Mastocytosis

Title

Other Names:

Mast cell disease

Summary Summary

Mastocytosis is a condition that occurs when mast cells accumulate in skin and/or internal organs such as the liver, spleen, bone marrow, and small intestines. The signs and symptoms vary based on which part(s) of the body are affected. There are two main forms of mastocytosis: cutaneous and systemic. Cutaneous mastocytosis only affects the skin and is usually diagnosed in children. Systemic mastocytosis affects more than one part of the body and is usually diagnosed in adults.^[1]^[2] It is usually caused by changes (mutations) in the KIT gene. Most cases are caused by somatic mutations which are not inherited or passed on to the next generation; however, it can rarely affect more than one family member.^[3]^[4] Treatment is based on the signs and symptoms present in each person.^[5]

For more specific information regarding the symptoms, diagnosis, treatment and/or prognosis of systemic mastocytosis and cutaneous mastocytosis, please click on the link.

Last updated: 6/18/2015

Symptoms Symptoms

The Human Phenotype Ontology (HPO) provides the following list of features that have been reported in people with this condition. Much of the information in the HPO comes from Orphanet, a European rare disease database. If available, the list includes a rough estimate of how common a feature is (its frequency). Frequencies are based on a specific study and may not be representative of all studies. You can use the MedlinePlus Medical Dictionary for definitions of the terms below.

Signs and Symptoms	Approximate number of patients (when available)
Abnormality of skin pigmentation	Very frequent (present in 80%-99% of cases)
Macule	Very frequent (present in 80%-99% of cases)
Mastocytosis	Very frequent (present in 80%-99% of cases)
Pruritus	Very frequent (present in 80%-99% of cases)
Urticaria	Very frequent (present in 80%-99% of cases)
Abnormal blistering of the skin	Frequent (present in 30%-79% of cases)
Diarrhea	Frequent (present in 30%-79% of cases)
Impaired temperature sensation	Frequent (present in 30%-79% of cases)
Nausea and vomiting	Frequent (present in 30%-79% of cases)
Acute leukemia	Occasional (present in 5%-29% of cases)
Angioedema	Occasional (present in 5%-29% of cases)
Anorexia	Occasional (present in 5%-29% of cases)
Arrhythmia	Occasional (present in 5%-29% of cases)
Asthma	Occasional (present in 5%-29% of cases)
Chronic leukemia	Occasional (present in 5%-29% of cases)
Cough	Occasional (present in 5%-29% of cases)
Fatigue	Occasional (present in 5%-29% of cases)
Gastrointestinal hemorrhage	Occasional (present in 5%-29% of cases)
Hepatomegaly	Occasional (present in 5%-29% of cases)
Hypercalcemia	Occasional (present in 5%-29% of cases)
Hypotension	Occasional (present in 5%-29% of cases)
Osteoporosis	Occasional (present in 5%-29% of cases)
Recurrent fractures	Occasional (present in 5%-29% of cases)
Respiratory insufficiency	Occasional (present in 5%-29% of cases)
Sarcoma	Occasional (present in 5%-29% of cases)
Splenomegaly	Occasional (present in 5%-29% of cases)
Telangiectasia of the skin	Occasional (present in 5%-29% of cases)
Autosomal dominant inheritance	-
Cutaneous mastocytosis	-
Erythema	-
Hypermelanotic macule	-
Telangiectasia macularis eruptiva perstans	-

Last updated: 7/1/2017

Cause Cause

Most cases of mastocytosis are caused by changes (mutations) in the KIT gene. This gene encodes a protein that helps control many important cellular processes such as cell growth and division; survival; and movement. This protein is also important for the development of certain types of cells, including mast cells (immune cells that are important for the inflammatory response). Certain mutations in the KIT gene can leads to an overproduction of mast cells. In mastocytosis, excess mast cells accumulate in the skin and/or internal organs, leading to the many signs and symptoms of the condition.^[5]^[6]

Last updated: 6/18/2015

Inheritance Inheritance

Most cases of mastocytosis are not inherited. They occur spontaneously in families with no history of the condition and are due to somatic changes (mutations) in the KIT gene. Somatic mutations occur after conception and are only present in certain cells. Because they are not present in the germ cells (egg and sperm), they are not passed on to the next generation.^[2]^[5]

Mastocytosis can rarely affect more than one family member. In some of these cases, the condition is inherited in an autosomal dominant manner.^[3]^[4] This means that to be affected, a person only needs a change (mutation) in one copy of the responsible gene in each cell. A person with familial mastocytosis has a 50% chance with each pregnancy of passing along the altered gene to his or her child.

Last updated: 6/18/2015

Diagnosis Diagnosis

Mastocytosis is often first suspected by a doctor due to the symptoms present. The diagnosis may be confirmed by a skin biopsy. During a skin biopsy, a sample of skin tissue is taken and looked at under a microscope for the presence of dense areas of mast cells. In some cases, a bone marrow biopsy may be performed.^[7]

If the diagnosis is uncertain, blood and/or urine tests may be used to measure the levels of specific chemicals or substances related to mast cells. High levels of certain substances support the diagnosis of mastocytosis. Some substances may be elevated in systemic mastocytosis, but not in cutaneous mastocytosis. Other evaluations or tests used to confirm a diagnosis may include a bone scan, gastrointestinal workup, and/or genetic testing.^[7]

Additional tests may be ordered to rule out conditions that may cause similar symptoms, such as anaphylaxis, pheochromocytoma, carcinoid syndrome, or Zollinger-Ellison syndrome.^[7]

Last updated: 11/18/2015

Testing Resources

The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Treatment Treatment

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.

