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Flashcards in GI Deck (444):
1

ursodiol MOA

Nontoxic bile acid. Increases bile secretion + decreases cholesterol secretion and absorption.

2

ursodiol clinical use

PBC + gallstone prevention or dissolution.

3

Orlistat MOA

inhibits gastric and pancreatic lipase, thus leading to decreased breakdown and absorption of dietary fats.

4

Orlistat AE's

steatorrhea + decreased absorption of fat-soluble vitamins.

5

metoclopramide MOA

D2 receptor antagonist. Increases resting tone, contractility, LES tone, motility. Does not influence colon transport time.

6

metoclopramide clinical use

diabetic and postsurgery gastroparesis, antiemetic

7

metoclopramide contraindications

digoxin + diabetic agents + SBO or Parkinson disease (due to D2 receptor blockade)

8

metoclopramide AE's

parkinsonian effects, tardive dyskinesia, restlessness, drowsiness, fatigue, depression, diarhea.

9

ondansetron MOA

serotonin antagonist + decreases vagal stimulation

10

ondansetron AE's

headache + constipation + QT interval prolongation

11

Loperamide MOA

agonist at mu-opioid receptors; slows gut motility. Poor CNS penetration (low addictive potential)

12

loperamide AE's

constipation + nausea

13

Sulfasalazine -- MOA, clinical use, SE's

Sally Westcott in a sulfur geiser/sulfasalazine. Pyramid with sulfur geiser on top on right + tree with bark and hailing on it/MOA = combination of sulfapyridine (antibacterial) + 5-aminosalicylic acid (anti-inflammatory). Bacteria on counter throwing lasso around her/activated by colonic bacteria. Rachel in wheelchair next to counter/can cause drug-induced lupus. Riding a dead sperm/toxicity = malaise + nausea + sulfonamide toxicity + reversible oligospermia. /clinical use = UC + Crohn disease.

14

lactulose

osmotic laxative

15

osmotic laxatives AE's

diarrhea, dehydration.

16

octreotide MOA

long-acting somatostatin analog; inhibits secretion of various splanchnic vasodilatory hormones.

17

Octreotide AE's

nausea, cramps, steatorrhea + increased rick of cholethiasis due to CCK inhibition.

18

misoprostol MOA

PGE1 analog. increased production and secretion of gastric mucous barrier, decreases acid production.

19

misoprostol mechanism as abortifacent

Ripens cervix

20

Other use of misoprostol.

Maintains PDA.

21

misoprostol AE's

diarrhea

22

bismuth, sucralfate MOA

binds to ulcer base, providing physical protection and allowing HCO3- secretion to reestablish pH gradient in the mucous layer.

23

another use for bismuth, sucralfate

travelers' diarrhea.

24

shared AE of all antacids

hypokalemia

25

aluminum hydroxide AE's

constipation + hypophosphatemia + proximal muscle weakness + osteodystrophy + seizures

26

calcium carbonate AE's

hypercalcemia (milk-alkali syndrome) + rebound acid production

27

magnesium hydroxide AE's

Harvey milk (sean penn) from movie milk in middle of room giving magnus who’s benchpressing a blowjob: he’s shitting on a towel + IV pole next to him + is being shocked + riding a mini motorcycle/SE’s = diarrhea + hyporeflexia + hypotension + cardiac arrest.

28

What is a proton pump?

H+/K+ ATPase in stomach parietal cells.

29

ZES treatment

PPI

30

PPI AE's

Nate is banging Heidi on the table + magnus strong man on the table + carson with his ski gear at other end of table/SE’s = increased risk of C. diff infection + decreased serum Mg2+ with long-term use + atrophic gastritis + carcinoid tumors + headaches + GI disturbances. Rest of seats filled with skeletons/associated with osteoporosis and osteoporotic hip fractures (decreases calcium absorption;calcium carbonate requires an acidic environment for proper absorption).

31

H2 blocker MOA

reversible block of histamine H2 receptors --> decreased H+ secretion by parietal cells.

32

H2 Blocker AE's

- Cimetidine is the primary concern. Others are relatively free of these effects.
- CYP450 inhibitor + antiandrogen effects + can cross BBB (confusion, dizziness, headaches) and placenta + decreases renal excretion of creatinine.

33

ranitidine AE

Decreases renal excretion of creatinine.

34

Foregut region

pharynx t oduodenum

35

midgut region

duodenum to proximal 2/3 of transverse colon.

36

hindgut region

distal 1/3 of transverse colon to anal canal above pectinate line.

37

Midgut development

6th week--physiologic midgut herniates through umbilical ring.
10th week--returns to abdominal cavity + rotates around SMA, total 270 counterclockwise.

38

Defect in rostral fold closure

Sternal defects

39

Defect in lateral fold closure

Omphalocele, gastroschisis

40

defect in caudal fold closure leads to...

bladder exstrophy

41

gastroschisis

extrusion of abdominal contents through abdominal folds (typically right of umbilicus); not covered by peritoneum.

42

Most common tracheoesophageal anomalies

esophageal atresia with distal tracheoesophageal fistula (85%)

43

why does cyanosis occur with esophageal atresia?

Secondary to laryngospasm (to avoid reflux-related aspiration).

44

H-type esophageal atresia

Pure TEF. see FA

45

jejunal and ileal atresia pathophys

disruption of mesenteric vessels --> ischemic necrosis --> segmental resoprtion.

46

characteristic sign of jejunal and ileal atresia.

Bowel discontinuity or "apple peel."

47

epidemiology of hypertrophic pyloric stenosis

Most common cause of gastric outlet obstruction (1:600).

48

hypertrophic pyloric stenosis RF

Exposure to macrolides.

49

hypertrophic pyloric stenosis acid/base disturbance

hypokalemic hypochloremic metabolic alkalosis (vomiting of gastric acid and subsequent volume contraction).

