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Ulcerative Colitis

Ulcerative Colitis (UC) is a chronic inflammatory bowel disease (IBD) characterized by long-lasting inflammation and ulcers in the innermost lining of the large intestine (colon) and rectum. It is an autoimmune condition in which the immune system mistakenly attacks the cells of the colon, resulting in inflammation, bleeding, and ulcer formation. UC typically follows a relapsing-remitting course, with periods of flare-ups and remission.

The condition significantly affects quality of life and can lead to severe complications if not properly managed. Though there is no cure, medical advancements and emerging therapies such as stem cell therapy and hyperbaric oxygen therapy (HBOT) offer promising avenues for improved outcomes.

Causes and Risk Factors

The exact cause of UC is unknown, but it is thought to be multifactorial, involving genetic, immune, and environmental factors.

  • Genetic predisposition: A family history of IBD increases the risk.
  • Immune system dysfunction: An abnormal immune response attacks the cells of the digestive tract.
  • Environmental triggers: Infections, diet, and changes in gut microbiota may influence disease onset or flares.
  • Age and ethnicity: UC can occur at any age but is most commonly diagnosed between ages 15 and 30. It is more prevalent in people of European descent.

Pathophysiology

In UC, the immune system becomes dysregulated, causing chronic inflammation confined to the mucosal layer of the colon and rectum. This inflammation leads to ulceration, bleeding, and impaired absorption of water and nutrients.

The disease typically begins in the rectum (proctitis) and may extend proximally to involve the entire colon (pancolitis). Unlike Crohn’s disease, UC is continuous and does not affect other parts of the gastrointestinal tract.

Symptoms

Symptoms of UC can vary depending on the severity and extent of the disease. Common symptoms include:

  • Abdominal pain and cramping
  • Diarrhea, often with blood or pus
  • Urgency to defecate and inability to hold bowel movements
  • Rectal bleeding
  • Weight loss and fatigue
  • Fever (in severe cases)
  • Anemia due to blood loss

Extraintestinal manifestations may also occur, affecting the skin, joints, eyes, and liver.

Classification

UC is classified based on the location and severity of inflammation:

  • Proctitis: Involves only the rectum
  • Left-sided colitis: Involves the rectum and left side of the colon
  • Pancolitis: Involves the entire colon

Disease severity is categorized as mild, moderate, or severe based on symptoms, frequency of bowel movements, and systemic signs.

Diagnosis

Diagnosis involves a combination of clinical evaluation, laboratory tests, and imaging:

  • Medical history and physical exam
  • Blood tests: Elevated inflammatory markers (ESR, CRP), anemia
  • Stool tests: To rule out infections and detect inflammatory markers (calprotectin)
  • Colonoscopy with biopsy: Gold standard for diagnosing UC, reveals continuous inflammation and ulceration
  • Imaging: CT or MRI enterography for assessing complications

Conventional Treatment

Treatment aims to reduce inflammation, induce remission, and prevent flare-ups. The choice of therapy depends on disease severity and location.

  • Aminosalicylates (5-ASAs): Mesalamine, sulfasalazine for mild-to-moderate disease
  • Corticosteroids: Prednisone, budesonide for inducing remission in moderate-to-severe flares
  • Immunomodulators: Azathioprine, 6-mercaptopurine for maintenance therapy

Biologic therapies:

  • Anti-TNF agents (infliximab, adalimumab)
  • Anti-integrin agents (vedolizumab)
  • IL-12/23 inhibitors (ustekinumab)

JAK inhibitors: Tofacitinib for moderate-to-severe UC

Supportive care includes antidiarrheals, pain management, and nutritional support.

Surgical Intervention

Surgery may be necessary in cases of:

  • Severe disease unresponsive to medical therapy
  • Life-threatening complications (e.g., toxic megacolon, perforation)
  • High-grade dysplasia or colorectal cancer

Total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the most common surgical procedure for UC.

Stem Cell Therapy in Ulcerative Colitis

Stem cell therapy is being explored for UC, particularly in refractory cases.

Types of stem cells:

  • Mesenchymal stem cells (MSCs): Most commonly used due to immunomodulatory properties
  • Hematopoietic stem cells (HSCs): Used in immune reset approaches

Mechanism of action:

  • Immunosuppression and regulation of inflammatory pathways
  • Promotion of tissue repair and regeneration
  • Restoration of intestinal epithelial barrier function

Clinical evidence:

  • By using MSCs (via intravenous or local injection) have shown safety and moderate efficacy
  • Some patients experience mucosal healing and reduced steroid dependence

Hyperbaric Oxygen Therapy (HBOT) for Ulcerative Colitis

HBOT is an adjunctive therapy that involves breathing pure oxygen in a pressurized chamber, enhancing oxygen delivery to tissues.
Mechanism:

  • Reduces intestinal inflammation and oxidative stress
  • Enhances angiogenesis and mucosal repair
  • Inhibits inflammatory cytokines
  • Modulates immune response

Clinical applications:

  • Useful in treating acute severe UC and refractory cases
  • Studies have shown improvement in symptoms, endoscopic scores, and quality of life

Protocol:

  • Typically involves multiple 60–90 minute sessions over several weeks

Lifestyle and Dietary Management

  • Diet: No one-size-fits-all diet, but a low-residue or low-FODMAP diet may help during flares
  • Hydration: Essential to prevent dehydration due to diarrhea
  • Stress management: Stress may exacerbate symptoms; mindfulness and counseling may help
  • Exercise: Regular activity supports overall health and reduces inflammation

Monitoring and Follow-Up

  • Regular colonoscopies to monitor disease progression and screen for colorectal cancer
  • Frequent blood and stool tests to assess inflammation and medication side effects

Prognosis

UC is a chronic disease with a variable course. With appropriate treatment, many patients can achieve long-term remission. However, some may experience frequent flares or require surgery. The risk of colorectal cancer increases with long-standing, extensive disease, necessitating vigilant screening.

Conclusion

Ulcerative Colitis is a complex autoimmune condition that requires individualized, long-term management. While conventional therapies remain the cornerstone of treatment, regenerative options such as stem cell therapy and HBOT offer promising potential, especially for patients with refractory disease. A comprehensive approach involving medication, diet, lifestyle modifications, and regular monitoring can significantly improve outcomes and enhance the quality of life for patients living with UC.