Microscopic colitis is a form of inflammatory bowel disease in which the inner lining of the large intestine (colon) becomes inflamed, typically causing chronic diarrhea.
About Microscopic Colitis
Microscopic colitis is named for the very small changes to colon tissue brought about by this form of chronic inflammation, which can only be observed under a microscope. The symptoms of microscopic colitis reflect the major functions of the colon: absorbing water, electrolytes, and nutrients from digestive waste and pushing that waste outside your body. Inflammatory damage to the colon tissue disrupts these functions.
The exact cause of this condition is unknown. Possible causes include infections, irritation of the colon resulting from medications or improperly absorbed bile acids, or autoimmune (originating from your body’s own immune system) attacks on the colon. Microscopic colitis is unique among inflammatory bowel diseases because it is not linked to an elevated risk of colorectal cancer.
Types of Microscopic Colitis
The two types of microscopic colitis are associated with different changes to the colon tissue, but both forms of the condition are treated in the same way.
- Lymphocytic colitis: The inner lining of the colon contains an elevated number of white blood cells.
- Collagenous colitis: The collagen that surrounds the inner colon lining is thicker than normal.
Symptoms of Microscopic Colitis
Your symptoms can improve and worsen over time in a cycle of flares and remissions.
Symptoms of microscopic colitis may include:
- Fecal incontinence
- Increased urgency or frequency of bowel movements
- Abdominal cramping or bloating
- Weight loss
Risk Factors for Microscopic Colitis
Risk factors for microscopic colitis may include:
- Sex: Microscopic colitis is more common in female patients
- Family history: Researchers believe that genetics may play a role in microscopic colitis
- Comorbid conditions: Individuals with immune disorders such as celiac disease or rheumatoid arthritis are at higher risk for developing microscopic colitis
- Health history: Certain medications may increase your chances of developing microscopic colitis, including statins, hormonal therapies, beta blockers, proton pump inhibitors (PPIs), selective serotonin reuptake inhibitors (SSRIs), or non-steroidal anti-inflammatory drugs (NSAIDs)
- Lifestyle: Smoking is linked to an earlier age of condition onset
Diagnosing Microscopic Colitis
Microscopic colitis is diagnosed with a colonoscopy where a biopsy must be performed. During the colonoscopy, your physician will also collect a tissue sample (called a biopsy). The pathologist will examine the tissue under a microscope for signs of the condition.
Treating Microscopic Colitis
Medications that target your immune response can be used to achieve symptom remission. Lifestyle adjustments such as dietary changes and smoking cessation also play an important role in condition management. Surgery is rarely recommended for microscopic colitis but may be required if you do not respond to medication. Your physician will work with you to determine the most appropriate course of treatment.
Care Team Approach
Patients are cared for by a dedicated multidisciplinary care team, meaning you will benefit from the expertise of multiple specialists across a variety of disciplines. Our board-certified and fellowship-trained gastroenterologists have extensive experience with microscopic colitis and work alongside a team of digestive health experts, including colorectal surgeons, gastrointestinal-specialized dietitians, clinical social workers, physician assistants, nurses, advanced practice providers, and more, providing unparalleled care for patients every step of the way.
We collaborate with our colleagues at the Dell Medical School and The University of Texas at Austin to utilize the latest research, diagnostic, and treatment techniques, allowing us to identify new therapies to improve treatment outcomes. We are committed to communicating and coordinating your care with referring physicians and other partners in the community to ensure that we are providing you with comprehensive, whole-person care.