IBD

Question 1

IBD: peak incidence?

Answer 1

15 - 30, second peak 50 - 80

Question 2

IBD: environmental factors? gut microbiota?

Answer 2

increased prevalence with western lifestyle: smoking, diet, stress, NSAIDs, infection, early exposure to antibx. IBD pts have dysbiosis = altered gut microbiome

Question 3

IBD development requires what combined with what? (in terms of host immune response) what TH mediate CD vs. UC?

Answer 3

innate (macrophage/neutrophil) immune responses + acquired (T and B cells) responses + loss of tolerance to enteric commensal bacteria. CD = Th1 and 17. UC = TH2

Question 4

7 risk factors for IBD?

Answer 4

Age (15-40, 50-80). more common in jews, less in hispanics/blacks. Fam history (15-20% FDR). smoking (UC after quitting). appendectomy protective. western diet. NSAIDs.

Question 5

when to suspect IBD: symptoms (5)? lab tests (4)? last big one?

Answer 5

diarrhea, abdo pain, weight loss, gross failure, rectal bleeding, EIM. anemia, iron def, raised inflamm blockers CRP + ESR. low albumin. micronutrient defs: B12, zinc, selenium. FAM HX!

Question 6

UC presentation: 3 main symptoms? diagnose early or late?

Answer 6

diagnosed early. diarrhea (bloody and chronic). abdo cramps. urgency/tenesmus/incontinence.

Question 7

UC: physical exam findings? (6)

Answer 7

mild fever, tachycardia, dehydration, anemia, abdo tenderness, blood on DRE

Question 8

UC: diagnosis - always exclude? test of choice? confirm with? what else could be helpful

Answer 8

exclude infectious colitis so do C+S, O+P, c diffe. lower endoscopy. confirm with biopsy and histology. radiology can be helpful.

Question 9

UC endoscopy: disease starts where and goes where? what looks normal? what do you see on radiology?

Answer 9

begins in rectum and progresses proximally. ileum normal. leadpiping, thumb printing but also seen with infectious colitis.

Question 10

UC disease extent/distribution? importance?

Answer 10

colon only, starts in rectum and extends proximally with no skip lesions. mucosal inflammation only. more extensive = more complications and risk of cancer

Question 11

UC endoscopic severity, 3 categories

Answer 11

(note normal = crips blood vessels). mild = loss of vascular pattern with granular mucosa. mod = friable mucosa. severe = ulcers, mucopurulent discharge, spont bleeding

Question 12

UC pathology (3 findings)

Answer 12

distorted and branched crypts. crypt abcesses. plasma cells at crypt base

Question 13

UC vs. infectious on pathology?

Answer 13

infection = quick onset, <2 weeks, normal Hb/platelets, and see neutrophils and straight crypts. UC = insidious onset > 4 week, low Hb and high platelets. also see branched crypts and mixed infiltrate. note both can have abscesses

Question 14

complications of UC (4)

Answer 14

toxic megacolon. perforation. stricture. colon cancer.

Question 15

criteria for toxic megacolon diagnosis

Answer 15

colonic dilation >6 cm + 3 of fever, anemia, HR>120, high neutrophils + 1 of: dehydration, hypotension, altered sensorium or electrolyte distrubance

Question 16

strictures in UC are ____ unless proven otherwise? other causes of stricture?

Answer 16

malignant (vs. crohn’s where it’s less likely). other causes of stricture than cancer: inflammation/spasm, fibrosis/scar.

Question 17

development of colon cancer in UC vs. sporadic?

Answer 17

sporadic: APC first, then p53. UC: p53 first then APC

Question 18

crohn’s presentation. what is uncommon? diagnosed early or late? reasons for diarrhea?

Answer 18

RLQ pain. diarrhea. iron def/anemia. fever. weight loss/growth failure. fatigue. gross bleeding uncommon. often diagnosed late. diarrhea from: inflamm, bile loss because ileum is involved, bacterial overgrowth

Question 19

4 clinical presentations of crohn’s?

Answer 19

inflammatory. stricturing = obstructive symptoms. penetration (fistulas or perforations). perianal disease = fissures, fistulas, abscesses

Question 20

crohn’s physical exam findings? (8)

Answer 20

pallor, abdo tenderness, abdo mass, weight loss, malnutrition, low grade temp, EIM, perianal exam - fistula, fissures

Question 21

test of choice for crohn’s dx? 2 other things to do? always exclude?

Answer 21

colonoscopy and intubation of ileum. gastroscopy for UGI involvement. small bowel assessment (follow through, MR/CT, capsule endoscopy, balloon endoscopy). always culture stool to exclude infectious colitis

Question 22

distribution of crohn’s?

Answer 22

anywhere along GIT and skip lesions. almost always ileum is invovled. “gums to bum”

Question 23

crohn’s endoscopy appearance? histology? gross pathology?

Answer 23

E: ulcers, strictures. H: GRANULOMAS!!! also aphthous ulcers = earliest sign. G: cobblestoning, creeping fat

Question 24

granulomas is?

Answer 24

crohn’s!

Question 25

crohn’s CT appearance?

Answer 25

inflammatory = comb’s sign aka mucosal hyperenhancement where you see blood vessels. fibrostenotic = wall thickening, no engorgement of vasa recta

Question 26

crohn’s complications (3)

Answer 26

strictures = bowel obstruction. fistulas. perianal fissures.

Question 27

goals of IBD therapy

Answer 27

induce then maintain steroid freed remission . prevent complications. improve QoL. avoid surgery. mucosal healing.

Question 28

treatment pyramid (mild first)

Answer 28

mesalamine. corticosteroids. immunosuppressives. biologics. surgery (colectomy with pouch for UC, resection/stricturoplasty/diverting ielostomy for CD)

Question 29

UC vs cronh’s summary: main characteristics?

Answer 29

UC = continuous and only in colon with rectal involvement and bleeding. mucosal disease, no granulomas, rare to have EIM, strictures, fistulas. CD = skip lesions and involves small bowel, rectal sparing and rare rectal bleeding. transmural disease. see granulomas, strictures, fistulas and common to see EIM

Question 30

IBD EIMs

Answer 30

MSK = arthritis, osteoarthropathy (clubbing), osteoporosis. derm = erythema nodosum, pyoderma gangrenosum, aphthous ulcers, nutritional defs. primary sclerosing cholangitis. uveitis.