50

pancreas embryology

Derived from foregut. Ventral pancreatic buds contribute to uncinate process and main pancreatic duct. Dorsal pancreatic bud alone becomes body, tail, isthmus, and accessory pancreatic duct. Both ventral and dorsal buds contribut to pancreatic head.

51

annular pancreas

ventral pancreatic bud abnormally encircles 2nd part of duodenum; forming ring of pancreatic tissue that may cause dudoenal narrowing and *nonbilious vomiting.

52

Pancreas divisum and timeframe

Ventral and dorsal parts fail to fuse at 8 weeks. Common and mostly asymptomatic, but may cause chronic abdominal pain and/or pancreatitis.

53

pancreas anatomy

codebook

54

SADPUCKER notes

Aorta AND IVC
2nd-4th parts of duodenum
Pancreas (except tail)
Esophagus (thoracic portion)

55

falciform connects

Liver to anterior abdominal wall

56

falciform contains

ligamentum teres hepatis

57

ligamentum teres hepatis derived from...

fetal umbilical vein

58

falciform derivative of...

ventral mesentery

59

hepatoduodenal connects...

liver to duodenum

60

hepatoduodenal

portal triad

61

pringle maneuver

Compressing hepatoduodenal ligament between thumb and index finger in omental foramen to control bleeding.

62

hepatoduodenal borders the...

omental foramen

63

omental foramen connnects

The greater and lesser sacs.

64

gastrohepatic connects

liver to lesser curvature of stomach

65

gastrohepatic contains

- gastric arteries
- separates greater and lesser sacs on the right.

66

what do you need to cut to access the lesser sac?

gastrohepatic ligament

67

gastrocolic connects... forms..

-greater curvature and transverse colon.
- part of greater omentum.

68

gastrocolic contains

gastroepiploic arteries

69

What separates greater and lesser sacs on the left?

gastrosplenic

70

gastrosplenic connects...forms...

- greater curvature and spleen
- part of greater omentum

71

gastrosplenic contains

short gastrics, left gastroepiploic

72

splenorenal connects....

Spleen to posterior abdominal wall.

73

Splenorenal contains

splenic artery and vein + tail of pancreas

74

Layers of gut wall

inside to outside -- MSMS
Mucosa
Submucosa
Muscularis externa
Serosa

75

Mucosa contains...

epithelium, lamina propria, muscularis mucosa.

76

submucosa includes...function..

- Submucosal nerve plexus (Meissner).
- Secretes fluid.

77

Muscularis externa includes...

Myenteric nerve plexus (Auerbach)

78

serosa caveat

Called serosa when intraperitoneal, adventitia when retroperitoneal.

79

erosions vs. ulcers

Ulcers can extend into submucosa, inner or outer muscular layer. Erosions are confined to mucosa.

80

Stomach basal rhythm

3 waves/min

81

Duodenum basal rhythm

12 waves/min

82

Ileum basal rhythm

8-9 waves/min

83

Muscularis composition

Inner circular layer, myenteric nerve plexus (Auerbach), outer longitudinal layer

84

Brunner glands

HCO3- secreting cells of submucosa.

85

Duodenum contains

Brunner glands + cytps of Lieberkuhn + villi and microvilli

86

histology of jejunum

Plicae circularis and crypts of Lieberkuhn.

87

Peyer patches

Lymphoid aggregates in lamina propria, submucosa.

88

Where are peyer patches?

Ileum

89

Ileum histology

peyer patches + plicae circulares + crypts of lieberkuhn.

90

Where are the largest number of goblet cells in the small intestine?

Ileum

91

Colon histology

Crypts of Lieberkuhn but no villi; abundant goblet cells.

92

abdominal aorta branches rule

Arteries supplying GI structures branch anteriorly. Arteries supplying non-GI structures branch laterally and posteriorly.

93

Middle suprarenal anatomic location.

T12

94

celiac trunk anatomic location.

T12

95

Fist lumbar anatomic location

L1

96

Renal anatomic location

L1

97

SMA anatomic location

L1

98

Gonadal anatomic location

Just above L2

99

IMA anatomic location

L3

100

Bifurcation of abdominal anatomic location

L4 (biFOURcation)

101

Common iliacs anatomic location

L5

102

SMA artery syndrome
1) presentation
2) anatomy
3) scenario

1) Intermittent intestinal obstruction symptoms (primarily postprandial pain)
2) Transverse (3rd) portion of duodenum is compressed between SMA and aorta.
3) Conditions associated with diminished mesenteric fat (eg, low body weight/malnutrition).

103

Foregut
1) arterial supply
2) PS innervation
3) vertebral level
4) structures supplied

1) Celiac
2) Vagus
3) T12/L1
4) Pharynx (vagus nerve only) and lower esophagus (celiac artery only) to proximal duodenum; liver, gallbladder, pancreas, spleen (mesoderm)

104

Midgut
1) arterial supply
2) PS innervation
3) vertebral level
4) structures supplied

1) SMA
2) vagus
3) L1
4) distal duodenum to proximal 2/3 of transverse colon

105

Hindgut
1) arterial supply
2) PS innervation
3) vertebral level
4) structures supplied

1) IMA
2) Pelvic
3) L3
4) distal 1/3 transverse colon to upper portion of rectum.

106

TIPS procedure

Transjugular intrahepatic portosystemic shunt (TIPS). Creates a shunt between portal vein and hepatic vein, thus relieving portal HTN by shunting blood to the systemic circulation, bypassing the liver.

107

Varices seen with portal hypertension

(gut, butt, and caput (medusa) --> esophageal, rectal (anorectal varices), caput medusa

108

portosystemic rectal anastomosis

superior rectal with middle and inferior rectal.

109

caput medusae anastomosis

Paraumbilical with small epigastric veins of the anterior abdominal wall.

110

esophageal varices anastomosis

left gastric with azygos

111

pectinate (dentate) line

Formed where endoderm (hindgut) meets ectoderm.

