Microscopic Colitis
Disease Details
Family Health Simplified
- Description
- Microscopic colitis is an inflammation of the colon that can cause chronic watery diarrhea, often diagnosed through biopsy as it appears normal during a colonoscopy.
- Type
- Microscopic colitis is classified into two main types: collagenous colitis and lymphocytic colitis. The genetic transmission of microscopic colitis is not well-defined, but it is generally not considered to be directly inherited in a Mendelian fashion. However, there may be a genetic predisposition that increases the risk of developing the condition, particularly in individuals with a family history of autoimmune diseases.
- Signs And Symptoms
- The main symptom is persistent non-bloody watery diarrhea, which may be profuse. People may also experience abdominal pain, fecal incontinence, and unintentional weight loss. Microscopic colitis is the diagnosis in around 10% of cases investigated for chronic non-bloody diarrhea.
- Prognosis
- The prognosis for lymphocytic colitis and collagenous colitis is good, and both conditions are considered to be benign. The majority of people afflicted with the conditions recover from their diarrhea, and their histological abnormalities resolve, although relapses commonly occur if maintenance treatment is not continued.
- Onset
- Microscopic colitis typically has a gradual onset. The disease often presents with chronic, non-bloody, watery diarrhea. The exact cause is not well understood, but it is believed to involve autoimmune mechanisms, infections, medications, and other factors.
- Prevalence
- The prevalence of microscopic colitis varies, but it is generally estimated to affect about 15 to 20 per 100,000 people annually. However, recent data suggest that it might be more common than previously thought, especially in older adults. It tends to be underdiagnosed due to its nonspecific symptoms and the requirement for colonoscopic biopsy for diagnosis.
- Epidemiology
- Incidence and prevalence of microscopic colitis nears those of ulcerative colitis and Crohn's disease. Studies in North America found incidence rates of 7.1 per 100,000 person-years and 12.6 per 100,000 person-years for collagenous colitis for lymphocytic colitis, respectively. Prevalence has been estimated as 103 cases per 100,000 persons.People who develop microscopic colitis are characteristically, though not exclusively, middle-aged females. The average age of diagnosis is 65 but 25% of cases are diagnosed below the age of 45.
- Intractability
- Microscopic colitis is generally not considered intractable. It can often be managed effectively with medications, dietary changes, and other supportive treatments. However, some patients may experience relapses or chronic symptoms that require ongoing management.
- Disease Severity
- Disease_severity: Microscopic colitis is generally considered a chronic but typically mild condition. It can vary from mild to moderate in severity with periods of intense symptoms, including chronic watery diarrhea, abdominal pain, and fatigue, which can significantly affect a person's quality of life. While it is not life-threatening, it requires medical management to control symptoms.
- Healthcare Professionals
- Disease Ontology ID - DOID:0060182
- Pathophysiology
- Microscopic colitis is an inflammatory condition of the colon characterized by chronic, non-bloody, watery diarrhea. The pathophysiology involves an increase in intraepithelial lymphocytes and a thickened subepithelial collagen layer or increased inflammatory cells in the lamina propria, depending on the subtype (collagenous colitis or lymphocytic colitis). The exact cause is not well understood but may involve immune system dysregulation, genetics, medication use, and certain infections.
- Carrier Status
- Microscopic colitis, including both lymphocytic and collagenous colitis, is not a condition with a defined carrier status, as it is not an inherited genetic disorder passed from parents to their offspring. Its exact cause is unclear, but it is thought to result from a combination of genetic predisposition, immune system factors, and environmental triggers.
- Mechanism
-
Microscopic colitis refers to an inflammatory condition of the colon, typically presenting with chronic, non-bloody diarrhea. It is divided into two primary subtypes: collagenous colitis and lymphocytic colitis.
### Mechanism:
1. **Collagenous Colitis**: Characterized by a thickened subepithelial collagen layer in the colon. This thickening disrupts the normal absorption and secretion processes of the colon, leading to diarrhea.
2. **Lymphocytic Colitis**: Marked by an increased number of intraepithelial lymphocytes. This immune cell infiltration disrupts the normal mucosal function, also resulting in diarrhea.
### Molecular Mechanisms:
1. **Immune Response**: Dysregulation of the immune response, including T-lymphocyte activation, is pivotal. In lymphocytic colitis, there is a notable increase in intraepithelial T-lymphocytes.
2. **Cytokines and Chemokines**: Elevated levels of inflammatory cytokines (e.g., TNF-alpha, IL-1, IL-6) and chemokines are often involved, perpetuating the inflammatory process.
3. **Matrix Metalloproteinases (MMPs)**: In collagenous colitis, MMPs are believed to facilitate the deposition and remodeling of the collagen layer under the epithelium.
4. **Epithelial Barrier Dysfunction**: Both subtypes may exhibit a compromised epithelial barrier, leading to increased intestinal permeability and persistent inflammation.
