits mean health care — and trusted answers — like they've never experienced.

Why Choose Mayo Clinic

What Sets Mayo Clinic Apart

Diagnosis of systemic mastocytosis can be confirmed by finding high numbers of mast cells or high levels of the substances they release in your body, such as tryptase, histamine products, leukotrienes or prostaglandins. Tests your doctor may use to confirm systemic mastocytosis include:

  • Bone marrow biopsy. This is the most common test. A small amount of your bone marrow tissue will be analyzed for increased numbers of mast cells. Your doctor will also look for specific genetic changes in your bone marrow cells.
  • Blood tests. A serum test for a mast cell enzyme called tryptase will be checked. A low number of red blood cells (anemia) or a high number of a type of white blood cells called eosinophils may indicate systemic mastocytosis.
  • Urine tests. High levels of histamine products, leukotrienes or prostaglandins in your urine may also indicate systemic mastocytosis.
  • Imaging tests. X-rays, ultrasounds and computerized tomography (CT) scans help determine the extent and stage of your condition by providing a picture of your insides, revealing possible bone or organ involvement.

Treatment for systemic mastocytosis varies depending on the type you have. Basic components of most systemic mastocytosis treatment plans include:

  • Treating and controlling symptoms. Mayo Clinic doctors will help you identify particular factors that may trigger your symptoms of systemic mastocytosis, such as certain foods, medications, insect stings or temperature changes. They will also work with you to help keep your systemic mastocytosis symptoms under control with medications, such as antihistamines, aspirin and certain drugs that will counteract the effects of the substances released by your mast cells — such as corticosteroids and leukotriene agonists. Your health care team may also teach you how to give yourself an epinephrine injection in the event you have a severe allergic response when your mast cells are triggered.
  • Regular monitoring. Your Mayo Clinic doctors will regularly collect blood and urine samples from you to monitor the status of your condition. Mayo Clinic is one of the only centers to offer a special home kit that you can use to collect blood and urine samples while you're experiencing symptoms, which gives your doctor a better picture of how systemic mastocytosis affects your body.
  • Bone density measurements. Because systemic mastocytosis can affect your bones and bone marrow, you may be at risk for bone problems, such as osteoporosis. At Mayo Clinic, bone density measurements every two years are a regular component of your treatment.

If you have the aggressive form of systemic mastocytosis, or mastocytosis associated with another blood disorder, you may be treated with chemotherapy medications, which reduce the number of mast cells. Chemotherapy treatment length varies depending on your specific condition, how well you respond to treatment and how well you tolerate it.

Mayo Clinic works with hundreds of insurance companies and is an in-network provider for millions of people. In most cases, Mayo Clinic doesn't require a physician referral. Some insurers require referrals or may have additional requirements for certain medical care. All appointments are prioritized on the basis of medical need.

Doctors trained in allergic diseases treat people with systemic mastocytosis at Mayo Clinic's campus in Arizona.

For appointments or more information, call the Central Appointment Office at 800-446-2279 (toll-free) 8 a.m. to 5 p.m. Mountain Standard Time, Monday through Friday or complete an online appointment request form.

Doctors trained in allergic diseases treat people with systemic mastocytosis at Mayo Clinic's campus in Florida.

For appointments or more information, call the Central Appointment Office at 904-953-0853 8 a.m. to 5 p.m. Eastern time, Monday through Friday or complete an online appointment request form.

Doctors trained in allergic diseases, dermatology, gastroenterology, pediatrics, neurology, endocrinology and hematology care for people with systemic mastocytosis at Mayo Clinic's campus in Minnesota.

For appointments or more information, call the Central Appointment Office at 507-538-3270 7 a.m. to 6 p.m. Central time, Monday through Friday or complete an online appointment request form.

See information on patient services at the three Mayo Clinic locations, including transportation options and lodging.

Doctors trained in allergic diseases and other disciplines conduct basic and clinical research in potential diagnostic tests and treatments for systemic mastocytosis. Staff in the Allergic Diseases Research Laboratory at the Mayo Clinic campus in Minnesota conduct research in systemic mastocytosis.


See a list of publications by Mayo authors on PubMed, a service of the National Library of Medicine.

April 29, 2015