Inflammatory Bowel Disease

Introduction to Inflammatory Bowel Disease

• Inflammatory bowel disease (IBD) includes conditions such as ulcerative colitis and Crohn's disease, which are distinct gastrointestinal disorders with different pathophysiology, diagnostic criteria, and treatment approaches, though they may occasionally coexist in the same patient 1, 2
• The European Crohn's and Colitis Organisation and American College of Gastroenterology guidelines recommend assessing recent travel history, infectious exposures, medication history, smoking status, and prior appendectomy in patients with ulcerative colitis, as these factors may influence risk 3

Environmental Toxins and Inflammatory Bowel Disease

• Exposure to PFAS (per- and polyfluoroalkyl substances) has been associated with limited suggestive evidence of an association with ulcerative colitis, according to a recent report 3
• The American College of Gastroenterology guidelines emphasize the importance of considering environmental factors, including toxins like PFAS, in the development of ulcerative colitis 4, 5

Diagnosis of Inflammatory Bowel Disease

• Diagnostic tests should include:
• Clinical presentation should be assessed, including onset of symptoms, rectal bleeding, stool consistency and frequency, urgency, tenesmus, abdominal pain, incontinence, and nocturnal diarrhea, as noted by the European Crohn's and Colitis Organisation 6
• Patient history should include recent travel, possible infectious exposures, medication history, smoking status, and family history of inflammatory bowel disease or colorectal cancer, as recommended by the American College of Gastroenterology 6
• The European Society for Pediatric Gastroenterology, Hepatology and Nutrition recommends serologic testing, including tissue transglutaminase antibodies (TG2Ab) and endomysial antibodies, for the diagnosis of celiac disease 1
• The American College of Gastroenterology suggests that endoscopic findings, such as aphthoid ulcers, cobblestoning, and skip lesions, and histology, including focal chronic inflammation and granulomas, are important for the diagnosis of Crohn's disease 7

Treatment of Inflammatory Bowel Disease

• The American College of Gastroenterology recommends managing ulcerative colitis according to standard treatment guidelines, including the use of 5-ASA compounds for mild-moderate disease and immunomodulators and biologics for moderate-severe disease 4, 5
• The American College of Gastroenterology recommends a lifelong strict gluten-free diet as the mainstay of treatment for celiac disease, with monitoring using serological testing and nutritional supplementation as needed 8
• The Crohn's and Colitis Foundation notes that immunosuppressive medications, such as corticosteroids, thiopurines, and biologics, and surgery for complications, are important treatment options for Crohn's disease 7
• Budesonide is considered first-line treatment for microscopic colitis, with a recommended dose of 9 mg daily for 8 weeks 9
• Discontinuation of the suspected triggering medication is recommended if clinically feasible when microscopic colitis is diagnosed in a patient taking potential triggering medications 9

Complications and Risk Factors of Inflammatory Bowel Disease

• Patients with celiac disease are at increased risk of refractory celiac disease, small bowel lymphoma, osteoporosis, and nutritional deficiencies 1
• Patients with Crohn's disease are at increased risk of intestinal strictures and obstruction, fistulas and abscesses, colorectal cancer, and extraintestinal manifestations affecting joints, skin, eyes, and liver 1
• The World Gastroenterology Organisation recommends considering testing for celiac disease in Crohn's patients with persistent iron deficiency anemia, symptoms that persist despite adequate Crohn's disease control, family history of celiac disease, or associated autoimmune conditions 1
• Patients with long-standing IBD have a higher risk of colorectal cancer, with a cumulative risk of 1%, 2%, and 5% after 10, 20, and more than 20 years of disease duration, respectively 10
• Primary sclerosing cholangitis (PSC) concomitantly increases the risk of colorectal cancer significantly, as reported by 11, 10
• Family history increases the risk of IBD, with an incidence rate ratio of 4.08 for first-degree relatives, and 1.85 for second-degree relatives 6
• Genetic mutations, including CARD15/NOD2, OCTN1, OCTN2, and DLG5 genes, are associated with an increased risk of IBD 1
• Infections may trigger the onset of IBD or cause disease flares 2
• Smoking has a protective effect against Colitis Ulcerosa, but increases the risk of developing Crohn's Disease and worsens its clinical course 6
• Appendectomy for confirmed appendicitis before adulthood reduces the risk of Colitis Ulcerosa 6
• Risk factors for colitis include immunosuppressive treatments, malnutrition, obese BMI, comorbidities, active disease, and older age, as noted by the American Gastroenterological Association 12
• Age has a bimodal distribution with peaks in 10-40 years and >60 years 1
• Ethnicity has a higher incidence in certain groups, such as Ashkenazi Jews 1
• Regular surveillance for colorectal cancer is recommended in patients with longstanding ulcerative colitis, according to guidelines from the American College of Gastroenterology and the European Crohn's and Colitis Organisation 13, 6