Overall, microscopic colitis results from complex interactions between genetic predisposition, immune system dysregulation, and environmental factors such as medications (like NSAIDs) and infections. - Treatment
- Lymphocytic and collagenous colitis have both been shown in randomized, placebo-controlled trials to respond well to budesonide, a glucocorticoid. Budesonide formulated to be active in the distal colon and rectum is effective for both active disease and in the prevention of relapse. However, relapse occurs frequently after withdrawal of therapy.Studies of a number of other agents including antidiarrheals, bismuth subsalicylate (Pepto-Bismol), mesalazine/mesalamine (alone or in combination with cholestyramine), systemic corticosteroids, cholestyramine, immunomodulators, and probiotics have shown to be less effective than budesonide for treating both forms of microscopic colitis.Anti-TNF inhibitors. split ileostomy, diverting ileostomy, and subtotal colectomy are options for management of steroid-dependent or refractory microscopic colitis. Currently, the need to resort to surgery is limited considering the improvement of drug therapy options. However, surgery is still considered for patients with severe, unresponsive microscopic colitis.
- Compassionate Use Treatment
-
Microscopic colitis is an inflammatory condition of the colon that presents with chronic, watery diarrhea. Clinical management primarily focuses on treatments such as budesonide, loperamide, and bismuth subsalicylate. However, when standard treatments are insufficient, off-label and compassionate use treatments may be considered.
1. **Compassionate Use Treatments**: In cases where conventional therapies have failed, medications like biologics (e.g., infliximab) may be used under compassionate use protocols to manage severe cases, although their efficacy and safety are still under investigation.
2. **Off-Label Treatments**: Various medications have been used off-label with varying degrees of success, including:
- Methotrexate: an immunosuppressant that may be considered in steroid-refractory microscopic colitis.
- Vedolizumab: a gut-specific monoclonal antibody used for inflammatory bowel disease, sometimes considered for microscopic colitis.
- Azathioprine or 6-Mercaptopurine: immunosuppressive treatments that may help in severe cases where other therapies fail.
3. **Experimental Treatments**: These are typically part of clinical trials and can include newer biologics, small molecule inhibitors, or other innovative therapies aiming to modulate the immune response more precisely.
It's essential for these treatments to be monitored by healthcare professionals due to potential side effects and the lack of extensive suitability data for microscopic colitis. - Lifestyle Recommendations
-
For microscopic colitis, lifestyle recommendations include:
1. **Dietary Adjustments**:
- Eat a balanced diet rich in fruits, vegetables, and whole grains.
- Avoid foods and beverages that can irritate the bowel, such as caffeine, alcohol, fatty foods, and artificial sweeteners.
- Consider a low-fat, low-fiber diet if symptoms are severe.
- Monitor and potentially eliminate lactose if dairy products worsen symptoms.
2. **Hydration**:
- Drink plenty of fluids to prevent dehydration, especially when experiencing diarrhea.
3. **Smoking Cessation**:
- Quit smoking, as smoking has been linked to worsening symptoms.
4. **Stress Management**:
- Engage in activities to reduce stress, such as exercise, yoga, meditation, and deep-breathing exercises.
5. **Regular Follow-ups**:
- Regularly consult with a healthcare provider to monitor and manage symptoms.
6. **Medication Adherence**:
- Follow prescribed treatments and medications as directed by a healthcare professional.
Implementing these lifestyle changes can help manage and possibly reduce the symptoms of microscopic colitis. - Medication
-
Microscopic colitis is an inflammatory bowel condition that encompasses two primary types: collagenous colitis and lymphocytic colitis. Medication options commonly include:
1. **Anti-inflammatory drugs**: Such as budesonide, a corticosteroid that can reduce inflammation.
2. **Immunosuppressive agents**: Drugs like azathioprine or methotrexate may be used in severe cases to suppress the immune response.
3. **Anti-diarrheal medications**: Loperamide or diphenoxylate/atropine to manage symptoms.
4. **Bile acid binders**: Such as cholestyramine for those who have bile acid-induced diarrhea.
5. **Probiotics**: Sometimes recommended to help maintain gut flora balance.
Treatment begins with the least invasive options and progresses based on symptom severity and response to initial therapies. - Repurposable Drugs
-
Microscopic colitis can potentially be managed with repurposable drugs such as:
1. **Budesonide:** Originally used for asthma and Crohn's disease, it has proven effective in treating microscopic colitis due to its anti-inflammatory properties.
2. **Mesalamine:** Typically used for ulcerative colitis, it can reduce inflammation in the colon.
3. **Methotrexate:** Often used for rheumatoid arthritis and certain cancers, it can be considered for severe cases resistant to other treatments.
4. **Rifaximin:** An antibiotic used for traveler's diarrhea and irritable bowel syndrome, it may help in reducing symptoms by altering gut flora.
Note: Always consult a healthcare professional before starting or changing treatment. - Metabolites
- Microscopic colitis is characterized primarily by chronic, non-bloody, watery diarrhea. The diagnosis is confirmed through histological examination of colonic biopsies. Metabolites are not typically used for diagnosis or management of this condition; instead, histological features such as an increased number of intraepithelial lymphocytes or other cellular changes in the colonic lining are pivotal. Specific metabolites associated with microscopic colitis have not been well-defined in the medical literature.
- Nutraceuticals
- Nutraceuticals have shown potential in managing microscopic colitis, though research is still ongoing. Some studies suggest that probiotics, omega-3 fatty acids, and curcumin may have beneficial effects in reducing inflammation and alleviating symptoms. However, it's important for patients to consult healthcare providers before starting any nutraceutical regimen to ensure safety and efficacy tailored to their specific condition.
- Peptides
- Microscopic colitis does not currently have a direct treatment involving peptides or nanotechnology. Management typically includes medications like anti-diarrheal agents, anti-inflammatory drugs (such as budesonide), and dietary modifications.