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Flashcards in GI Deck (134):
1

Pleomorphic adenoma (gland)

Mixed epithelial and stroma tumor usually in parotid; benign but has high rate of recurrence and is associated with radiation

2

Warthin's tumor

Benign heterotopic salivary gland tissue trapped ina lymph node, surrounded by lymphatic tissue

3

Mucoepidermoid carcinoma

Most common malignant tumor of salivary glands; usually located in the sublingual gland (most parotid tumors are benign while most sublingual are malignant)

4

Zenker diverticulum

Above upper esophogeal sphincter; risk for adenocarcionma

5

Traction diverticulum

midpoint of esophagus; risk for adenocarcinoma

6

Epiphrenic diverticulum

immediately above lower esophageal sphincter

7

Acute gastritis histology

neutrophils above BM, loss of surface epithelium, fibrin-containing purulent exudate

8

Chronic gastritis histology

lymphoid cell aggregates in lamina proria, columnar absorptive cells, atrophy of glandular structures

9

Zollinger ellison syndrome histology

Thickening of gastric folds, elevated gastrin levels, glandular hyperplasia

10

Drugs promoting gastric motility

Cholinergic agonists (bethanechol), acetylcholinesterase inhibitor like neostigmine, Metoclopramide (5HT agonist and Dopamine antagonist - potential for seizures), Macrolides (stimulate smooth muscle receptors)

11

tubular adenomas

pedunculated and smaller; dysplastic colonic mucosal cells that form tubular-shaped glands

12

Villous adenomas

cauliflower or fingerlike projections; dysplastic epithelial cells forming villi-like projections; can cause bleeding, secretory diarrhea and partial intestinal obstruction. Are larger sessile and more severely dysplastic than tubular; high risk of progression to adenocarcinoma

13

Tubulovillous adenoma

mixture of villous and tubular histology

14

Hamartomatous polyp

can occur sporadically or as part of Peutz-Jeghers syndome and Juvenile polyps. Can cause bleeding and intussusception but not diarrhea.

15

Peutz-Jeghers syndrome

associated with multpiple hamartomatous polyps and black spots on skin and mucosa of young patients. Secretory diarrhea is not common in this condition. Rare compared to adenomatous polyps; increased risk of CRC

16

Signet ring cell carcinoma can be found here

stomach, breast, ovary, colorectal area.

17

Treatment for acute arsenic poisoning

Dimercaprol - displaces arsenic from sulfydryl groups

18

Treatment of choice for Mercury and lead poisoning

EDTA which complexes with mono-, di- and trivalent ions

19

Secretin

Duodenal S cells release secretin in response to H+; stimulates pancreatic cells to increase bicarb secretion; As pancreatic juice flow rates and secretin stimulation increase the bicarb concentration increases and Cl concentration decreases

20

Curling ulcer

ulcers arising in proximal duodenum assoc with severe trauma or burns.

21

Cushing ulcer

esophageal, stomach, or duodenal ulcers associated with high intracranial pressure. Due to to impaired oxygenation of tissues, induced by vagus stimulation from brain resulting in hypersecretion.

22

Two subtypes of gastric adenocarcinoma

Intestinal: intestinal glands similar to colonic adenocarcinoma; Diffuse: signet-ring cells. Gastritis, barrett esophagus, H pylori, nitrate consumption, diet lacking in fruit and vegetables, cigarette smoking are risk factors

23

Opioid side effects on GI system

Constriction of sphincter of Oddi which can cause increase in common bile duct pressure. Cause histamine release leading to vasodilation and itching. Cause constipation by slowing motility, decrease parietal cell acid secretion, can indirectly increase somatostain secretion.

24

Duodenal ulcer associateions

pain decreased with meals. Almost always H pylori. Some have increased gastric acid secretion as in ZE syndrome. Hypertrophy of Brunner's glands. NOT assoc w risk of carcinoma (esophageal, gastric and colonic ulcers are)

25

Duodenal ulcer location

Most occur in duodenal bulb; when found in distal duodenum or other atypical locations Zollinger-Ellison syndrome is suspected. Multiple ulcers, ones refractory to therapy also.

26

Midgut embryology; timing and potential problems

6th week midgut herniates (allows for rapid growth of intestine and liver despite slower growth of abdominal cavity). 10th week 270degree turn counterclockwise around SMA. If this is abnormal, malrotation occurs and cecum is found in RUQ, fixed fibrous bands to second portion of duodenum. Obstruction occurs dt bands which compress duodenum which results with bilious vomiting. Twisting around SMA can also cause midgut volvulus with intestinal gangerene.

