Management of Ileitis
For active ileal or ileocolonic Crohn's disease, treatment should be stratified by severity: mild disease can be treated with high-dose mesalazine (4 g/daily), moderate to severe disease requires oral corticosteroids (prednisolone 40 mg daily), and isolated ileo-caecal disease may be treated with budesonide 9 mg daily. 1
Initial Assessment and Diagnosis
Before initiating treatment, you must first determine whether the ileitis represents Crohn's disease, intestinal tuberculosis, or a nonspecific etiology that may resolve with symptomatic management alone. The distinction is critical because it fundamentally changes your therapeutic approach and long-term management strategy.
Key diagnostic features that suggest specific etiology (CD or ITB) requiring treatment:
- Deep ulcers on colonoscopy (nearly 100% predictive of CD/ITB) 2
- Presence of fever, diarrhea, GI bleeding, or weight loss 2
- Radiologic signs of complicated disease (strictures, fistulae, abscesses) 3
- Laboratory findings: elevated platelet count, low MCV, anemia 3
- Male gender, younger age (<30 years), chronic abdominal pain history 3
Important caveat: In asymptomatic patients with incidentally discovered terminal ileitis on screening colonoscopy, watchful waiting is reasonable as progression to overt Crohn's disease is rare (pooled prevalence 1.6%) 4, 5. However, symptomatic ileitis demands active evaluation and treatment.
Treatment Algorithm for Active Crohn's Ileitis
Mild Disease (CDAI 180-250)
Start with high-dose mesalazine 4 g daily as first-line therapy 1. The microgranular formulation (Eudragit S-coated) may be more effective than standard tablets for ileal disease, with remission rates of 79% versus 60% respectively 6. This approach avoids corticosteroid side effects while maintaining comparable efficacy.
Moderate to Severe Disease (CDAI >250)
Initiate oral prednisolone 40 mg daily for patients who fail mesalazine or present with moderate-to-severe symptoms 1. Taper gradually over 8 weeks—more rapid reduction increases early relapse risk 1.
Critical consideration: The 2025 BSG guidelines now advocate for early advanced therapy (biologics/small molecules) in moderate-to-severe disease rather than relying solely on corticosteroids 7. Whenever prescribing systemic corticosteroids, simultaneously consider whether initiation of advanced therapy is warranted to avoid repeated steroid courses.
Isolated Ileo-Caecal Disease with Moderate Activity
Budesonide 9 mg daily is appropriate as it provides targeted ileal delivery with fewer systemic side effects than prednisolone, though it is marginally less effective 1. Treatment duration should not exceed 12 weeks 7.
Severe Disease
Administer IV corticosteroids (hydrocortisone 400 mg/day or methylprednisolone 60 mg/day) with concomitant IV metronidazole, as distinguishing active disease from septic complications can be difficult 1. This requires inpatient management with multidisciplinary involvement.
Adjunctive and Alternative Therapies
Azathioprine (1.5-2.5 mg/kg/day) or mercaptopurine (0.75-1.5 mg/kg/day) should be added as steroid-sparing agents in active disease, though their slow onset precludes use as sole therapy 1. These become essential for maintenance if patients relapse more than once yearly during steroid withdrawal 1.
Nutritional therapy (elemental or polymeric diets) is less effective than corticosteroids but appropriate for patients with contraindications to steroids or those preferring to avoid them 1. Consider as adjunctive therapy in all cases 1.
Infliximab 5 mg/kg is effective for induction but should be avoided in patients with obstructive symptoms 1. Reserve for refractory disease or as part of early advanced therapy strategy in moderate-to-severe cases 7.
Maintenance of Remission
All smokers must be counseled to stop—this is the single most important factor in maintaining remission 1.
Mesalazine has limited benefit for maintenance and is ineffective at doses <2 g/day or in patients requiring steroids for induction 1.
Azathioprine/mercaptopurine are effective but reserved as second-line maintenance due to toxicity concerns 1. Use when patients relapse more than once yearly during steroid withdrawal.
Corticosteroids (including budesonide) are not effective for maintenance and should not be continued long-term 1, 7.
Common Pitfalls to Avoid
Do not assume all terminal ileitis is Crohn's disease. Rule out intestinal tuberculosis, helminth infections 8, and consider that nonspecific ileitis may resolve without immunosuppression 2, 9.
Do not continue corticosteroids beyond 8-12 weeks. Prolonged use increases adverse events without maintenance benefit 1, 7.
Do not use mesalazine alone for moderate-to-severe disease. It is insufficient and delays effective treatment 1.
Do not ignore the need for surgical consultation. Surgery may be appropriate as primary therapy for limited ileal disease or after medical failure 1.
Do not overlook alternative diagnoses in patients with superficial ulcers, nonspecific histology, and absence of systemic symptoms—these have 92% negative predictive value for excluding CD/ITB 2.