Cromolyn sodium (Brand name: Gastrocrom® (oral)) - Manufactured by Azur Pharma
FDA-approved indication: Treatment of mastocytosis.
National Library of Medicine Drug Information Portal
Midostaurin (Brand name: Rydapt) - Manufactured by Novartis Oncology
FDA-approved indication: Treatment of adult patients with aggressive systemic mastocytosis (ASM), systemic mastocytosis with associated hematological neoplasm (SM-AHN), or mast cell leukemia (MCL).
National Library of Medicine Drug Information Portal

Statistics Statistics

Mastocytosis is described as a rare disorder, but to our knowledge, the exact incidence and prevalence are not known.^[1] A disorder is considered rare if it affects fewer than 200,000 people in the United States at any given time. An estimate of prevalence from a recent population-based study is approximately 1 case per 10,000 people.^[8]

While mastocytosis in general affects males and females in equal ratios, there appears to be a slight male predominance in childhood and a slight female predominance in adulthood. In children, 80% of cases appear during the first year of life, and the majority is limited to the skin. Adults who develop mastocytosis more often have systemic forms of the disease. Cutaneous forms of the disease account for less than 5% of adult cases.^[1]

Last updated: 11/18/2015

Do you have updated information on this condition? Let us know.

Research Research

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

ClinicalTrials.gov lists trials that are studying or have studied Mastocytosis. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.
The Research Portfolio Online Reporting Tool (RePORT) provides access to reports, data, and analyses of research activities at the National Institutes of Health (NIH), including information on NIH expenditures and the results of NIH-supported research. Although these projects may not conduct studies on humans, you may want to contact the investigators to learn more. To search for studies, enter the disease name in the "Text Search" box. Then click "Submit Query".

Organizations Organizations

Nonprofit support and advocacy groups bring together patients, families, medical professionals, and researchers. These groups often raise awareness, provide support, and develop patient-centered information. Many are the driving force behind research for better treatments and possible cures. They can direct people to research, resources, and services. Many groups also have experts who serve as medical advisors. Visit their website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

The Mastocytosis Society
P.O. Box 129
Hastings, NE 68902-0129
E-mail: http://www.tmsforacure.org/contact.php
Website: http://www.tmsforacure.org/

Social Networking Websites

RareConnect has an online community for patients and families with this condition so they can connect with others and share their experiences living with a rare disease. The project is a joint collaboration between EURORDIS (European Rare Disease Organisation) and NORD (National Organization for Rare Disorders).

Do you know of an organization? Send us your suggestions.

Living With Living With

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Healthcare Resources

The Mastocytosis Society has a listing of Medical Research Centers that specialize in mastocytosis. Click on the link to view this list which includes centers in the United States and Europe.

Genetics Resources

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by GeneTests, the American College of Medical Genetics, and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference.

Learn More Learn More

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

The Merck Manuals Online Medical Library provides information on this condition for patients and caregivers.
The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
The Merck Manual for health care professionals provides information on Mastocytosis.
The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
PubMed is a searchable database of medical literature and lists journal articles that discuss Mastocytosis. Click on the link to view a sample search on this topic.

Related Diseases Related Diseases

The following diseases are related to Mastocytosis. If you have a question about any of these diseases, you can contact GARD.

GARD Answers GARD Answers

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

I am wondering about the estimated number of people having been diagnosed with this disease. I have it, but have not been diagnosed yet. See answer
Is mastocytosis contagious? See answer
Is mastocytosis hereditary? See answer

Have a question? Contact a GARD Information Specialist.

References References

Castells MC and AKin C. Mastocytosis (cutaneous and systemic): Epidemiology, pathogenesis, and clinical manifestations. UpToDate. November 13 2015; http://www.uptodate.com/contents/mastocytosis-cutaneous-and-systemic-epidemiology-pathogenesis-and-clinical-manifestations.
Mastocytosis. NORD. April 2014; http://www.rarediseases.org/rare-disease-information/rare-diseases/byID/441/viewAbstract.
Fett NM, Teng J, Longley BJ. Familial urticaria pigmentosa: report of a family and review of the role of KIT mutations. Am J Dermatopathol. February 2013; 35(1):113-116. https://www.ncbi.nlm.nih.gov/pubmed/22892471.
de Melo Campos P, Machado-Neto JA, Scopim-Ribeiro R, Visconte V, Tabarroki A, Duarte AS, Barra FF, Vassalo J, Rogers HJ, Lorand-Metze I, Tiu RV, Costa FF, Olalla Saad ST, Traina F. Familial systemic mastocytosis with germline KIT K509I mutation is sensitive to treatment with imatinib, dasatinib and PKC412. Leuk Res. October 2014; 38(10):1245-1251. https://www.ncbi.nlm.nih.gov/pubmed/25139846.
Daniel J Hogan, MD. Mastocytosis. Medscape Reference. February 2015; http://emedicine.medscape.com/article/1057932-overview.
KIT. Genetics Home Reference. September 2014; http://ghr.nlm.nih.gov/gene/KIT.
Peter J. Delves. Mastocytosis. Merck Manual. March, 2014; http://www.merckmanuals.com/professional/immunology-allergic-disorders/allergic-autoimmune-and-other-hypersensitivity-disorders/mastocytosis.
Theoharides TC, Valent P, and Akin C. Mast Cells, Mastocytosis, and Related Disorders. N Engl J Med. July 9, 2015; 373(2):163-172. https://www.ncbi.nlm.nih.gov/pubmed/26154789.