Inflammatory Bowel Disease Diagnosis and Management

Introduction to Ileitis

Erosive chronic active ileitis is most commonly associated with Crohn's disease and "backwash ileitis" in ulcerative colitis, which is seen in up to 20% of patients with extensive colitis, according to the European Crohn’s and Colitis Organisation 1, 2
Crohn's Disease is the most common cause of terminal ileitis, characterized by transmural inflammation that can occur throughout the GI tract, with the terminal ileum being a common localization 2

A detailed symptom assessment, including abdominal pain, diarrhea, and rectal bleeding, as well as medication history, family history of IBD, and extra-intestinal manifestations, is essential for diagnosis, as recommended by the American Gastroenterological Association 3
Stool studies, including cultures for infectious causes, fecal calprotectin, C. difficile testing, and parasites, are necessary for diagnosis, as suggested by the Infectious Diseases Society of America 3
Complete ileocolonoscopy with biopsies from multiple sites, including the terminal ileum, colon, and rectum, is crucial for diagnosis, according to the American Society for Gastrointestinal Endoscopy 4
Consider upper endoscopy with biopsies, especially if Crohn's disease is suspected, as recommended by the European Society of Gastrointestinal Endoscopy 4
CT or MR enterography is particularly valuable for detecting strictures, fistulas, or abscesses in terminal ileitis 5
Ileocolonoscopy with biopsies can assess for characteristic features of Crohn's disease, infectious causes, and NSAID-induced terminal ileitis, including discontinuous inflammation, cobblestoning, deep ulcers, and diaphragm-like strictures 2

For mild ileocolonic disease, high-dose mesalazine (4 g/daily) is recommended, according to the American College of Gastroenterology 6
For moderate to severe disease, oral corticosteroids (prednisolone 40 mg daily) are suggested, as recommended by the National Institute for Health and Care Excellence 6
For severe disease, intravenous steroids with concomitant metronidazole are recommended, according to the American College of Gastroenterology 6
Consider immunomodulators or biologics for maintenance therapy, as suggested by the Crohn's & Colitis Foundation 6
The European Crohn’s and Colitis Organisation recommends a step-up approach for medical therapy based on disease severity, including corticosteroids, immunomodulators, and biologics 2
Appropriate antimicrobial therapy is recommended for infectious causes of terminal ileitis 7
Discontinuation of the offending drug is recommended for NSAID-induced terminal ileitis 7
Treatment of underlying conditions such as vasculitis and spondyloarthropathies is necessary for terminal ileitis caused by these conditions 7

Repeat endoscopic assessment to monitor response to therapy, as recommended by the American Society for Gastrointestinal Endoscopy 4
Fecal calprotectin monitoring to assess disease activity, according to the European Crohn’s and Colitis Organisation 1
Regular clinical follow-up to assess for symptom improvement, as suggested by the American Gastroenterological Association 3
Postoperative prophylaxis with thiopurines or anti-TNF agents is recommended for patients who undergo surgical resection for Crohn's terminal ileitis, with high-dose mesalazine as an option for patients with isolated ileal resection 7
Terminal ileitis found incidentally during surgery for suspected appendicitis should not automatically lead to resection, as this carries risk of complications 7