27

VIP

produced by pancreatc islet cells and neurons in GI mucosa. Relaxes smooth m, inhibits H+ secretion, stimulates pancreatic bicarb and chloride secretion.

28

CCK

increases secretion of Pancreatic enzymes and contraction of gall bladder, inhibits gastric emptying. Produced by I-cells of proximal small bowel mucosa in response to fatty acids and monoglycerides

29

Secretin

produced by S-cells in respnse to duodenal acidity and fatty acids. Increases pancreatic and biliary bicarb secretion and decreases gastric acid secretion

30

Gastrin

G-cells in stomach mucosa. Stimulates gastric acid production and growth of gastric mucosa, gastrinomas classically cause intractable peptic ulcer disease

31

Glucagonoma

pancreatic alpha-cell tumor that hypersecretes glucagon. Secondary diabetes mellitus and necrolytic migratory erythema of the skin

32

Ulcerative colitis associated carcinoma differs from sporadic how

affects younger patients; progresses from flat non-polypoid dysplasia; appears mucius or has signet ring morphology; early p53 but late APC gene mutation, opposite of sporadic; distributed within proximal colon; multifocal in nature.

33

Amatoxins (death cap mushroom toxins)

Bind to DNA-dependent RNA polymerase II and halt mRNA synthesis. Results in apoptosis of hepatic cells.

34

Modes of transmission of campylobacter versus shigella

Both are fecal-oral but campylobacter is carried by domestic animals where shigella is not. Campylobacter is mostly acquired from animals or undercooked poultry or unpasteurized milk.

35

Somatostatin

made in a bunch of different locations such as hypothalamus, stomach, intestine, and pancreas. It inhibits GH, TSH, and suppresses all other GI hormones

36

Why is shigella's Infective dose so low?

it is resistiant to acid and bile, it also binds to intestinal mucosal M cells on peyer's patches. Other organisms with small infective inoculum are Campylobacter, Entamoeba histolytica (it takes only 1), Giardia (only 1 needed)

37

GERDs typical cause

LES transient relaxation. Acidic gastric contents reflux back into esophagus and irritate mucosa leading to inflammation. Presents with nocturnal cough many times. Biopsy shows basal cell hyperplasia, elongation of lamina propria and inflammatory cells (eosiniphils, neutrophils, lymph)

38

Anal fissure

tear in the lining of anal canal distal to the dentate line that occurs most often on the posterior midline (this area is poorly perfused making it sensitive to trauma by hard fecal mass). Patients complain of severe tearing pain with passage of bowel movements. Assoc w low fiber and constipation.

39

Typical signs of lead poisoning

Colicky abdominal pain "lead colic", constipation, headaches, impaired short-term memory, blue pigmentation at gum-tooth line "lead lines"; wrist drow or foot drop due to peripheral neuropathy; microcytic hypochromic anemia and basophilic stippling

40

CEA

serum carcinoembryonic antigen, marker for colon cancer. It is a glycoprotein involved in cell adhesion. Produced in the embryonic pancreas.

41

Leptin action

produced in adipocytes; decreases food intake by decreasing production of neuropeptide Y (an appetite stimulant in arcuate nucleus); stimulates POMC in arcuate nucleas which is cleaved to MSH which inhibits food intake.

42

Erosions versus ulcers

erosive gastritis: caused by NSAID use, trauma, burns, alcohol or tobacco, stress, bacteria. Defined as mucosal defects that don't penetrate the muscularis mucosa. Ulcers extend into submucosal inner muscular and outer muscular layers.

43

hyperplastic polyp

well-differentiated mucosal cells that form glands and crypts

44

Hamartomatous polyp

mucosal glands, smooth muscle and CT. May be sporadic or in Peutz-Jeghers or juvenile polyposis.

45

Inflammatory polyps

seen in IBD. Composed of regenerating intestinal mucosa

46

Lymphoid polyps

found in children and consist of intestinal mucosa infiltrated with lymphocytes

47

Malignant potential of adenomatous polyps (adenomatous polyps are the ones that contain dysplastic cells that can transform into carcinoma)

Degree of dysplasia, villous histology, size >1cm

48

Imperforate anus

abnormal development of anorectal structures; most often associated with urorectal, urovesical, or urovaginal fistulas. When a fistula is present, meconium may discharge from the urethra or the vagina. Associated findings are renal agenesis, hypospadias, epispadias, and bladder extrophy.