112

Venous drainage above pecinate line

Superior rectal vein --> ifnerior mesenteric --> portal system

113

lymphatic drainage above pectinate line

internal iliac lymph nodes

114

venous drainage below pectinate line

inferior rectal vein --> internal pudendal vein --> internal iliac vein --> common iliac vein --> IVC

115

lymphatic drainage below pectinate line

Superficial inguinal nodes.

116

Anal fissure RF's

low fiber diet + constipation.

117

Kupffer cells

Specialized macrophages that form the lining of sinusoids

118

Hepatic stellate (Ito) cells 1) location 2) function

1) space of Disse
2) store vitamin A (when quiescent), produce ECM when activated.

119

intermediate zone, pericentral vein (centrilobular) zone, intermediate zone

Zone 1 = periportal zone
Zone 2 = intermediate zone
Zone 3 = pericentral vein (centrilobular) zone

120

Site of alcoholic hepatitis

Zone III

121

yellow fever affects...

zone II

122

ingested toxins (eg cocaine) affect....

Zone I

123

zone affected 1st by ischemia

Zone III (farthest from arterial supply)

124

zone affected 1st by viral hepatitis

Zone I

125

ampulla of vater and 2) clinical significance

1) little widened space behind sphincter of oddi in head of pancreas (FA 347)
2) gallstones that lodge here an block both the common bile and pancreatic ducts causing "double duct sign" --> both cholangitis and pancreatitis.

126

cystic duct

Duct that drains gallbladder

127

painless juandice

pancreatic adenocarcinoma (usually ductal) in head of pancreas that causes of obstruction of common bile duct.

128

femoral region organization

NAVeL --> nerve, artery, vein, lymphatics

129

femoral triangle

contains femoral nerve, artery, vein

130

femoral sheath

fascial tube 3-4 cm below inguinal ligament. Contains femoral vein, artery, and canal (deep inguinal lymph nodes) but NOT femoral nerve.

131

femoral triangle borders

- superiorly by inguinal ligament.
- medially by medial border of adductor longus.
- laterally by medial border of sartorius muscle.

132

superficial inguinal ring

External obie standing in the middle of a golden ring/formed by opening in the external oblique muscle aponeurosis.

133

Deep inguinal ring

• Code: hole down to china beneath trannies/opening in the transversalis fascia.

134

Layers of inguinal canal

Obie Spear on outside, closer to bank with stomach covered in big sperm/external spermatic fascia derived from external oblique. Obie hanging from inside pulling testicles up with a rope/cremasteric muscle and fascia derived from internal oblique. Line of trannies with sperm that have buried into their stomachs/internal spermatic fascia derived from transversalis fascia.

135

Site of protrusion of direct hernia

abdominal wall

136

Site of protrusion of indirect hernia

deep inguinal ring

137

conjoined tendon

formed by transversus abdominis muscle + internal oblique muscle

138

umbilical hernia defect location

defect at linea alba

139

incarceration

hernia that can't be reduced.

140

strangulation

hernia that becomes ischemic and necrotic

141

presentation of complicated hernias

tenderness, erythema, fever.

142

structure defective in congenital diaphragmatic hernia and usual location

- pleuroperitoneal membrane.
- left side (no liver for protection)

143

Site of protrusion of direct inguinal hernia

Hesselbach triangle. Bulges directly through abdominal wall.

144

Other details of direct inguinal hernia

- goes through external (superficial) inguinal ring only.
- covered by external spermatic fascia.
- usually in older men.

145

Femoral hernia epidemiology

usually females.

146

femoral hernia protrusion

Below inguinal ligament through femoral canal below and lateral to pubic tubercle.

147

caveat about femoral hernias

More likely to incarcerate or strangulate.

148

Inguinal (hesselbach) triangle

Inferior epigastric vessels, lateral border of rectus abdominis, inguinal ligament

149

Gastrin source and location

G cells (****antrum of stomach, duodenum)

150

gastrin action

increases gastric H+ secretion, growth of gastric mucosa, gastric motility.

151

gastrin 1) increased by 2) decreased by

1) stomach distention/alkalinization, amino acids, peptides, vagal stimulation via gastrin-releasing peptide (GRP)
2) ph

152

what increases gastrin production?

chronic PPI use, chronic atrophic gastritis (H pylori), ZES

153

Somatostatin source

D cells (pancreatic islets, Gi mucosa)

154

somatostain actions

decreases gastric acid and pepsinogen secretion + pancreatic and small intestine fluid secretion + gallbladder contraction + insulin and glucagon release

155

somatostain regulation

increased by acid, decreased by vagal stimulation.

156

CCK source

I cells (duodenum, jejunum)

157

CCK action

Increases pancreatic secretion + gallbladder contraction. Decreases gastric emptying. Increases sphincter of oddi relxation.

158

CCK regulation

Increased by fatty acids, amino acids.

159

How does CCK cause pancreatic secretion

Acts on neural muscarinic pathways.

160

Secretin source

S cells (duodenum)

161

Secretin actions

Increases pancreatic HCO3- secretion + bile secretion. Decreases gastric acid secretion. Functions to neutralize gastric acid in duodenum, allowing pancreatic enzymes to function.

162

Secretin regulation

Increased by acid, fatty acids in lumen of duodenum.

163

glucose-dependent insulinotropic peptide

another name for GIP.

164

GIP source

K cells (duodenum, jejunum)

165

GIP functions

Exocrine: decreases gastric H+ secretion.
Endocrine: increases insulin release.

166

GIP regulation

Increased by fatty acids, amino acids, oral glucose.

167

Why does oral glucose lead to increased insulin compared to IV

GIP secretion.

168

drug that that acts as a motilin receptor agonist

erythromycin

169

VIP source

PS ganglia in sphincters, gallbladder, small intestine

170

VIP functions

Increases intestinal water and electrolyte secretion + increases relaxation of intestinal smooth muscle and sphincters.

171

VIP regulation

Increased by distention and vagal stimulation, decreased by adrenergic input.

172

Why is there increased LEs tone in achalasia?

Loss of NO secretion.

