Microscopic colitis (lymphocytic colitis and collagenous colitis)
Overview
Microscopic colitis is a chronic inflammatory disease of the large intestine (colon) that commonly causes persistent or recurrent, non-bloody watery diarrhea. Unlike inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis, the colon usually appears normal during a colonoscopy. Instead, the inflammation can only be seen under a microscope after a biopsy, which is how the condition gets its name.
There are two main types of microscopic colitis: lymphocytic colitis and collagenous colitis.
Lymphocytic colitis is characterized by an increased number of lymphocytes (a type of white blood cell) in the lining of the colon, while collagenous colitis is distinguished by a thickened layer of collagen beneath the lining of the colon. Although the two subtypes have distinct microscopic features, they typically cause similar symptoms and are treated similarly.
While experts do not classify lymphocytic colitis as a classic autoimmune disease because it lacks specific autoantibodies, it is widely considered an immune-mediated disorder.
Common Symptoms
Chronic watery diarrhea, abdominal pain or cramping, urgency to have a bowel movement, frequent bowel movements, nighttime diarrhea, fecal incontinence, bloating, nausea, fatigue, dehydration, and unintended weight loss.
Coexisting Diseases and Conditions
Conditions commonly associated with microscopic colitis include celiac disease, autoimmune thyroid disease, rheumatoid arthritis, type 1 diabetes, Sjögren disease, psoriasis, inflammatory bowel disease, and bile acid malabsorption.
Risk Factors and Prevalence
Most commonly affects adults over the age of 60 and is more common in females than males, particularly collagenous colitis. Smoking has been associated with an increased risk, especially for lymphocytic colitis. Certain medications, including proton pump inhibitors (PPIs), nonsteroidal anti-inflammatory drugs (NSAIDs), selective serotonin reuptake inhibitors (SSRIs), and some statins, have also been linked to the condition. People with other autoimmune diseases, particularly celiac disease and autoimmune thyroid disease, have an increased risk of developing microscopic colitis.
Sources
- Sources
Miehlke, S., Verhaegh, B., Tontini, G. E., Madisch, A., Langner, C., & Münch, A. (2019). Microscopic colitis: pathophysiology and clinical management. The lancet. Gastroenterology & hepatology, 4(4), 305–314. https://doi.org/10.1016/S2468-1253(19)30048-2
Tome, J., Kamboj, A. K., & Pardi, D. S. (2021). Microscopic Colitis: A Concise Review for Clinicians. Mayo Clinic proceedings, 96(5), 1302–1308. https://doi.org/10.1016/j.mayocp.2021.03.022
Lazenby A. J. (2005). Collagenous and lymphocytic colitis. Seminars in diagnostic pathology, 22(4), 295–300. https://doi.org/10.1053/j.semdp.2006.04.006
Jawhari, A., & Talbot, I. C. (1996). Microscopic, lymphocytic and collagenous colitis. Histopathology, 29(2), 101–110. https://doi.org/10.1046/j.1365-2559.1996.d01-498.x
Villanueva, M. S., & Alimi, Y. (2015). Microscopic colitis (lymphocytic and collagenous), eosinophilic colitis, and celiac disease. Clinics in colon and rectal surgery, 28(2), 118–126. https://doi.org/10.1055/s-0035-1549365
Burke, K. E., D’Amato, M., Ng, S. C., Pardi, D. S., Ludvigsson, J. F., & Khalili, H. (2021). Microscopic colitis. Nature reviews. Disease primers, 7(1), 39. https://doi.org/10.1038/s41572-021-00273-2
Fărcaş, R. A., Grad, S., & Dumitraşcu, D. L. (2022). Microscopic colitis: an update. Medicine and pharmacy reports, 95(4), 370–376. https://doi.org/10.15386/mpr-2389
Tulassay, Z., Mihaly, E., & Herszényi, L. (2020). Microscopic Colitis: A Challenging Disorder. Digestive diseases (Basel, Switzerland), 38(2), 117–121. https://doi.org/10.1159/000505263