Inflammatory Bowel Disease

Question 1

What is IBD?

Answer 1

loss of tolerance against indigenous enteric flora believed to be central event in pathogenesis of IBD

Question 2

What 2 things can IBD be triggered by? What makes it worse?

Answer 2

1. increased intestinal permeabililty
2. imbalanced microflora
3. psychological stress exacerbates the condition

Question 3

What Crohn’s dz? What type of destruction is there? What kind of appearance does this lead to? What develops with progression? Typical pattern?

Answer 3

chronic transmural inflam of colon involving mesentery as well as regional LNs, may involve the entire GI tract w/”skip lesions”
early mucosal involvement= aphthous ulcerations which is responsible for cobblestone appearance
with progression get deep fissures, sinuses & fistulas
typical pattern= intermittent exacerbations & periods of remission, worse w/stress

Question 4

Etiology & RFs of Crohn’s?

Answer 4

UNKNOWN
mb genetic, infectious, immunologic, psychological factors possible
smoking
use of oral contraceptives
diet of dairy, refined sugar, low fiber, high animal fat
dysbiosis, dt abx
removal of inflamed appendix early in life

Question 5

Epidemiology of Crohn’s?

Answer 5

bimodal distribution, early peak 15-25 yo, smaller peak 55-65 yo
pts 40
jewish pop 2-4x’s more likely, high in caucasians
increased in higher socioeco groups & type A personality
slight predominance in females

Question 6

Pathophys of Crohn’s?

Answer 6

inflam involves all layers of intestinal wall which becomes thick patchy distribution w/areas of normal bowel (“skip lesions”)
can occur from mouth to anus
rarely affects stomach, duodenum & esophagus

Question 7

Ssxs of Crohn’s? what is perianal dz?

Answer 7

abd pain, stead, RLQ, fatigue
occult blood, blood in stool if colon involvement
stool usu formed but can be lose with colonic involvement or terminal ileum, steatorrhea, 1/3 have perianal dz (fissures, fistulas, perianal abscesses)

Question 8

What are the 4 patterns of Crohn’s that can present?

Answer 8

1. inflammation: RLQ pain, tender
2. obstruction: severe colic, abd distention, constipation, vomiting
3. diffuse jejunoileitis: inflam & obstruction which leads to chronic debility
4. abd fistulas & abscesses: usu late w/fever, painful masses & wasting

Question 9

PE of Crohn’s?

Answer 9

RLQ tenderness w/assoc fullness or mass

abd distention, fever, wt loss

Question 10

4 complications of Crohn’s? what can they all lead to?

Answer 10

1. intestinal obstruction, reversible early, as progresses though can lead to constipation & intractable obstruction from fixed luminal narrowing
2. fistula formation is common and can cause abscesses, malabsorption, cutaneous fistula, persistent UTIs, pneumaturia
3. perforation
4. hemorrhage
   3&4 dt thickened mucosa
   *increase risk of SCC

Question 11

Labs for Crohn’s?

Answer 11

CBC: mild anemia, leukocytosis
increased ESR, elevated CRP
low serum iron, low vit B12
positive fecal lysozyme
ASCA (higher in Crohn's), ANCA (higher in UC)

Question 12

Imaging for Crohn’s? What do you see in advanced cases?

Answer 12

xray, double-contrast barium enema exam
single-contrast upper GI series w/small-bowel follow through barium xray= irregularity, nodularity, stiffness, thickening of terminal ileum, narrowed ileum lumen
advanced cases: string sign= marked stricture of the ileum

Question 13

What will a colonoscopy show?

Answer 13

“skip areas” “cobblestone appearance,” longituidinal ulcers, rectal sparing, narrowing & fistulas

Question 14

1/2 of pts have what pathognomonic sign?

Answer 14

sarcoid-type epitheloid granulomas in the intestinal wall & occ in involved mesenteric nodes

Question 15

DDX of Crohn’s?

Answer 15

lactose intolerance, IBS, infectious colitis, UC, appendicitis, diverticulitis, carcinoma

Question 16

What is ulcerative colitis? what is ulcerative proctitis?

Answer 16

chronic, recurrent inflam dz of the colon or rectal mucosal layer w/superficial ulcertion
almost always involves the colon (NO skip areas)
ulcerative proctitis= UC localized to the rectum, common

Question 17

Etiology & RFs of UC? What chromosomes? what is negatively assoc?

Answer 17

immune-mediate (abn humoral & cell-mediated immunity &/or enhanced reactivity against bac antigens
chromosomes 12 & 16 are factors & genetic susceptibility, FHx may play a role
smoking is negatively assoc w/UC (opposite in Crohn’s)
mb environmental factors
dietary factors: dairy, refined sugar, low fiber, high animal fat

Question 18

Epidemiology/incidence of UC?

Answer 18

2-4 x’s higher in Jewish pop & higher in whites
slight predominance in males
peaks 15-25 yo & 55-65 yo (but any age can have it)

Question 19

Ssxs of UC? if only in recto-sigmoid area? if extends proximally? systemic sxs?

Answer 19

ranges from mild to severe
cramping abd pain
series of attacks of bloody diarrhea w/asx intervals
begins insidiously w/increased urgency, lower abd cramps, blood & mucosa
if in recto-sigmoid only stool mb normal, hard or dry w/rectal d/c of WBCs & RBCs
if extends proximally stools are looser, 10-20/d w/severe cramps, rectal tenesmus, watery stools w/pus, blood & mucus
systems sxs: malaise, fever, anemia, wt loss

Question 20

3 complications of UC? most common? most serious? most progressing?

Answer 20

hemorrhage most common!
TOXIC MEGACOLON- distended colon w/attenuated walls & immediate danger of perforation!!! may occur in severe colitis (>40% mortality)
cells can become dysplastic w/increased risk of colon CA, 0.5-1% increase each year

Question 21

Labs for UC?

Answer 21

CBC- anemia, plts >350,000/mL
elevated ESR & CRP
CMP- hypoalbuminemia, hypokalemia, hypomagnesemia, elevated alk phos
stool analysis for organisms (salmonella, shigella, E. coli, etc)

Question 22

Imaging for UC? xray? barium enema? what 2 can provide a dx?

Answer 22

xray might show colonic dilation in severe cases suggesting TOXIC MEGACOLON, also evidence of perforation, obstruction or ileus
barium enemas for mild cases, narrow, tubular, shortened colon w/loss of haustral folds, pseudopolyps & small ulcers
flexible sigmoidoscopy can provide diagnosis!!!
colonoscopy w/bx confirms dx also useful for documenting extend of dz but do with caution b/c of risk of perforation

Question 23

Prognosis of UC?

Answer 23

controlled w/tx, usu lifelong exacerbations & remissions, severe cases need surgery

Question 24

Extra-intestinal manifestations of IBD?

Answer 24

peripheral arthritis, erythema nodosum, conjunctivitis, fatty liver, pyelonephritis, amyloidosis

Question 25

Crohn’s specific extra-intestinal manifestations of IBD?

Answer 25

cholelithiasis, renal oxalate stones, vit B12 deficiency, obstructive hydronephrosis, aphthous ulcers