This document discusses the management of Crohn's disease in adults. It covers the clinical manifestations, natural history, prognostic factors, diagnosis, investigations including endoscopy and imaging, and medications used to treat mild to severe Crohn's disease. Treatment depends on the severity and location of inflammation, and may include mesalamine, corticosteroids, immunomodulators, anti-TNF agents, antibiotics, drainage of abscesses, and surgery. The goal of treatment is induction and maintenance of remission, and objective evaluation through endoscopy or imaging is important for monitoring disease activity over time.

1. MANAGEMENT OF CROHN’S
DISEASE IN ADULTS
Ahmed Elmoughazy, Hepato-gastroenterology unit, Medical research institute,
Alexandria University

2. BACKGROUND
 Crohn’s disease (CD) is an idiopathic inflammatory
bowel disease characterized by transmural non
caseating granulomatous inflammation.
 Crohn’s disease has an estimated prevalence 140–
200 per 100,000.
 The peak incidence is between ages 15 and 25
years, with a smaller second peak between the
fifth and seventh decades.
 The standardized mortality ratio is 1.4 for CD.

3. CLINICAL MANIFESTATION
 Symptoms of CD depend on the anatomical
location of the disease.
 The most common symptom of Crohn’s disease is
chronic diarrhea.
 With ileocecal disease: abdominal pain, diarrhea,
and fever are typical.
 With colonic disease: bloody bowel movements
with diarrhea, weight loss and low-grade fever.
 With gastroduodenal CD: epigastric pain and early
satiety
 With perianal CD: perirectal abscesses, painful
and edematous external hemorrhoids, and anal
and perianal fistulas.

4. EXTRA INTESTINAL MANIFESTATION OF CD

6. NATURAL HISTORY OF CD
 The location of Crohn’s disease tends to be stable, but can occasionally extend.
 Most patients with Crohn’s disease will present with non-penetrating, non-
stricturing disease behavior, 50% of them will develop an intestinal stricture,
abscess, or fistula within 20 years of diagnosis.
 Only 20–30% of patients with Crohn’s disease will have a non-progressive or
course.

7. PROGNOSTIC FACTORS
 Features that are associated with a high risk for progressive
disease burden include:
1. Young age at diagnosis.
2. Initial extensive bowel involvement.
3. Ileal/ ileocolonic involvement, perianal/severe rectal disease,
and patients presenting with a penetrating or stenosis disease
phenotype .

8. DIAGNOSIS
 There are no truly pathognomonic features of CD. Clinical, Endoscopic,
radiographic, and histologic criteria with evidence of chronic intestinal
inflammation are the four pillars to reach diagnosis.
 Initial laboratory investigation should include evaluation for inflammation,
anemia, dehydration, and malnutrition.
 Routine use of serologic markers of IBD to establish the diagnosis of Crohn’s
disease is not indicated.
 Fecal calprotectin is a helpful test that should be considered to help differentiate
the presence of IBD from irritable bowel syndrome (IBS).

9. INVESTIGATION : ENDOSCOPY
 Ileocolonoscopy with biopsies should be performed in the assessment of patients
with suspected Crohn’s disease.
 Distribution and severity should be documented at the time of diagnosis.
 Biopsies of uninvolved mucosa are recommended to identify extent of histologic
disease.
 In patients at particularly high risk for colorectal neoplasia (e.g., personal history
of dysplasia, primary sclerosing cholangitis), chromoendoscopy should be used
during colonoscopy.

10. INVESTIGATION: IMAGING
 Small bowel imaging should be performed as part of the initial diagnostic workup
for patients with suspected Crohn’s disease.
 Computed tomography enterography (CTE) is sensitive for the detection of small
bowel disease in patients with Crohn’s disease and is comparable to magnetic
resonance enterography (MRE) which is preferred in patients < 35 years old.
 MRI of the pelvis and/or endoscopic ultrasound may be used to characterize
perianal Crohn’s disease and perirectal abscesses.

11. MEDICATIONS (MILDTO MODERATE CD)
 Sulfasalazine is effective for treating symptoms of colonic Crohn’s disease.
 Oral mesalamine should not be used to treat patients with active Crohn’s disease.
 Controlled ileal release budesonide ( 9 mg once daily) should be used for induction
of remission in mild-to-moderate ileocecal Crohn’s disease.
 Ciprofloxacin OR Metronidazole have no role in treatment of this group of
patients.

12. MEDICATIONS (MODERATETO SEVERE CD)
 Oral corticosteroids are effective and can be used for short-term use in alleviating
signs and symptoms.
 Azathioprine (at doses of 1.5–2.5 mg/kg/day) can’t be used to induce remission,
but can be used for maintenance.
 Methotrexate (up to 25 mg once weekly IM or SC) can be used in induction and
maintenance specially in Corticosteroid dependent patients.
 Cyclosporine, mycophenolate mofetil, and tacrolimus should not be used for
Crohn’s disease.

13. MEDICATIONS (MODERATETO SEVERE CD)
• Anti-TNF agents (infliximab,
adalimumab, certolizumab
pegol) should be used in cases
resistant to corticosteroids or
refractory to Azathiopurine or
Methotrexate.
• Combination therapy of
infliximab with
immunomodulators
(thiopurines) is more effective
than treatment with either
immunomodulators alone or
infliximab alone in patients who
are naive to those agents.

14. MEDICATIONS (FULMINANT/FISTULIZING
CD)
 Intravenous corticosteroids should be used OR Anti-TNF agents can be considered
to treat severely active Crohn’s disease.
 Infliximab + Antibiotics is effective and should be considered in treating perianal
fistulas in Crohn’s disease.
 Drainage of abscesses (surgically or percutaneously) should be undertaken before
treatment of fistulizing Crohn’s disease with anti-TNF agents.
 An intra-abdominal abscess should be treated with antibiotics and a drainage
procedure, either radiographically or surgically.

15. BIOSIMILARS
 Biosimilar infliximab and biosimilar
adalimumab are effective treatments
for patients with moderate-to-severe
Crohn’s disease and can be used for
denovo induction and maintenance
therapy.

16. FOLLOW UP
 Symptoms of Crohn’s disease do not correlate well with the presence of active
inflammation, and therefore should not be the sole guide for therapy. Objective
evaluation by endoscopic or cross-sectional imaging should be undertaken
periodically to avoid errors of under- or over treatment.
 Mucosal healing as determined by endoscopy is a goal of therapy.
 Fecal calprotectin may have an adjunctive role in monitoring disease activity.

17. SIMPLE ENDOSCOPIC SCORE FOR CROHN’S
DISEASE

18. TAKE HOME MESSAGE
 Oral mesalamine has a limited role in CD.
 Biological treatment seems to get the upper hand in management of CD, and the
availability of cheaper biosimilars may increase its applicability.
 Fecal calprotectin is a helpful to differentiate IBD from IBS and as adjunctive in
follow up.
 Symptoms of Crohn’s disease does not correlate inflammation, Endoscopy is the
most accurate way of assessment in follow up.