173

Ghrelin source

stomach

174

Ghrelin clinical relevance

Increased in Prader-Willi, decreased after gastric bypass surgery.

175

gastric acid positive regulators

histamine, ACh, gastrin

176

gastric acid negative regulation

somatostatin, GIP, prostaglandin, secretin.

177

pepsin source and function

chief cells, protein digestion

178

Pepsin regulation

increased by vagal stimulation, local acid

179

Bicarbonate source

mucosal cells (stomach, duodenum, salivary glands, pancreas)
brunner glands (duodenum)

180

where does bicarbonate sit?

Trapped in mucus that covers the gastric epithelium.

181

How does gastrin increase gastric acid secretion?

Indirectly through enterochromaffin-like cells (ECL cells) leading to histamine release rather than through its direct effect on parietal cells.

182

Pancreatic secretions tonicity + flow variance

1) isotonic
2) low flow --> high Cl-
high flow --> high HCO3-

183

alpha-amylase caveat

secreted in active form. Doesn't need to be activated.

184

name some proteases

trypsin, chymotrypsin, elastase, carboxypeptidase.

185

How is trypsinogen converted to trypsin?

Enterokinase/enteropeptidase, a brush-border enzyme on duodenal and jejunal mucosa.

186

Glucose and galactose absorption

Taken up by SGLTI (Na+ dependent).

187

Fructose absorption

Facilitated diffusion by GLUT-5.

188

GLUT 2 function

transports all monosaccharides (glucose, galactose, and fructose) to blood.

189

Functon of D-xylose absorption test

Distinguishes GI mucosal damage from other causes of malabsorption.

190

B12 absorption caveat

absorbed with bile salts.

191

peyer patch and location

unencapsulated lymphoid tissue found in lamina propria and submucosa of ileum.

192

Where do IgA-secreting plasma cells sit? What are they derived from

Lamina propria. Derived from B cells when stimulated in germinal centers.

193

Composition of bile salts

Bile acids conjugated to glycine or taurine, making them water soluble.

194

Composition of bile

Bile salts + phospholipids + cholesterol + bilirubin + water + ions.

195

Enzyme catalyzing rate-limiting step of bile acid synthesis.

Cholesterol 7alpha-hydroxylase.

196

Bile functions

1) Digestion and absorption of lipids and fat-soluble vitamins.
2) Cholesterol excretion (body's only means of eliminating cholesterol)
3) Antimicrobial activity (via membrane disruption).

197

Bilirubin cycle

Heme is metabolized by heme oxygenase to biliverdin --> biliverdin reduced to bilirubin --> unconjugated bilirubin is removed from blood by liver, conjugated with glucuronate, and excreted in bile --> gut bacteria metabolize conjugated bilirubin to urobilinogen --> 80% of urobilinogen is excreted in feces as sercobilin (brown color of stool). 20% of urobilinogen remains in gut. Of that 20%, 10% goes to kidney and is excreted in urine as urobilin (giving urine yellow color) and 90% goes back through enterohepatic circulation to the liver.

198

Direct bilirubin

conjugated with glucuronic acid; water soluble.

199

Indirect bilirubin

Unconjugated; water insoluble.

200

Where does initial part of bilirubin cycle occur?

RBCS --> heme --> unconjugated bilirubin occurs in macrophages.

201

enzymes that conjugates bilirubin

UDP-glucuronosyl-transfease.

202

Benign/malignant pattern of salivary gland tumors.

Most commonly benign and in parotid gland. Tumors in smaller glands more likely malignant.

203

Typical presentation of salivary gland tumor

Painless mass/swelling.

204

What does facial pain or paralysis in a salivary gland mass suggest?

Malignant involvement of CN VII.

205

Most common salivary gland tumor

Pleomorphic adenoma

206

Pleomorphic adenoma characteristics and composition

Benign mixed tumor. Composed of chondromyxoid stroma and epithelium and recurs if incompletely excised or ruptured intraoperatively.

207

Most common malignant salivary gland tumor

mucoepidermoid carcinoma.

208

Another name for Warthin tumor

Papillary cystadenoma lymphomatosum.

209

Warthin tumor

Benign cystic tumor with germinal centers.

210

Causes of secondary achalasia

1) chagas disease 2) extraesophageal malignancies (mass effect or paraneoplastic)

211

Barium swallow finding of achalasia

birds break

212

achalasia characteristics

Failure of relaxation of LES due to loss of myenteric (Auerbach) plexus. High LES resting pressure and uncoordinated or absent peristalsis, leading to progressive dysphagia to solids and liquids.

213

Obstructive dysphagia presentation vs. achalasia

Obstructive dysphagia only occurs with solids, achalasia occurs with both liquids and solids.

214

Endoscopy findings in eosinophilic esophagitis

Esophageal rings and linear furrows.

215

patient presenting with GERD but unresponsive to GERD therapy consider...

eosinophilic esophagitis

216

Pathophys of food impaction in eosinophilic esophagitis

Food allergens --> dysphagia --> food impaction.

217

What causes esophageal strictures?

1) Caustic ingestion
2) Acid reflux

218

esophageal varices

dilated submucosal veins in lower 1/3 of esophagus secondary to portal HTN.

219

atypical but common presentation of GERD

cough + hoarseness (laryngopharyngeal reflux).

220

GERD association

asthma

221

Plummer-Vinson triad

dysphagia + iron deficiency anemia + esophageal webs

222

plummer vinson association

Glossitis

223

sclerodermal esophageal dystomility pathophys

esophageal smooth muscle atrophy --> decreased LES pressure and dysmotility --> acid reflux and dysphagia --> stricture, Barrett esophagus, and aspiration.

224

Barrett's cancer association

ADENOCARCINOMA

225

more common esophageal cancer worldwide

squamous cell carcinoma

226

RF's for esophageal adenocarcinoma

Chronic GERD, barrett's, obesity, smoking, achalasia

227

part of esophagus affected in squamous vs. adeno

Upper 2/3 = SCC
Lower 1/3 = adeno

228

prostaglandin affected by NSAIDs

PGE2

229

Curling ulcers

Complications from severe burns. (burned by the curling iron)

230

Curling ulcer pathophys

hypovolemia --> mucosal ischemia.

