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Disease Profile

Collagenous colitis

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Microscopic colitis, collagenous type


Digestive Diseases


Collagenous colitis is a type of inflammatory bowel disease that affects the colon. It is a form of microscopic colitis, which causes chronic diarrhea. It typically occurs in middle-aged adults, is more common in females than in males, and has rarely been reported in children. In all forms of microscopic colitis, the colon appears normal or almost normal on colonoscopy, but the inflammation is visible when a biopsy of the colon is examined under a microscope (hence its name).[1]

Signs and symptoms include chronic, watery, non-bloody diarrhea that may begin suddenly or worsen over time. People with this disease usually have between four and nine watery bowel movements per day, but in rare cases may have more than fifteen. Various other symptoms relating to the gastrointestinal system or other body symptoms may also be present.[1][2]

The cause of collagenous colitis is not known but it is thought to be multifactorial. This means that both genetic and environmental factors may interact to cause a person to develop the disease.[1] The extent to which genes play a role is unclear, but familial cases have been described.[1] Certain medications, such as NSAIDS and proton pump inhibitors, have been reported to cause or trigger the disease in some people. However, strong evidence directly linking these medications to the disease is still lacking.[1]

The main goal of treatment is to lessen the number of bowel movements per day and improve quality of life.[1] Treatment depends on the symptoms and severity in each person and may involve avoiding or discontinuing medications that may be associated with the disease, taking anti-diarrheal medications, budesonide, or other medications.[1][2] Surgery to remove all or part of the colon may be needed in severe cases that do not respond to other treatments.[1] In some cases, diarrhea resolves within weeks (with or without treatment), but relapses are common.[1]


The main symptom of collagenous colitis is chronic, watery, non-bloody diarrhea.[1][3][4] Diarrhea may occur gradually and worsen over time, or it may occur very suddenly.[1] People with this disease usually have between four and nine watery bowel movements per day, but in rare cases may have more than 15 bowel movements. Other signs and symptoms may include sudden urges to have a bowel movement, uncontrolled bowel movements (fecal incontinence), abdominal pain or cramping, flatulence ("passing gas"), nausea, fatigue, bloating, and weight loss.[1][4] In some cases, the disease is also associated with joint pain, arthritis, or eye inflammation (uveitis).[1]


Treatment for collagenous colitis varies depending on the symptoms and severity in each person. The main goals of treatment are to decrease the number of bowel movements per day (typically to less than 3, with no watery bowel movements) and to improve quality of life. In some cases the condition may resolve on its own (spontaneous remission), although most people continue to have ongoing or occasional diarrhea.[2] The response to different therapies differs from person to person, so more than one therapy may need to be tried (alone or in combination with others).[1][3]

Treatment options that have been tried with varying success include:[1][2]

  • Dietary changes such as a reduced-fat diet and/or eliminating foods that contain caffeine and lactose.
  • Avoiding or discontinuing medications that some people have reported triggered the disease (such as NSAIDS and proton pump inhibitors).
  • Antidiarrheal medications such as loperamide.
  • Corticosteroids such as budesonide.
  • Anti-TNF therapies such as infliximab and adalimumab.
  • Surgery to remove all or part of the colon in severe cases that to not respond to other treatment options.


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.

Organizations Supporting this Disease

    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

      In-Depth Information

      • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
      • PubMed is a searchable database of medical literature and lists journal articles that discuss Collagenous colitis. Click on the link to view a sample search on this topic.


        1. Dietrich CF. Lymphocytic and collagenous colitis (microscopic colitis): Clinical manifestations, diagnosis, and management. UpToDate. Waltham, MA: UpToDate; September 11, 2018; https://www.uptodate.com/contents/lymphocytic-and-collagenous-colitis-microscopic-colitis-clinical-manifestations-diagnosis-and-management.
        2. Microscopic Colitis: Collagenous Colitis and Lymphocytic Colitis. National Digestive Diseases Information Clearinghouse (NDDIC). June 25, 2014; https://digestive.niddk.nih.gov/ddiseases/pubs/microcolitis/index.aspx.
        3. Mahajan D, Goldblum JR, Xiao SY, Shen B, Liu X. Lymphocytic colitis and collagenous colitis: a review of clinicopathologic features and immunologic abnormalities. Adv Anat Pathol. January 2012; 19(1):28-38.
        4. Adriana Stoicescu, Gabriel Becheanu, Mona Dumbrava, Cristian Gheorghe and Mircea Diculescu. Mædica a Journal of Clinical Medicine. 2012; 7(1):3-9. https://www.maedica.org/articles/2012/1/2012_Vol7(10)_No1_pg3-9.pdf.

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