Inflammatory bowel disease Flashcards
Which part of the colon wall do the different types of IBD affect?
- Ulcerative colitis: Only mucosa
2. Crohn’s: Transmural
What are other colitides?
- Microscopic colitis
- Diversion colitis (colon excluded)
- Diverticular colitis
- Pouchitis
Which part of the GI tract does UC/Crohn’s affect?
UC: Colon alone
Crohn’s: Any part of the GI tract
Which has skip lesions, UC or Crohn’s?
Crohn’s. In contrast, UC starts in the rectum, then progresses proximally up the bowel
Which has surgery as an option, UC or Crohn’s?
UC b/c it only involves the colon
Which has perianal disease, UC or Crohn’s?
Crohn’s
Which has more complications (strictures, fistulas, abscesses?) UC or Crohn’s?
Crohn’s
What’s the difference in mucosal histology between the small intestine and colon/rectum?
Small intestine: Paneth cells at the bottom of Villi, and mucosal lymphatics (Where MALT arises)
Colon/rectum: Flat surface and pericrypt fibrous sheath
What do you see in histology of active ulcerative colitis?
Intense, diffuse inflammatory infiltrate with ulceration of the surface epithelium
When are Crohn’s and UC typically diagnosed?
Onset at any age, but peak incidence in late adolescence/early adulthood
Is IBD more common in males or females?
even
which parts of the world do you see more IBD?
North america and europe
Which has a stronger genetic susceptibility, CD or UC?
Crohn’s disease
What is the association between cigarette smoking and inflammatory bowel disease?
Smoking is protective against UC
Smoking increases risk against CD
What other risk factors are there for UC?
Appendectomy decreases risk of UC
What other risk factors are there for CD?
Increased risk with:
- High sanitation
- Higher with refined carbs and perinatal infection
What is the general theroy behind the pathogenesis of IBD?
- Genetic susceptibility (HLA B27, after environmental trigger, will lose tolerance leading to chronic inflammation)
- Luminal antigens (Microbiome)
- Environmental triggers
Lactobacillus is protective. Bacteroides vulgatus, and cecal bacteria alone cause colitis
What are some examples of environmental triggers for IBD?
- antibiotics
- diet
- acute infections
- NSAIDs
- Smoking
- Stress
What is the typical pattern of ulcerative colitis?
- Colon only
- Mucosal inflammation
- Continuous distribution
- Rectal involvement
What are the sx of ulcerative colitis?
- Rectal bleeding (hematochezia)
- Diarrhea
- Abdominal pain
- Tenesmus
- Systemic symptoms
- Extraintestinal manifestations
What are the criteria for mild, moderate, and severe ulcerative colitis?
- Mild:
- 4 stools/day, minimal systemic disturbances - Severe disease
- >6 stools/day, with blood
- Systemic dz with fever, tachy, and anemia
How do you diagnose UC?
- Clinically + endoscopic appearance + histology of biopsy
What are the different ways in which ulcerative colitis can present?
- Recurring episodes of mild/moderate severity
- Fulminating (severe)
- Chronic active (smoldering, consistent dz)
- Proctitis (remains localized in rectum)
What are the complications of ulcerative colitis?
- Massive hemorrhage
- Toxic megacolon
- Perforation
- Colon cancer (20x)
Describe the progression of cancer in IBD and contrast it with non-IBD
IBD: Inflammation leads to dysplasia then cancer
Non-IBD: Formation of a single polyp leading to cancer
What is a third category of inflammatory bowel disease? How does it present?
Microscopic colitis. Presents with watery, non-bloody diarrhea. Colonic mucosa looks normal on endoscopy but shows microscopic inflammation
What are the two types of microscopic colitis? Differences between the two?
Collagenous and lymphocytic colitis
- Lymphocytic more associated with celiac dz
- collagenous associated with older women with subepithelial layer of collagen
What are the complications of Crohn’s disease?
- Obstruction from edema of transmural inflammation
2. fistulization with the creation of sinus tracts
What are additional distinguishing features of crohn’s disease?
Ulcerative colitis always as bloody stool
Crohn’s disease has 30% of pts with no blood
Also, fistulization occurs only in crohn’s
Granulomas as PATHOGnomonic for Crohn’s dz, with multinucleated giant cells and lymphocytes in the periphery
Describe the distribution of affected areas in Crohn’s disease
- Small bowel only=33%
- Ileocolic=45%
- Colon=20%
What does Crohn’s disease look like on endocscopy?
Lots of nodules, exudate. “cobblestoning” with long longitudinal/transverse ulcerations.
If obstructed, will look like a “string of sausages”
Where does pain show up in Crohn’s dz? Why?
LRQ b/c most of the inflammation is in the ileocecal region
What could make Crohn’s disease look like appendicitis?
Localized microperforation can irritate the peritoneum just like an enlarged appendix
What are symptoms of obstruction in Crohn’s?
Post-prandial cramps and distention
Vomiting and weight loss from food avoidance
What are the symptoms with each of the following types of fistulizations?
- Enteroenteric
- Enterovesical
- Retroperitoneal
- Enterocutaneous
- Perianal
- Rectovaginal
- Asymptomatic
- Recurrent UTIs
- Psoas sign with back, hip/thigh pain
- Drainage
- pain and drainiage (can’t sit down!) “elephant ear”
- Drainage of feces or air
How does IBD present in the child?
- Fever
- Anemia
- Arthritis
- Failure of growth/development
What are the extraintestinal manifestations of IBD?
- Aphthous stomatitis
- Episcleritis/uveitis
- Arthritis
- E nodosum and P gangrenosum
- Vascular complications
How is the peripheral arthritis of IBD different from rheumatoid arthritis?
- Affects the large joints (foot, knee, wrist)
- No synovial destruction
- No nodules
- seronegative
- asymmetric and monoarticular