231

Cushing ulcer

Ulcer resulting from brain injury (cushin the brain)

232

Cushing ulcer pathophys

Brain injury --> increased vagal stimulation --> increased ACh --> increased H+ production.

233

Chronic gastritis pathophys

Mucosal inflammation, leads to atrophy (hypochlorhydria --> hypergastrinemia) and intestinal metaplasia.

234

H pylori cancer association

MALT lymphoma

235

H pylori location

affects antrum first, then spreads to body of stomach.

236

autoimmune gastritis location of damage

body/fundus of stomach

237

menetrier benign/malignant?

precancerous

238

gastric cancer epidemiology

Gastric adenocarcinoma --> lymphoma --> GI stromal tumor --> carcinoid (rare).

239

Gastric cancer personality + presentation

Early aggressive local spread with node/liver metastases. Often presents late with weight loss + early satiety, acanthosis nigricans, leser-trelat.

240

Intestinal gastric cancer associations

H pylori, dietary nitrosamines (smoked foods), tobacco smoking, achlorhydria, chronic gastritis.

241

Intestinal gastric cancer location + what it looks like

Lesser curvature; looks like ulcer with raised margins.

242

Diffuse gastric cancer associations

NOT associated with H pylori. Signet ring cells; stomach wall grossly thickened and leathery (linitis plastica)

243

Krukenberg tumor histology

Abundnat mucin-secreting, signet ring cells.

244

Gastric ulcer pain vs. duodenal ulcer pain

Gastric, Greater with meals. Duodenal decreases with meals.

245

H pylori association with gastric or duodenal ulcers

Causes pretty much all duodenal ulcers and 70% of gastric ulcers.

246

Gastric ulcer management

Biopsy margins to rule out malignancy

247

Gastric ulcer benign/malignant?

Increased risk of carcinoma

248

Gastric ulcer mechanism

decreased mucosal protection against gastric acid.

249

Duodenal ulcer mechanism

decreased mucosal protection OR increased gastric acdi secretion

250

Other causes of duodenal ulcrs

ZES

251

duodenal ulcer -- benign/malignant?

Usually benign.

252

Duodenal ulcer association

hypertrophy of brunner glands

253

duodenal area prone to hemorrhaging

posterior more common than anterior.

254

Most common complication of ulcers

hemorrhaging

255

Artery associated with ruptured gastric ulcer on lesser curvature of stomach

left gastric

256

Artery associated with hemorrhaging ulcer on posterior wall of duodenum

gastroduodenal

257

Potential ulcer complications

1) hemorrhaging
2) obstruction (pyloric channel, duodenal)
3) perforation.

258

Area of duodenum prone to perforation.

anterior>posterior.

259

Free air under diaphragm with referred pain to shoulder via phrenic nerve....

perforated duodenum from duodenal ulcers.

260

cancer and celiac's?

moderately increased risk of T-cell lymphoma

261

histo findings in celiac's

villous atrophy + crypt hyperplasia + **intraepithelial lymphocytosis.

262

area primarily affected by celiac's

mucosal absorption decreased in distal duodenum and/or proximal jejunum.

263

Test for celiacs

1) serology for antibodies
2) d-xylose for malabsorption

264

d-xylose results

1) if blood and urine levels are decreased --> mucosal defect or bacterial overgrowth
2) if pancreatic insufficiency, then will be normal.

265

Material that accumulates in clear cell carcinoma

high in glycogen and lipids

266

lactose intolerance diagnosis + analyzing results

lactose hydrogen breath test. Positive for lactose malabsorption if postlactose breath hydrogen value rises > 20 ppm compared with baseline.

267

Thing to remember about pancreatic insufficiency

not only malabsorption of fat-soluble vitamins but also B12

268

Pancreatic insufficiency diagnosis

Decreased duodenal pH (bicarbonate) and fecal elastase.

269

region of intestine affected in tropical sprue

Duodenum + jejunum but can involve ileum.

270

anemia relationship to tropical sprue

due to folate deficiency, and, later, B12 deficiency.

271

ulcers in chrohn's

linear ulcers

272

microscopic morphology in crohn's

noncaseating granulomas + lymphoid aggregates.

273

Other complications of Crohn's

1) enterovesical fistula, which can cause recurrent UTI and pneumaturia.
2) phlegmon/abscess
3) strictures (causing obstruction)
4) perianal disease.
5) kidney stones
6) gallstones

274

antibiotics for Crohn's patients

Ciprofloxacin + metronidazole

275

UC gross morphology

1) Mucosal and submucosal inflammation only.
2) Friable mucosal pseudopolyps with freely hanging mesentery.
3) Loss of haustra --> "lead pipe" appearance on imaging

276

Complications of UC

1) Fulminant colitis
2) Toxic megacolon
3) Perforation

277

Primary sclerosing cholangitis lab finding

p-ANCA

278

UC treatment

5-aminosalicylic preparations (eg, mesalamine), 6-mercaptopurine, infliximab, colectomy.

279

IBS presentatoin

Recurrent abdominal pain associated with 2 of following
1) pain improves with defecation
2) change in stool frequency
3) change in appearance of stool.
-- can be diarrhea-predominant or constipation-predominant or mixed.

280

appendicitis pathophys

In adults --> obstruction by fecalith.
In kids --> lymphoid hyperplasia.

281

Test for appendicitis and location

- McBurney point
- 1/3 the distance from right anterior superior iliac spine to umbilicus.

282

Other signs in appendicits

Psoas, obturator, Rovsing signs. guarding and rebound tenderness on exam.

283

appendicitis differential

diverticulitis (elderly), ectopic, yersinia

284

Most common site of diverticulum

Sigmoid colon

285

What does "false" mean in relation to diverticulum?

Attenuated muscularis externa. Only mucosa and submucosa outpouch.

