1. Crohn´s disease
Domina Petric, MD

2. Introduction
Crohn´s disease is a chronic inflammatory gastrointestinal disease characterised by transmural granulomatous inflammation affecting any part of the gut from mouth to anus.
There is unaffected bowel between areas of active disease: SKIP LESIONS.

3. Cause Cause is unknown. Environmental agents are implicated.
Genetics: mutations of the NOD2/CARD15.
Colon involvement goes with increased CARD15 gene expression in macrophages and intestinal epithelial cells.
Dysregulated immune responses might be primary or secondary (infecting gut commensals like Mycobacterium avium para-TB).
E. coli adhesins, p273, may play a role in developing Morbus Crohn.

4. Epidemiology Prevalence is 0,5-1/1000. More common in women.
Incidence is 5-10/100000/year.
Presentation is mostly at age of 20 to 40 years.
Smoking increases risk 3-4 times.
NSAID may exacerbate disease.

5. Symptoms diarrhoea and urgency abdominal pain
weight loss, failure to thrive
fever
malaise
anorexia

6. Diarrhoea is usually very smelly.
Symptoms
Patients can feel fine one minute, and deathly ill the next minute.
Diarrhoea is usually very smelly.

7. Signs in the GI tract
aphthous ulcerations
abdominal tenderness or mass
perianal abscess, fistulae
skin tags
anal strictures

8. Extraintestinal signs
clubbing
skin, joint and eye problems

9. Source: Meddiction.com
Skip lesions
Source: Meddiction.com

10. Complications small bowel obstruction
toxic dilatation (colonic diameter>6 cm)
abscess formation (abdominal, pelvic, ischiorectal)
fistulae (colovesical, colovaginal, perianal, enterocutaneous)

11. Complications rectal haemorrhage colon cancer fatty liver
primary sclerosing cholangitis
cholangiocarcinoma

12. Complications
renal stones
osteomalacia
malnutrition
amyloidosis

13. Blood tests Full blood count Erythrocyte sedimentation rate CRP
Urea, creatinine and electrolytes
INR, liver function tests
Ferritin, TIBC, B12, folate

14. Stool microbiology, faecal calprotectin Colonoscopy + rectal biopsy
Diagnostics
Stool microbiology, faecal calprotectin
Colonoscopy + rectal biopsy
Small bowel enema
Capsule endoscopy
Barium enema
MRI

15. Mild attack Symptomatic patient, but systemically well.
Prednisolone 30 mg/d per os for 1 week, then 20 mg/d for 4 weeks.
If symptoms resolve, prednisolone 5 mg every 2-4 weeks.
When parameters are normal, stop prednisolone.

16. Severe attacks Patient is systemically ill.
Admit in the hospital for iv. steroids.
Nil by mouth!
Iv. infusion 1 L 0,9% saline + 2 L dextrose-saline/24 hours + 20 mmol K+/L (less potassium in elderly).

17. Severe attacks Hydrocortisone 100 mg/6 h iv.
Hydrocortisone 100 mg in 100 mL 0,9% saline/12 hours per rectum is effective treatment for rectal disease.
Metronidazole 400 mg/8 hours per os or 500 mg/8 hours iv. can be useful in perianal disease or superadded infection.

18. Severe attacks
Daily physical examination with full blood count, erythrocyte sedimentation rate, CRP, urea, creatinine and eletrolytes.
Plain abdominal X ray.
Consider need for blood transfusion and parenteral nutrition.

19. Severe attacks
If the patient is improving after 5 days, transfer to oral prednisolone 40 mg/day.
If the patient is not improving, INFLIXIMAB or ADALIMUMAB.
In the case of severe abdominal pain, consider abdominal sepsis complicating Crohn´s disease.

20. Medications for Morbus Crohn

21. Azathioprine Dose is 2-2,5 mg/kg/day per os.
It can be used as a steroid-sparing agent.
It takes 6-10 weeks for clinical improvement.

22. Sulfasalazine
Although unproven efficacy, sulfasalazine is useful in Crohn´s disease, especially high-dose postoperatively in patients with ileal resection.

23. TNFα inhibitors
Infliximab and adalimumab can decrease disease activity because TNFα plays important role in pathogenesis of Crohn´s disease.
They counter neutrophil accumulation and granuloma formation, activate complement and cause cytotoxicity to CD4+ T-cells.

24. Methotrexate
Methotrexate 25 mg im. weekly for remission induction is enabling complete withdrawal from steroids in patients with refractory Crohn´s disease.

25. Nutrition
Enteral nutrition is preferred (polymeric diet) over the total parenteral nutrition in exacerbations.
Low residue diets help control Crohn´s activity.

26. Literature
Oxford Handbook of Clinical Medicine. Longmore M. Wilkinson I. B. Baldwin A. Elizabeth W. Ninth edition.
Meddiction.com
Wikipedia.org