49

Intestinal atresia

occurs due to vascular accidents in utero. If the SMA is obstructed the "apple-peel" atresia occurs. It manifests as blind-ending proximal jejunum with absence of a long length of small bowel and dorsal mesentery. The terminal ileum distal to the atresia assumes a spiral configuration around an ileocolic vessel.

50

Crohn's disease molecular pathogenesis

NF-kB is responsible for the cytokine production seen. NOD2 gene (expressed in epithelial cells and leukocytes) appears to act as microbial receptor that triggers NF-kB. NF-kB induces cytokines in response to infectious pathogens. The NOD2 mutation increases NF-kB allowing intracellular microbes persisting and inducing chronic inflammation within GI tract

51

Fibrosis of islets of pancreas

DM type I

52

pacnreatic ducts filled with mucus plugs

Cystic fibrosis

53

Lymphocytic infiltration of islets of langerhans

DM type 1

54

Lipid digestion

occurs in duodenum and is ABSORBED in the Jejunum.

55

Complications of Ulcerative colitis

Sclerosing cholangitis, CRC, Toxic Megacolon (presents with bloody diarrhea, fever, signs of shock; perforation is a life-threatening complication of megacolon, do not do any barium or contrast studies for fear of perforation)

56

Complications of Crohn's

Strictures, fistulas, perianal disease, CRC

57

Esophageal squamous carcinoma risk factors

alcohol, tobacco smoking, nitroso containing foods; asian and african descent

58

Esophageal adenocarcinoma risk factors

Barrett esophagus, obesity, GERD, tobacco use

59

Vitelline duct abnormalities

Persistent vitelline duc, meckel diverticulum, viteline sinus, and vitelline duct cyst. This normally obliterates during week 7. Also called omphalomesenteric duct

60

esophageal varices

shunt involving Left gastric vein and esophageal vein

61

Caput medusae

Paraumbilical veins to superficial and inferior epigastric

62

Hemorrhoids in ascites

Superior rectal veins to middle and inferior rectal veins which drain into interna linguinal vein

63

acute interstitial pancreatitis pathyphys

stasis of secretions leads to lipase autodigestion and calcium doposition onto free FA's. Pancreas looks edematous with focal fat necrosis and calcium. If the inflammatory process continues it can lead to necrosis.

64

Acute Necrotic pancreatitis

If inflammation from acute interstitial pancreatitis continues the edema cuts off blood supply rendering ischemic damage to acinar cells leading to inappropriate trypsin activation. The trpsin ten activates other proteoltic enmes and initiates autodigestion. The areas of white chaly fat necrosis can spread onto mesentery, omentum etc.

65

Chronic Gastritis Types A and B

Type A is Autoimmune etiology and is found in the body (pernicious anemia); Type B is bacterial in nature (h pylori) and is found in the Antrum

66

adenocarcinoma biopsy and colonoscopy findings

protuberant mass on scope; mucosal cells with gland formation on biopsy

67

colonic CMV scope and biopsy

ulcers and mucosal erosions on scope; Inclusion bodies on micro

68

Colonic cryptosporidium scope and microscopy

scope shows generalized inflammation; basophilic clusters are seen on surface of intestinal mucosal cells

69

Entamoeba histolytica scope and microscopy

scope shows flask shatped ulcers; trophozoites have red blood cells

70

Kaposi's sarcoma scope and microscopy

Reddish violet flat maculopapular lesions or hemorrhagic nodules; the microscopy shows spindle-shaped tumor cells with small-vessel proliferation

71

MSH2 gene

mutated in HNPCC and is responsible for DNA mismatch repair

72

APC gene

located on Chromosome 5 responsible for regulation of growth and cell adhesion

73

Systemic mastocytosis

abnormal proliferation of mast cells and increased histamine secretion. This causes many systemic effects mediated by histamine. In the GI system it leads to increased secretion of Gastric acid

74

Histamine action on parietal cells

H2 receptor stimulates cAMP and PKA

75

Acetylcholine action on parietal cells

M3 receptors leads to increased calcium via IP3

76

Gastrin action on parietal cells

increase of intracellular calcium. It stimulates histamine synthesis and release by enterochromaffin-like cells which is most potent mechanism