286

True diverticulum

all 3 gut wall layers, Meckels

287

Area prone to false diverticula

Where vasa recta perforate muscularis externa.

288

diverticulosis

Many false diverticula of the colon, commonly sigmoid.

289

epidemiology of diverticulosis

1/2 of people over age 60.

290

diverticulosis pathophys

Increased intraluminal pressure and focal weakness in colonic wall. Low-fiber diets.

291

Painless bleeding in a person with diverticulosis

Painless hematochezia. *not necessarily diverticulitis.

292

diverticulitis

Diverticulosis with inflamed microperforations.

293

Presentation of diverticulitis

LLQ pain + fever + leukocytosis.

294

Diverticulitis treatment

antibiotics

295

Complications of diverticulitis

1) abscess
2) fistula (colovesical fistula leading to pneumaturia)
3) obstruction (inflammatory stenosis)
4) perforation (leading to peritonitis)

296

If diverticulitis is complicated, management is...

Percutaneous drainage or surgery.

297

Where does mucosal tissue herniate in Zenker's?

Killian triangle between thyropharyngeal and cricopharyngeal parts of the inferior pharyngeal constrictor.

298

Meckel presentation

melena + RLQ pain.

299

Meckel complications

intussusception + volvulus + obstruction near terminal ileum.

300

omphalomesenteric cyst

Cystic dilation of vitelline duct. Not peristence of vitelline duct.

301

Six 2's of Meckel's

2x as likely in males
2 inches long
2 feet from ileocecal valve
2% of population
presents in first 2 years of life
2 types of epithelia (gastric/pancreatic).

302

Hirschsprung etiology

Congenital megacolon characterized by lack of ganglion cells/enteric nervous plexuses (Auerbach and Meissner plexuses) in distal segment of colon.

303

Hirschprung genetic association

mutations in RET

304

Hirschsprung presentation

Bilious emesis + abdominal distention + failure to pass meconium within 48 hours --> chronic constipation.

305

Hirschsprung diagnosis

Rectal suction biopsy

306

Hirschsprung treatment

Resection

307

Positioning of bowel in malrotation

small intestine in ball in bottom right, large intestine on left side, ladd band between large intestine and liver.

308

Complications of malrotation

1) volvulus
2) duodenal obstruction

309

intussusception

PROXIMAL segment telescopes into distal segment.

310

viral infection and intussusception etiology

adenovirus --> peyer patch hypertrophy --> lead point.

311

Most common pathologic lead point

Meckel diverticulum.

312

Usual location of acute mesenteric ischemia

Embolic occlusion of SMA.

313

chronic mesenteric ischemia pathophys

"intestinal angina": atherosclerosis of celiac, IMA, or SMA --> intestinal hypoperfusion --> postprandial epigastric pain --> food aversion and weight loss.

314

colonic ischemia presentation

crampy abdominal pain followed by hematochezia.

315

Watershed areas

splenic flexure, distal colon.

316

Most common locations of angiodysplasia

Cecum, terminal ileum, ascending colon.

317

Most common cause of SBO

adhesions

318

Adhesion presentation

Fibrous band of scar tissue. Can have well-demarcated necrotic zones.

319

Ileus

Intestinal hypomotility without obstruction --> constipation and decreased flatus; distended/tympanic abdomen with decreased bowel sounds.

320

Ileus causes

abdominal surgeries, opiates, hypokalemia, sepsis.

321

ileus treatment

Bowel rest, electrolyte correction, cholinergic drugs (stimulate intestinal motility).

322

necrotizing enterocolitis pathophys

formula fed premies --> immature immune system --> necrosis of intestinal mucosa (primarily colonic) with possible perforation, which can lead to pneumatosis intestinalis, free air in abdomen, portal venous gas.

323

What induces COX-2 production?

IL-2

324

Inguinal (hesselbach) triangle borders

Inferior epigastric vessels, lateral border of rectus. abdominis, inguinal ligament

325

hyperplastic polyp location and presentation

non-neoplastic and smaller. Rectosigmoid area.

326

hamartomatous polyps histology

growths of normal colonic tissue with distorted architecture.

327

adenomatous polyps + presentation

neoplastic, via chromosomal instability pathway. APC and KRAS mutations.
Usually asymptomatic; may present with occult bleeding.

328

serrated polyps
1) genetics
2) epidemiology

1) premalignant via CPG hypermethylation phenotype pathway with microsatelite instability and mutations in BRAF.
2) Up to 20% of cases of sporadic CRC.

329

2 hit hypothesis

You need to lose 2 tumor suppressor genes before getting cancer.

330

Gardner syndrome

FAP + osseus and soft tissue tumors + congenital hypertrophy of retinal pigment epithelium + impacted/supernumerary teeth.

331

Peutz Jeghers syndrome

o Coded character: Megan Yeiter. Emerging from jegher bag in basement with hyperpigmented mouth, lips, genitalia and covered in ham/syndrome featuring numerous hamartomas throughout GI tract. /presentation = hyperpigmented mouth/lips/hands/genitalia + bloody stool (due to intestinal hamartomas). Kenny sitting to her left + Mr. Kolkhorst sitting on a toilet behind her + tammy on her right + T with gut next to kenny/associated with increased risk of colorectal, breast, stomach, small bowel, and pancreatic cancers (but hamartomas themselves don’t undergo malignant transformation) + ovary/uterus/cervix/lung. Femdom chick whipping her from right /autosomal dominant. /pedunculated polyps. Intussuscepted bowel hanging over her from left/hamartomas can occasionally serve as the lead point for intussusception.

332

Peutz jeghers mutation

STK11/LKB1 gene.

333

Juvenile polyposis syndrome
1) presentation
2) prognosis

- AD syndrome in children less than 5 featuring numerous hamartomatous polyps in colon, stomach, small bowel.
- increased risk of CRC

334

Epidemiology of cancer progression in lynch syndrome + area of involvement

80% progress to CRC + proximal colon is always involved.

