IBD Flashcards
IBD: peak incidence?
15 - 30, second peak 50 - 80
IBD: environmental factors? gut microbiota?
increased prevalence with western lifestyle: smoking, diet, stress, NSAIDs, infection, early exposure to antibx. IBD pts have dysbiosis = altered gut microbiome
IBD development requires what combined with what? (in terms of host immune response) what TH mediate CD vs. UC?
innate (macrophage/neutrophil) immune responses + acquired (T and B cells) responses + loss of tolerance to enteric commensal bacteria. CD = Th1 and 17. UC = TH2
7 risk factors for IBD?
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.
when to suspect IBD: symptoms (5)? lab tests (4)? last big one?
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!
UC presentation: 3 main symptoms? diagnose early or late?
diagnosed early. diarrhea (bloody and chronic). abdo cramps. urgency/tenesmus/incontinence.
UC: physical exam findings? (6)
mild fever, tachycardia, dehydration, anemia, abdo tenderness, blood on DRE
UC: diagnosis - always exclude? test of choice? confirm with? what else could be helpful
exclude infectious colitis so do C+S, O+P, c diffe. lower endoscopy. confirm with biopsy and histology. radiology can be helpful.
UC endoscopy: disease starts where and goes where? what looks normal? what do you see on radiology?
begins in rectum and progresses proximally. ileum normal. leadpiping, thumb printing but also seen with infectious colitis.
UC disease extent/distribution? importance?
colon only, starts in rectum and extends proximally with no skip lesions. mucosal inflammation only. more extensive = more complications and risk of cancer
UC endoscopic severity, 3 categories
(note normal = crips blood vessels). mild = loss of vascular pattern with granular mucosa. mod = friable mucosa. severe = ulcers, mucopurulent discharge, spont bleeding
UC pathology (3 findings)
distorted and branched crypts. crypt abcesses. plasma cells at crypt base
UC vs. infectious on pathology?
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
complications of UC (4)
toxic megacolon. perforation. stricture. colon cancer.
criteria for toxic megacolon diagnosis
colonic dilation >6 cm + 3 of fever, anemia, HR>120, high neutrophils + 1 of: dehydration, hypotension, altered sensorium or electrolyte distrubance
strictures in UC are ____ unless proven otherwise? other causes of stricture?
malignant (vs. crohn’s where it’s less likely). other causes of stricture than cancer: inflammation/spasm, fibrosis/scar.
development of colon cancer in UC vs. sporadic?
sporadic: APC first, then p53. UC: p53 first then APC
crohn’s presentation. what is uncommon? diagnosed early or late? reasons for diarrhea?
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
4 clinical presentations of crohn’s?
inflammatory. stricturing = obstructive symptoms. penetration (fistulas or perforations). perianal disease = fissures, fistulas, abscesses
crohn’s physical exam findings? (8)
pallor, abdo tenderness, abdo mass, weight loss, malnutrition, low grade temp, EIM, perianal exam - fistula, fissures
test of choice for crohn’s dx? 2 other things to do? always exclude?
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
distribution of crohn’s?
anywhere along GIT and skip lesions. almost always ileum is invovled. “gums to bum”
crohn’s endoscopy appearance? histology? gross pathology?
E: ulcers, strictures. H: GRANULOMAS!!! also aphthous ulcers = earliest sign. G: cobblestoning, creeping fat
granulomas is?
crohn’s!
crohn’s CT appearance?
inflammatory = comb’s sign aka mucosal hyperenhancement where you see blood vessels. fibrostenotic = wall thickening, no engorgement of vasa recta
crohn’s complications (3)
strictures = bowel obstruction. fistulas. perianal fissures.
goals of IBD therapy
induce then maintain steroid freed remission . prevent complications. improve QoL. avoid surgery. mucosal healing.
treatment pyramid (mild first)
mesalamine. corticosteroids. immunosuppressives. biologics. surgery (colectomy with pouch for UC, resection/stricturoplasty/diverting ielostomy for CD)
UC vs cronh’s summary: main characteristics?
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
IBD EIMs
MSK = arthritis, osteoarthropathy (clubbing), osteoporosis. derm = erythema nodosum, pyoderma gangrenosum, aphthous ulcers, nutritional defs. primary sclerosing cholangitis. uveitis.