77

Risk factor for gallstone ileus

usually in patients with long history of gallstones, a long standing stone creates a fistula between gallbladder and adjoining gut tissue which allows passage into small bowel. This allows for gas to be let into the gallbladder. The gallstone blocks the ileocecal valve and you can see air in the biliary tree

78

CREST

Calcinosis, Raynaud, Esophageal dysmotility, Sclerodactyly, Telangiectasia

79

Factors recucing gastric secretion after a meal

peptide YY to block histamine release, Somatostatin, and prostaglandins

80

Vitamins deficient after gastrojejunostomy

B12, Iron, folate, and fat-soluble vitamins

81

Most common locations of colonic masses

rectosigmoid colon > Ascending colon > Left sided tumors (infiltrate wall of colon and narrow lumen)

82

Causes of acute pancreatitis

Gallstones and alcohol are most common; less common are ERCP procedure, drugs, infection, hypertriglyceridemia, structural abnormalities, surgery, hypercalcemia

83

Spcific antibodies for celiacs

anti-tissue transglutaminase; IgA endomysial antibody

84

Gastric adenocarcinoma, two types

Signet-ring carcinoma: cells don't form glands, diffuse involvement of stomach wall, have plaque appearance, infiltrate large areas of stomach creating leather-bottle stomach (linitis plastica). Intestinal-type adenocarcinoma: resmbles colon cancer, grows nodular polypoid and well-demarcated masses. Most important prognostic factors is depth of invasion and regional lymph. Nitrosamines, achlorhydria, chronic gastritis are risk factors so is type A blood

85

Retroperitoneal Structures

Abdominal Aorta, Pancreas, Descending and ascending colon, Spleen, Ureters, Suprarenal gland, kidney, IVC, deodenum (2nd 3rd and 4th parts), esophagus, rectum

86

Falciform ligament

Attaches liver to anterior abdominal wall

87

Hepatoduodenal ligament

Contains portal triad. Connects greater and lesser sacs

88

Gastrohepatic ligament

Lesser curvature to liver. Contains R and L gastric artery, separates greater and lesser sacs.

89

Gastrocolic ligament

Contains gastroepiploic arteries, part of greater omentum. Attaches to greater curvature.

90

Gastrosplenic ligament

contains short gastric arteries, separates left greater and lesser sac

91

Splenorenal ligament

Connects spleen to posteriosterior abdominal wall, holds splenic artery and vein

92

Normal epithelium of esophagus

stratified squamous nonkeratinized

93

Stomach epithelium

gastric glands

94

Duodenal histology

Villi and microvilli. Brunner's glands, Crypts of Leiberkuhn

95

Jejunum histology

plicae circulares and crypts of lieberkuhn

96

Ileum histology

Peyer's patches, plicae circulares, crypts. Largest number of goblet cells (goblet cells increase density as you mover farther down the ileum)

97

Colon Histology

Crypts but NO villi

98

Layers of digestive tract anatomy

Epithelium (columnar), lamina propria, muscularis mucosa, submucosa with glands and meissner's plexus, Muscularis externa with auerbach's plexus then serosa

99

Name branches and location of branches of abdominal aorta descending order

Inferior phrenic aa., Celiac trunk (T12), SMA (L1), L suprarenal a. (L1), R and L renal aa. (L1-L2), R and L testicular (ovarian) aa. (L2/3), IMA (L3), Bifurcation of aorta L4.

100

Branches of the celiac trunk

L gastric, Spleenic, Common hepatic.

101

Rectum above pectinate line, pathology and venous drainage

Adenocarcinoma, supplied from Superior rectal artery (IMA). Drains to Superior rectal vein and to IMA, then to portal system

102

Rectum below pectinate line

Somatic innervation so hemorrhoids are painful. Drains to inferior rectal vein to internal pudendal then internal iliac to IVC. Squamous cell carcinoma and supplied arterially from Internal pudendal.

103

Indirect Inguinal hernia

More common in males, happens in infants owing to failure of processus vaginalis to close (can form hydrocele). Covered by all 3 layers of spermatic fascia

104

Direct inguinal hernia

Through hesselbach's triangle (inferior epigastric, lateral rectus abdominis, inguinal ligament). Goes through superficial inguinal ring only covered by external spermatic fascia and is seen in older men.