335

Cancers associated with Lynch syndrome

Associated with endometrial, ovarian, and skin cancers.

336

genetics of CRC

25% have a family history.

337

CRC RF's

1) adenomatous and serrated polyps
2) familial cancer syndromes
3) IBD
4) tobacco use
5) diet of processed meat with low fiber.

338

Areas most commonly involved in CRC

Rectosigmoid>ascending>descending

339

Ascending mass in CRC presentation

exophytic mass + IDA + weight loss

340

descending mass in CRC presentation

Infiltrating mass, partial obstruction, colicky pain, hematochezia.

341

Caveat about CEA tumor marker for CRC

Good for monitoring recurrence, shouldn't be used for screening.

342

Screening for CRC

Colonoscopy, flexible sigmoidoscopy, fecal occult blood test, or fecal DNA test.

343

Genetic cause of most sporadic CRC

Mutations in APC

344

Mismatch repair gene

MLH1

345

Chromosomal instability pathway for CRC

APC --> KRAS --> p53, DCC

346

Cells responsible for fibrosis in cirrhosis

Stellate cells

347

histology of fibrosis

diffuse bridging fibrosis + regenerative nodules.

348

Causes of portal HTN

cirrhosis + vascular obstruction (Budd-Chiari) + schisto

349

metabolic presentation of cirrhosis and portal HTN

cardiomyopathy + peripheral edema

350

hematologic presentation of cirrhosis and portal HTN

thrombocytopenia + anemia + coagulation disorders

351

fetor hepaticus

"breath of the dead." Late sign of liver failure and feature of hepatic encephalopathy. Breath has a sweet, fecal smell to it.

352

Reproductive presentation of cirrhosis and portal HTN

testicular atrophy + gynecomastia + amenorrhea

353

What does AST greater than ALT in nonalcoholic liver disease suggest...

progression to advanced fibrosis or cirrhosis.

354

ALT, AST pattern in most liver disease

ALT is greater than AST, alcoholic liver disease is the exception

355

Marker of cholestasis

ALP

356

gamma-glutamyl transpeptidase

increased in various liver and biliary disease, but not in bone disease.

357

Albumin as a marker of liver disease

decreased in advanced liver disease

358

Prothrombin as a marker of liver disease

Increased in advanced liver disease (decreased production of clotting factors)

359

Platelets as a marker of liver disease

decreased in advanced liver disease

360

Why are platelets decreased in advanced liver disease?

decreased thrombopoietin, liver sequestration and portal HTN (splenomegaly/splenic sequestration).

361

viral infections associated with Reye syndrome

VZV + influenza B

362

Reye syndrome pathophys

aspirin metabolites decrease beta-oxidation by reversible inhibition of mitochondrial enzymes.

363

alcoholic hepatitis histology

swollen and necrotic hepatocytes with neutrophilic infiltration.

364

Mallory bodies

intracytoplasmic eosinophilic inclusions of damaged keratin filaments.

365

alcoholic cirrhosis histology

Micornodular, irregularly shrunken liver with "hobnail" appearance. Sclerosis around central vein.

366

Non alcoholic fatty liver disease:

Super fat hippos sitting around perimeter + inflating balloons + grim reaper sitting in middle/metabolic syndrome (insulin resistance) fatty infiltration of hepatocytes “cellular ballooning” and eventual necrosis. Ollie sitting in chair holding fetus in front of grim reaper/may cause cirrhosis and HCC. /independent of alcohol use. Huge alan + tiny Trojan Spartan to his right/ALT>AST.

367

antibiotic treatment for hepatic encephalopathy

rifaximin or neomycin

368

hepatic encephalopathy trigers

1) increased NH3 production and absorption (due to dietary protein, GI bleed, constipation, infection).
2) decreased NH3 removal (due to renal failure, diuretics, bypassed hepatic blood flow post-TIPS).

369

lactulose MOA in hepatic encephalopathy

Decreases intraluminal ammonia absorption. Lactulose is metabolized by gut bacteria into lactic and acetic acid. The H+ ions emitted bind to NH3, converting it into NH4+ and thereby preventing it’s absorption. Thus, increase NH4+ generation.

370

alpha1-antitrypsin deficiency cancer association

HCC

371

cavernous hemangioma prognosis

benign

372

hepatic adenoma prognosis

May regress spontaneously or rupture (abdominal pain and shock

373

Most common liver tumor mets

GI + breast + lung

374

budd-chiari associations

hypercoagulable states + polycythemia vera + postpartum state + HCC

375

caveat aboud Budd-chiari

Absence of JVD.

376

pathophys of alpha1-antitrypsin deficiency in liver

Misfolded gene product protein aggregates in hepatocellular ER, causing cirrhosis with PAS positive globules in liver.

377

hyperbilirubinemia associated with primary sclerosing cholangitis

conjugated

378

hyperbilirubinemia associated with PBC

conjugated

379

Mixed (direct and indirect hyperbilirubinemia) seen in...

hepatitits, cirrhosis

380

physiologic neonatal jaundice prognosis

usually resolves without treatment in 1-2 weeks.

381

phototherapy for neonatal jaundice mechanize

Isomerizes unconjugated bilirubin to water-soluble form

382

hereditary hyperbilirubinemias genetics

all AR

383

Gilbert syndrome mechanism

Mildly decreased UDP-glucoronysltransferase conjugation and impaired bilirubin uptake.

384

Treatment for Crigler-Najjar type I

Plasmapheresis and phototherapy

385

Type II Crigler-Najjar

Less severe and responds to phenobarbital, which increases liver enzyme synthesis.

386

Rotor syndrome etiology

Impaired hepatic uptake and excretion.

387

another name for conjugated bilirubin

bilirubin diglucuronide

388

another name for Wilson's

hepatolenticular degeneration

389

gene mutation in Wilson's

ATP7B

390

labs in Wilson's

DECREASED ceruloplasmin

391

Kaysr-Fleischer rings

deposits in Descemet membrane of cornea

392

Wilson's treatment

chelation with penicillamine or trientine, oral zinc.

