Definition of Crohn's disease
Crohn’s disease is another inflammatory bowel disease. Crohn’s disease involves the terminal ileon only in approximately 30% of cases, in approximately 50%,it is an ileon-colonic disease, and sometimes it affects only the colon. In fact, any segmentbof digestive tube might be affected (including the esophagus, stomach, duoden or appendix but much more rarely).
Etiopathogenesis of Crohn's disease
Bacteria (mycobacterium, pseudomonas), viruses, food allergy, environment factors as well as smoking and industrial toxic agents were implied; genetic factors (familial or ethnic) participate in the apparition and persistence of the disease. Therefore, the genetic predisposition for Crohn’s disease is big, with an increased risk in Jews. The role of immune factors (umoral and cellular) and stress in the onset of Crohn’s disease episodes is also known.
Clinical features of Crohn's disease
Clinical picture may be almost absent or absent, but sometimes it suggests the disease.
Typical clinical signs are:
1. digestive
- diarrhea(without blood)
- abdominal pain
- malabsorbtion
- perianal lesions(fistulas)
2. extradigestive
- fever or low-grade fever
- fatigue
- weight loss
- arthritis
- erythema nodosum
- uveitis
The clinical context in which we might think of this disease is chronic diarrhea (even if only 2-4 stools/day), low-grade fever, fatigue, perianal fistulas and fissuring.
Diagnosis of Crohn's disease
The diagnosis is primarily based on the endoscopy with biopsy. Aphthout lesions will be discovered, together with deep, linear ulcerations, cobblestone relief of the mucosa, areas of inflammatory stenosis. These lesions may be located in the terminal ileon, colon, but also in the in the esophagus or duodenum. Thus, total colonoscopy with evalution of terminal ileon, but also gastroduodenoscopy is needed. The biopsy is compulsory, revealing the transmural inflammatory and the granulomatous aspect. The presence of profound ulcerations, fibrosis, and fissures is the rule.
X-ray examination is useful when the endoscopy is not accessible barium enema with ileal reflux or enteroclysis (barium administration by duodenal probe) may be used to demonstrate the lesions of terminal ileon or even barium examination, followed-up at 1, 2, 3 and 4 hours. The pathologic aspect:”cobblestone relief” in the terminal ileon, presence of some areas with stenosis (narrowing of the lumen) with enlargements above, and fistulas.
Abdominal ultrasound examination will reveal the thickening of intestinal wall, thus evaluating the extension of the affected area. The zones of stenosis and dilatation may be evaluated, as well as the presence of some possible complications, such as perforation, fistulas.
The biologic picture in the episode will reveal the inflammatory syndrome with an increasing of ESR, leukocytosis, fibrinogen, RCP. Anemia and hypoalbuminemia may also appear.
The staging of disease
It is done by a few parameters. It quantifies the number of stools, abdominal pain, general well being, complications, use of antidiarrheic drugs, abdominal mass, hematocrit and body weight.
CDAI <150= inactive disease
CDAI 150-219= mild form
CDAI 220-450=moderate form
CDAI >450= severe form
There is an easier classification of Crohn’s disease, elaborated in Vienna –The Vienna classification of Crohn’s disease:ALB (Age, Location, Behavior)
A (Age at diagnostic)
- A1 <40 years
- A2 >40 years
L(Location)
- L1 terminal ileum
- L2 colon
- L3 ileum and colon in the same time
- L4 superior digestive tract
B(Behavior)
- B1 nonstenosis, nonpenetrating form
- B2 stenotic form
- B3 penetrating form.
The differential diagnosis is made with:
- ulcerative colitis
- ischemic colitis, irradiation colitis
- colon neoplasm
- acute appendicitis
Evolution of Crohn's disease
It is characterized by recurrences. In general, more than 50% of cases relapse after an initial resection. Some studies have shown that the relapses frequency is reversely proportional with the time between diagnosis and first resection
Complications of Crohn’s disease
Complications are a rule in this disease. They are:
- stenosis
- fistulas (internal or external)
- perforation
- abcess appearance
- septic state
Treatment of Crohn’s disease
In the acute phase of the disease, it starts with:
Prednisone (or Hydrocortisone hemisuccinate, p.e.v. if needed) 60mg/day,tapering he dose with 10 mg/week, so after 6 weeks the dose will be approx. 15-10 mg/day.The treatment continues with 10 mg/day for 6 months if there is a clinical remission;if needed should be given another 6 months (every 2 days 5-10 mg).
- Mesalazine 1,5-2 g/day
- Imuran (Azathioprine) 2-3 mg/kg body/day (for at least 3 months)
- Metronidazole 500-1000mg/day
- Budesonide(Budenofalk or Entocort) –the attack dose is 9 mg/day, continuing then with 3 mg/day
The surgical treatment addresses especially to the complications, such as segmental stenosis or perforations or nonresponsive forms to the drug therapy. The interventions may be segmental resections with anastomosis, or, more rarely, the colectomy with ileorectal anastomosis, or proctocolectomy with ileostomy(in the severe and invalidating relapses).