105

Femoral hernia

Protrudes below inguinal ligament, is a common cause of bowel strangulation. Through the femoral canal below and lateral to pubic tubercle. More common in women

106

Gastrin

G cells (antrum); gastric mucosa growth, motility, H+; stomach distention or pH increase, amino acids, peptides, vagal.

107

CCK

I cells (duodenum jejunum) stimulated by FA's and Protein, increases pancreas secretion (via stimulation of parasympathetics), gallbladder contraction, increased sphincter of oddi relaxation, decrease emptying

108

Secretin

S cells (duodenum) increases HCO3 from pancreas, decreases gastric acid secretion, increased by acid and fatty acids.

109

Somatostatin

D cells (pancreas, GI mucosa); decreases all GI hormones, inhibits release of GH and TSH. Increased by acid and decreased by vagal stimulation.

110

GIP

K cells (duodenum jejunum) increases insulin release and decreases H+ secretion. Stimulated by oral glucose (more rapid than glucose given IV)

111

VIP

Parasympathetic ganglia increases secretions and relaxes intestinal smooth m. adecreased by adrenergic input

112

Motilin

Small intestine Produces migrating motor complexes, increased in fasting state

113

Glucose and galactose absorption

SGLT1 (Na dependent)

114

GLUT-5

Fructose transporter in intestine

115

D-xylose test

distinguishes GI mucosal damage from other causes of malabsorption

116

Peyer's patches

Small intestin lamina propria and submucosa. M cells take up antigen. B cells stimulate germinal centers and IgA-secreting plasma cells are created. IgA receives protective secretory component and is then transported across epithelium to gut to deal with antigen.

117

nocturnal couph and dyspnea

GERD or Barrett's

118

Diffuse esophageal spasm (DES)

esophageal motility disorder presenting with severe non-cardiac chest pain due to uncoordinated contractions of esophageal body, mimics angina

119

Symptoms of whipple's disease

cardiac, arthralgias, and neurological

120

Celiac sprue antibodies and genetic association

HLA-B8, occurs primarily in jejunum, Anti-gliadin, anti-endomyseal, anti-reticulin,anti-transglutaminase

121

Acute gastritis etiology

decreased protection of mucosa, dt stress, NSAIDS, alcohol, uremia, burns (curling), head trauma (cushings),

122

Menetrier's disease

gastric hypertrophy with protein loss, parietal cell atrophy, and increased mucous cells. Precancerous. Rugae of stomach look like brain gyri

123

Virchow's node

supraclavicular node on left side (drains lower GI) and is a place of mets from stomach

124

Sister Mary Joseph's nodule

Perimbilical gastric metastasis

125

Familial adenomatous Polyposis (FAP)

AD; APC gene on chromosome 5q. Thousands of polyps.

126

Gardner's syndrome

FAP + osseous tumors and retinal hyperplasia with other soft tissue

127

Turcot's syndrome

FAP + CNS tumors

128

HNPCC

MSH2 gene mutaiton in DNA mismatch repair. Proximal colon is most common location (R-sided)

129

Carcinoid and B3 deficiency

Makes Serotonin which is synthsized by tryptophan so it can cause a secondary tryptophan deficiency leading to niacin deficiency

130

Alcoholic hepatitis

destruction via acetaldehyde which stimulates cells that used to store vitamin A to change and make collagen and fibrous tissue instead. There is a neutrophilic infiltration. Formation of mallory bodies which are ubiquinated keratin microfilaments.

131

Hepatocellular carcinoma risk factors

HBV HCV, alcohol, wilson's disease, hemachromatosis, alpha-1-AT, carcinogens, Aspergillus toxins.

132

Cavernous hemangioma

biopsy contraindicated due to risk of bleeding. Congenital malformations that enlarge by ectasia not hyperplasia. Common benign liver tumor; typically occurs at age 40.

133

primary sclerosing cholangitis

associated with ulcerative colitis. Etiology unknown. It looks like a beaded structure with onion skin lesions. Mostly occurs in men, pANCA, risk for cholangiocarcinoma. Hyper IgM.

134

Primary biliary sclerosis

autoimmune disease, histologically is granulomatous inflammation of INTRAhepatic bile ducts. Starts off variably throughout liver progresses to a diffuse green stained liver that is uniformly micronodular. + anti-mitochondrial antibodies. Associated with other autoimmune diseases especially women