393

HFE chromosome

6

394

hemochromatosis
- ferritin
- TIBC
- transferrin

Increased ferritin, increased iron, decreased TIBC, increased transferrin saturation.

395

Iron overload also seen in..

chronic transfusion therapy (beta-thalassemia major)

396

hemochromatosis presentation

Presents after age 40 when total body iron > 20 g.

397

cardiac presentation of hemochromatosis

dilated cardiomyopathy (reversible)

398

hemochromatosis treatment

Repeated phlebotomy, chleation with deferasirox, deferoxamine, oral deferiprone.

399

cholestatic pattern of LFTs (characteristic of biliary tract disease)

Increased conjugated bilirubin, increased cholesterol, increased ALP.

400

Lab findings in PSC

- p-ANCA positive
- increased IgM

401

PSC complications

1) biliary cirhosis
2) increased risk of cholangiocarcinoma and gallbladder cancer.

402

Secondary biliary cirrhosis 1) pathophys

1)Extrahepatic biliary obstruction leads to increased pressure in intrahepatic ducts, leading to injury/fibrosis and bile stasis.

403

Secondary biliary cirrhosis epidemiology

Patients with known obstructive lesions (gallstones, biliary strictures, pancreatic carcinoma)

404

Secondary biliary cirrhosis complication

Ascending cholangitis

405

what causes gallstones

increased cholesterol and/or bilirubin, decreased bile salts, and stasis.

406

cholesterol gallstone associations

Obestity, crohns, advanced age, estrogen therapy, multiparity, rapid weight loss, Native American.

407

black pigment stone composition

Calcium bilirubinate

408

Brown pigment stone etiology

infection

409

pigment stone associations

Crohn's, advanced age, chronic hemolysis, alcoholic cirrhosis, biliary infections, total parenteral nutrition.

410

complications of gallstones

1) cholecystitis
2) acute pancreatitis
3) ascending cholangitis
4) fistula between gallbladder and GI tract (air in biliary tree0

411

charcot triad of cholangitis

Jaundice + fever + RUQ pain

412

pneumobilia

air in biliary tree

413

gallstone ileus

osbtruction of ileocecal valve due to gallstone from fistula

414

Increased ALP suggests

bile duct involvement (ascending cholangitis)

415

cholecystitis diagnosis

US or cholescintigraphy (HIDA, or hepatobiliary iminiodiacetic acid scan).

416

causes of alcalculous cholecystitis

ischemia and stasis or CMV

417

causes of acute pancreatitis

I GET SMASHED. Idiopathic, Gallstones, Ethanol, Trauma, Steroids, Mumps, Autoimmune disease, Scorpion sting, Hypercalcemia/Hypertriglyceridemia (>1000 mg/dL), ERCP, Drugs (sulfa drugs, NRTIs, protease inhibitors).

418

acute pancreatitis diagnosis

2/3 criteria: acute epigastric pain often radiating to the back, increased serum amylase or lipase (more specific) to 3x upper limit of normal, or characteristic imaging findings.

419

another complication of acute pancreatitis

hypocalcemia (precipitation of Ca2+ soaps)

420

chronic pancreatitis

Chronic inflammation, atrophy, calcification of the pancreas.

421

chronic pancreatitis caveat

amylase and lipase may or may not be elevated (almost always elevated in acute pancreatitis)

422

pancreatic adenocarcinoma personality

Often metastatic at presentation with average survival around 1 year.

423

Trousseau syndrome

migratory thrombophlebitis

424

Courvoisier sign

palpable, nontender gallbladder, characteristic of pancreatic adenocarcinoma.

425

Treatment for pancreatic adenocarcinoma

Whipple procedure + chemo + radiation.

426

gastrin pathway

Gq

427

somatostatin pathway

Gi

428

Prostaglandin pathway

Gi

429

alkaline tide

increased blood pH after gastric acid secretion (eg, after meals, vomiting)

430

carbonic anhydrase

interconverts CO2 + H2 H2CO3

431

How is Cl excreted in parietal cells

HCO3-/Cl- exchanger generates Cl- gradient, then diffuses through channels out

432

Gastrin receptor on parietal cells

CCK3

433

ACh receptor on parietal cells

M3

434

Cholera mechanism

He’s on a stationary bike + there’s tents set up all over the room + swat team is breaking into his house/cholera A-B toxin (a for activating, b for binding) activates adenyl cyclase by ADP ribosylation to increase cAMP. *This leads to increased Cl- secretory channels in crypt cells.

435

CCK has some gastrin-like properties because both CCK and gastrin

Have 5 identical C-terminal amino acids.

436

Monosaccharide transport caveat

Fructose is the only monosaccharide that that is not absorbed by Na+-dependent cotransport. It it stransported by facilitated diffusion.

437

Amino acid absorption in the intestine

Na+-dependent cotransport (*except for oligopeptides)

438

Fatty acid absorption

simple diffusion

439

Why does ileal resection (such as for Crohn's patients) cause steatorrhea?

Ileum normally transports bile acids from the lumen of the gut. Thus, with ileal resection new synthesis of bile acids is needed to replace bile acids that are lost in the feces. With ileal resection most of bile acids secreted are excreted in the feces and the liver pool is diminished. ***Bile acids are needed for micelle formation in the intestinal lumen to solubilize products of lipid digestion so that they can be absorbed. So the problem is MICELLES DO NOT FORM in the intestinal lumen.

440

Where are chylomicrons formed?

Within intestinal epithelial cells and are transported to lymph vessels.

441

Function of CCK

Mediates digestion in the small intestine by inhibiting gastric emptying and decreasing gastric acid secretion. Lines small intestine.

442

Saliva characteristics

1) hypotonic
2) high HCO3- concentration
3) alpha-amylase and lingual lipase

443

control of saliva production

Parasympathetic, thus it is abolished by vagotomy.

444

What are slow waves in small intestinal smooth muscle cells?

oscillating resting membrane potentials.