Inflammatory Bowel Disease/Carcinoid, Gastrointestinal Stromal Tumor and Lymphoma Flashcards Preview

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Flashcards in Inflammatory Bowel Disease/Carcinoid, Gastrointestinal Stromal Tumor and Lymphoma Deck (45)
1

Inflammatory Bowel Disease

-group of chronic inflammatory conditions of colon and small intestine
-chronic relapsing immune activation and inflammation within the GI tract
-dysregulation of the immune response to GI luminal bacteria

2

2 major forms of IBD

1) Crohn Disease
2) Ulcerative Colitis

3

Environmental Risk Factors for IBD

-cigarette smoking (dec. UC, inc. CD)
-appendectomy (dec. UC, inc. CD)
-high-sanitation level in childhood (inc. CD)
-high-intake refined carbs (inc. CD)

4

"Hygiene Hypothesis"

--incidence of immune-mediated diseases rising in developed countries (related to modern hygiene or lack of exposure)
-Conflicting data in IBD (protective: exposure to pets), or maybe risk factor

5

Ulcerative Colitis

-chronic inflammatory disorder of the GI tract affecting the large bowel, relapsing
-begins in rectum and extends proximally continuously,no skin lesions
-rarely pericolonic abscess
-indolent, relapsing disease
-no skip lesions

6

Ulcerative Colitis: Endoscopically

-hyperemia, edema, granularity with friability, easy bleeding, broad based ulceration, pseudopolyps, tunnels with mucosal bridges, rarely perforation

7

Ulcerative Colitis: Toxic Megacolon

-shutdown of neuromuscular function secondary to exposure of fecal material to muscularis mucosae and neural plexus

8

Ulcerative Colitis: Gross Pathology

-edematous, congested and hemorrhagic mucosa with superficial ulceration and loss of normal folding pattern

9

Ulcerative Colitis: Microscopic Pathology

-edematous congested mucosa with more blue than normal = inflammatory cell nuclei, and with superficial ulceration
-cyrpt "abscesses"

10

Ulcerative Proctitis

-inflammation is confined to the rectum
-rectal bleeding may be the only sign
-rectal pain, feeling of urgency or an inability to move the bowels in spite of the urge to do so (tenesmus)
-this form of ulcerative colitis tends to be mildest

11

Proctosigmoiditis

-involves rectum/sigmoid
-bloody diarrhea, abdominal cramps and pain and tenesmus are common
-continuous

12

Left-sided colitis

-inflammation extends from rectum up the left side through the sigmoid and descending colon
-bloody diarrhea, abdominal cramping and pain on left side, and unintended weight loss
-continuous

13

Pancolitis

-entire colon
-bouts of bloody diarrhea that may be severe, abdominal cramps and pain, fatigue and significant weight loss

14

Fulminant Colitis

-uncommon, life-threatening
-entire colon
-severe pain, profuse diarrhea, dehydration and shock, SIRS
-extensive and deep colonic injury

15

Barium Contrast Studies

-superb instrument to observe fine mucosal detail
-dependent on skill of radiologist
-requires appropriate use of barium, air insufflation, palpation, positioning, compression and use of spot films

16

Ulcerative Colitis: CT

-increasing use in diagnosis
-most sensitive for evaluation of free air (toxic megacolon with perforation)
-See liver, mesenteric inflammation & lymphadenopathy
-CT dosen't show mucosal detail well (may miss subtle changes early in disease that can be seen with air contrast BE and endoscopy

17

Crohn's Disease

-chronic
-involves any location of GI tract
-propensity for distal small bowel & proximal colon
-can involve mouth to anus: apthoid ulcers in mouth, esophageal ulcers, gastric disease, small bowel

18

Main location for Crohn's?

illeum
small intestine alone (30%)
small intestine + colon (40%)
colon alone (40%)

19

Peak age for Crohn's?

20-29

20

Crohn's Colitis

1. asymmetrical disease where there is involvement
2. aphthous ulcers
3. rectal sparing
4. skin lesions
5. deep ulcerations
6. stricture formation
7. fistula
8. disease can be limited to right colon

21

Characteristics of Crohn's?

