National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Mastocytic enterocolitis


Mastocytic enterocolitis is a term describing the condition of chronic, intractable diarrhea in people with normal colon or duodenum biopsy results, but with an increased number of mast cells in the mucosa (the innermost layer of the colon).[1] The increase in mast cells is not associated with systemic mastocytosis or cutaneous mastocytosis.[2] The infiltration of mast cells is thought to be a reactive, gut-specific phenomenon from unknown stimuli.[3] It is unclear whether the accumulation of mast cells causes, or is a response to, the inflammation that causes the symptoms.[1] Most people with this condition respond well to treatment, which may involve medications such as cetirizine, ranitidine, cromolyn sodium, or corticosteroids.[3][2]
Last updated: 8/3/2017
Signs and symptoms of mastocytic enterocolitis primarily include chronic, intractable diarrhea and abdominal pain. Other symptoms that have occasionally been reported include constipation, nausea, and/or vomiting.[2][4]
Last updated: 10/25/2016
Mastocytic enterocolitis may be considered when a person has intractable diarrhea, and other causes have been ruled out, including systemic mastocytosis.[4] It is diagnosed after an endoscopic procedure in which the doctor takes samples of tissues (biopsies) from the lining of the intestines. The tissue is then sent to a pathologist who looks at it under the microscope. Mastocytic enterocolitis is diagnosed when excess mast cells are present in the small bowel or the colon.[2]
Last updated: 8/3/2017
There is limited information in the medical literature about the treatment of mastocytic enterocolitis. Most people with this condition respond well when treated with medications such as cetirizine, ranitidine, and/or cromolyn sodium. Glucocorticoids also decrease mast cell concentration in affected tissues.[3]
Last updated: 8/3/2017

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

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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 Centers for Disease Control and Prevention (CDC) provides information on chronic diarrhea. The CDC is recognized as the lead federal agency for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of the people of the United States.

In-Depth Information

  • 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.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Mastocytic enterocolitis. Click on the link to view a sample search on this topic.

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  1. Ogilvie-McDaniel C, Blaiss M, Osborn FD, Carpenter J. Mastocytic enterocolitis: a newly described mast cell entity. Ann Allergy Asthma Immunol. December 2008; 101(6):645-646.
  2. Jakate S, Demeo M, John R, Tobin M, Keshavarzian A.. Mastocytic enterocolitis: increased mucosal mast cells in chronic intractable diarrhea. Arch Pathol Lab Med. March 2006; http://www.ncbi.nlm.nih.gov/pubmed/16519565.
  3. Capannolo A, Viscido A, Sollima L et al. Mastocytic enterocolitis: Increase of mast cells in the gastrointestinal tract of patients with chronic diarrhea. Gastroenterol Hepatol. July 16, 2016; https://www.ncbi.nlm.nih.gov/pubmed/27436817.
  4. Seo H, Park SH, Jeong-Sik B et al. Chronic intractable diarrhea caused by gastrointestinal mastocytosis. Intestinal Research. July 2016; 14(3):https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4945533/.