Microscopic colitis (MC) is a type of inflammatory bowel disease (IBD) that causes inflammation within the colon. Unlike Crohn’s disease or ulcerative colitis, which are also forms of IBD, microscopic colitis is characterized by inflammation that is not visible to the naked eye during a colonoscopy. The condition’s name reflects this characteristic, as diagnosis requires examining a tissue sample under a microscope.
Understanding Microscopic Colitis
Microscopic colitis manifests in two primary forms: collagenous colitis and lymphocytic colitis. In collagenous colitis, the layer of collagen directly beneath the colon’s lining becomes thicker than usual. Lymphocytic colitis, in contrast, shows an increased number of white blood cells, specifically lymphocytes, within the colon lining, while the collagen layer remains normal or only slightly thickened.
Diagnosis requires a biopsy during a colonoscopy, with tissue samples examined under a microscope to reveal inflammatory changes not visible to the naked eye. Common symptoms associated with both types include chronic watery diarrhea, along with abdominal pain, cramping, and bloating.
Prognosis and Remission
Microscopic colitis is considered a chronic condition, meaning it can persist over a person’s lifetime, but its symptoms often fluctuate. Many individuals with microscopic colitis experience periods of remission, where symptoms significantly improve or resolve completely. Remission can occur spontaneously for some patients, leading to prolonged symptom-free periods. However, it is not typically cured, and even in remission, the underlying condition remains, making symptom recurrence possible.
The goal of treatment is to achieve clinical remission, which means experiencing few or no symptoms. While effective treatments can induce remission, relapse rates after discontinuing medication can be considerable, with studies reporting recurrence in over 50% of patients. Despite the potential for recurrence, the long-term outlook is generally favorable, with over 75% of individuals achieving long-term remission. Even when diarrhea resolves, some individuals may continue to experience other symptoms like abdominal pain, fatigue, or joint discomfort.
Managing Persistent Symptoms
When symptoms of microscopic colitis do not resolve on their own or return after a period of remission, various management strategies are available. Initial approaches often involve lifestyle and dietary adjustments, such as avoiding known triggers like certain medications including NSAIDs, proton pump inhibitors, and SSRIs. Dietary modifications like adopting a low-fat and low-fiber diet, or eliminating dairy, gluten, caffeine, sugar, and alcohol, can also help alleviate symptoms.
For pharmacological intervention, anti-diarrheal medications such as loperamide or diphenoxylate can be used to manage mild symptoms by slowing down bowel movements. Bismuth subsalicylate is another option that may help reduce diarrhea. For more persistent or severe symptoms, budesonide, a corticosteroid with targeted action in the gut, is a commonly recommended first-line treatment, typically administered for a set period to induce remission. If symptoms persist or recur after budesonide, other treatments like bile acid sequestrants, immunomodulators (e.g., thiopurines), or biologics (e.g., TNF inhibitors) may be considered for severe cases.
Living with Microscopic Colitis
This highlights the importance of ongoing management and monitoring to address potential flare-ups. A long-term perspective involves understanding that while the condition may not “go away” permanently, it is generally manageable, and individuals can maintain a good quality of life.
The prognosis for microscopic colitis is generally favorable, and it is distinct from other forms of inflammatory bowel disease, such as Crohn’s disease or ulcerative colitis. Notably, microscopic colitis does not increase an individual’s risk of developing colorectal cancer. In fact, some research suggests a potentially reduced risk of colorectal adenoma and cancer in individuals with microscopic colitis compared to the general population.
Despite the generally positive long-term outlook, microscopic colitis can impact an individual’s quality of life. Even during periods of remission, some patients may experience lingering symptoms like abdominal pain, fatigue, or joint discomfort. Working closely with a healthcare provider for personalized management and support is important to navigate the chronic nature of the condition and address any persistent symptoms.