1. transmural involvement
2. noncaseating granuloma (40-60%)
3. Fissuring with fistula
4. Skip lesions

22

Crohn's Disease: Gross Pathology

-transmural
-"cobblestone" mucosa
-"skip lesions" alternating areas of involved and uninvolved bowel
-"creeping fat" on the serosa extending to seal off areas of transmural inflammation

23

Crohn's Disease: Microscopic Pathology

-fistula
-edema, inflammation w/neutrophils, lymphocytes, plasma cells, eosinophils & macrophages, forming granulomas (35%)
-rarely necrotizing, not as tightly cohesive as sarcoidosis

24

Endoscopy in Crohn's Disease

-ulcerations
-pseudopolyps

25

Gastric & Duodenal Crohn's

-gastric ulcers
-crohn disease in distal antrum & duodenal bulb

26

Crohn's Disease: Radiology

mucosal hyperenhancement and mesenteric hypervascularity
-fistulas

27

Erythema Nodosum: microscopic pathology

-type of panniculitis (inflammation of subcutaneous tissue) with lymphocytes, macrophages and multinucleated giant cells, leading to fibroblastic repair response and fibrosis

28

Pathophysiology of Gastric Carcinoid Tumors

-chronic gastritis or gastric acid suppression
-hypergastrinemia compensatory response
-gastric diffuse neuroendocrine hyperplasia

-comes from neuroendocrine cells

29

Gastric Neuroendocrine Tumor (Carcinoid) Immunostain

+ for chromogranin

30

Gastric Neuroendocrine Tumor

-80% associated with hypergastrinemia, indolent, metastases uncommon (can remove antrum)
-20% not associated with hypergastrinemia, aggressive, many with metastases at diagnosis, associated with carcinoid syndrome

31

Zollinger-Ellison Syndrome: diagnosis


-fasting gastrin level >1000 pg/ml with gastric pH below 5
-secretin stimulation test (gastrin levels 0, 2, 5, 10, 15, 20 min after IV secretin)
-increase in gastrin of >200 pg/ml (100% specific)

32

Treatment of Zollinger-Ellison Syndrome

-surgical resection: solitary, non-metastatic disease
-medical management: high dose PPI, long asting somatostatin analog
-Metastatic disease: streptozocin/doxorubicin or temozolamide
-resection, TACE, RFA, OLT

33

Intestinal Neuroendocrine Tumor (Carcinoid)

-typically late middle-age
-ileum & appendix = common
-multiple sites
-abdominal pain = most frequent symptom
-intermittent obstruction can occur
-most common neoplasm in appendix (1 in 300 appendectomies)
-rectal tumors small, rarely metastatic

34

Carcinoid Syndrome

-episodes of flushing (95%), diarrhea, wheezing, colicky abdominal pain
-right heart endocardial fibrosis (50%)
-10% liver metastases (ileal tumors)
-due to vasoactive polypepptides, serotonin
-high urine 5-hydroxyindole acetic acid (5-HIAA) diagnositc (but limited sen & spec)

35

Colorectal Neuroendocrine Tumors

Colon: more in right colon, usually large mass
Rectum: found incidentally, carcinoid syndrome is rare, prognosis depends on size

36

Gastrointestinal Stromal Tumors (GIST)

-uncommon (5,000/yr in US), older adults
-most common in stomach and small intestine
-derive from or differentaited toward interstitial cells of Cajal, GI pacemaker cells that form the interface b/w autonomic innervation & smooth muscle cells of gut
-most have mutation in KIT transmembrane receptor tyrosine kinase, activating it as an oncogene, with positive immunostain for CD117
-all possibly malignant or malignant

37

GI stromal Tumors (GIST) Presentation

40% with overt GI bleeding
40% with abdominal mass
20% abdominal pain

38

GIST Detection

CT detects, but endoscopy biopsy can be false - b/c they are in the wall, not mucosa
-Endoscopic ultrasound-guided fine needle aspiration has 82% sen and 100% spec
-

39

GIST treatment

surgery, if metastatic, can usually be given tyrosine kinase inhibitor imatinib mesylate

40

Post-Transplant Lymphoproliferative Disorder

-Immunosuppression can allow B cells infected with Epstein-Barr virus to proliferate in an uncontrolled manner
-Blood test for EBV DNA can detect it
-If immunosuppression can be safely decreased, sometimes the proliferation will come under control

41

Gastrointestinal Lymphoma

-Rare ( most of the rest aggressive diffuse large B-cell lymphomas

42

GI Lymphoma Presentation

-epigastric pain (93%)
-anorexia (47%)
-weight loss (25%)
-occult bleeding (19%)
-nausea/vomiting (18%)

43

GI lymphoma diagnosis

endoscopy with biopsy

44

GI lymphoma treatment

antibiotics for MALToma
radiation/chemo for other types

45

GI lymphoma prognosis

good for MALToma
bad for other types