What is Crohns disease?
- Chronic, transmural inflammatory disease of the GIT for which the cause is unknownQ.
- Can involve any part of the alimentary tract from the mouth to the anus but most commonly affects the small intestine and colonQ
Etiology of Crohns disease?
Infectious agents proposed as potential causes: Mycobacterium paratuberculosis and measles virusQ
Genetics for IBD?
- IBD-1 (chromosome 16q) - specific for Crohn’s diseaseQ
- IBD-2 (chromosome 12q) - common in Ulcerative colitisQ
Earliest gross pathologic lesion in Crohns disease?
Superficial aphthous ulcerQ
Pathology of crohns disease?
- • Skip areasQ
- • Extensive fat wrapping caused by the circumferential growth of the mesenteric fatQ around the bowel wall.
- • Thickened, firm, rubbery, and almost incompressible bowel wallQ.
- • Involved segments are adherent to adjacent intestinal loops or other viscera, with internal fistulasQ.
- • Mesentery of the involved segment is thickened, with enlarged lymph nodesQ.
- • (cobblestone appearanceQ
Histologic lesions of Crohn’s disease?
Noncaseating granulomas with Langerhans’ giant cellsQ.
Difference in clinical feature in ulcerative colitis ans Crohns disease?
- CD - In contrast to ulcerative colitis, patients with Crohn’s disease typically have fewer bowel movements, and the stools rarely contain mucus, pus, or bloodQ
- UC - Diarrhea with passage of mucusQ • More urgency than with Crohn’s disease, because of distal proctitisQ
MC site of fistula (enterocutaneous and enterovesical), perforation and carcinomaQ in Crohns disease?
Serology if IBD?
- Anti-Saccharomyces cerevisiae (ASCAQ) autoantibodies – Positive for Crohn’s disease
- p-ANCA - having 92% specificity for UCQ
- [@ ANCA Negative for crohNs disease]
Surgery in IBD?
Surgery is palliative in Crohn’s diseaseQ whereas curative in ulcerative colitisQ
Common Causes of Colovesical Fistula?
- Diverticulitis (50–60% More common in patients > 40 yearsQ
- CA colon (20–25% More common in patients > 50 yearsQ
- Crohn’s disease 10% Seen in 2nd to 3rd decade
Managemet of Fissures caused by Crohn’s disease?
- Are often multiple and located off the midline
- Usually respond to conservative measuresQ, such as sitz baths, stool softeners, and oral analgesics.
- Sphincterotomy and fissurectomy should be avoided in perianal Crohn’s diseaseQ
Management of fistulizing Crohns disease?
- InfliximabQ - closure rates between 25% and 67%.
- Abscesses need to be drained and fistula tracts require chronic drainage with non-cutting setonsQ.
- Once the perianal sepsis is controlled, infliximab treatment is initiated.
- After two to three infliximab infusions, the setons are removed to permit closure of the fistulasQ.
Etiology of Ulcerative colitis?
- C. difficile and Campylobacter jejuniQ
- Family history of IBD is a significant risk factorQ.
- Smoking and Appendectomy appears to confer a protective effectQ
- Both UC and Crohn’s disease are more common in women who use OCPsQ
Pathology of ulcerative colitis?
- Involves the mucosa and submucosa of the colon, with sparing of the muscularisQ.
- Typical gross appearance: Hyperemic mucosaQ
- Rectal involvement (proctitis) is the hallmark of the diseaseQ, and the diagnosis should be seriously questioned if the rectal mucosa is not affected.
- Pseudopolyps, or inflammatory polyps are seen in UC.
- Diagnostic characteristic of UC: Continuous uninterrupted inflammation of the colonic mucosa, beginning in the distal rectum and extending proximallyQ to a variable distance.
Most characteristic lesion of UC?
- Crypt abscessQ (collections of neutrophils fill and expand the lumina of individual crypts of Lieberkühn)
- Crypt abscesses are not specific for UCQ
Disease severity of UC can be graded by?
Modified Truelove and Witts ClassificationQ
What are extraintestinal manifestations of IBD?
- Pyoderma gangrenosum is more common in UCQ.
- EPASU is more common in Crohn’s diseaseQ.
- EPASU: Erythema nodosum, Peripheral arthritis, Ankylosing spondylitis, Stones (Cholilithiasis and oxalate stones), Ureteral obstructionQ
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Most frequent genitourinary complications of IBD?
Calculi, ureteral obstruction, and ileal bladder fistulasQ
Treatment of UC?
- • Older patients or those with fecal incontinence - total proctocolectomy with an end ileostomy.
- • Younger patients with no evidence of rectal dysplasia - restorative proctocolectomy and IPAA with a double-stapled anastomosis and diverting loop ileostomy.
- • Patients with confirmed rectal dysplasia - mucosectomy and a hand-sewn IPAA.
- • Patients with significant debility who are poor operative candidates - total abdominal colectomy with a very low Hartmann closure and an end ileostomy.
Management protocol of IBD?
- Mainstay of therapy for UC and CD - 5-ASA Derivatives
- Uncontrolled IBD or exacerbation - Glucocorticoids
- • Effective for inducing remission in both UC and CD
- • No role in maintenance therapy in either UC or CD
- • Once clinical remission is achieved, they should be taper
- Maintenance therapy - Azathioprine and 6-Mercaptopurine
- • Commonly employed in the management of glucocorticoid dependent IBD
- • Promising role as maintenance therapy
Treatment of toxic megacolon?
- Total abdominal colectomy with ileostomy and preservation of the rectum is treatment of choice for toxic megacolonQ.
- It serves the main purpose of removing the diseased colon and avoiding a difficult and morbid pelvic dissectionQ.
Diameter in megacolon?
- Cecum Cecum> 12 cmQ
- Ascending colon> 8 cm
- Transverse colon> 5.5 cmQ
- Rectosigmoid or descending colon> 6.5 cm
Etiology of Megacolon?
- • Congenital or aganglionic megacolon (Hirschprung’s diseaseQ)
- • Medications (antipsychoticsQ)
- • Acquired megacolon
- −−Idiopathic megacolon
- −−Toxic megacolon (UC and pseumembranous colitisQ)
- −−Infection: Clostridium difficileQ
- −−Neurologic, metabolic and Systemic diseases (Chagas disease, ParkinsonismQ)
Stricture in UC?
Inflammation is purely mucosal in ulcerative colitis, strictures are highly uncommon. Any stricture diagnosed in a patient with ulcerative colitis is presumed to be malignant until proven otherwise
Treatment of enterocutaneous fistula?
- Most of these fistulas heal spontaneously within 4–6 weeks of conservative managementQ. If closure is not accomplished after this time, surgery is indicated.
- This period of conservative management not only allows those fistulas to heal spontaneously but also allows for optimization of nutritional status and control of the wound and fistula sitesQ.
- Also, a reasonable delay permits the peritoneal reaction and inflammation to subside, thus making a second operation easier and saferQ.
- Preferred operation: Fistula tract excision and segmental resection of the involved segment of intestine and reanastomosisQ
- Simple closure of the fistula after removing the fistula tract almost always results in a recurrence of the fistula