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Flashcards in GI Deck (235):
0

What activities are carried out in Zone 1 vs Zone 3 of hepatic lopules?

Zone 1: adjacent to triad, O2 rich. gluconeogenesis, B-oxidation, AA metabolism, formation of urea

Zone 3: adjacent to central vein, O2 poor. P450 reactions, lipid synthesis, glycolysis

1

What are stellate cells?

Ito cells
Reside w/in Space of Disse
Store lipid and vitam A
Produce reticular fibers
Cirrhosis: multiply and produce large amounts of ECM

2

3 classifications of liver disease

1. Hepatocellular: acute, fulminant, chronic
2. Cholestatic: intrahepatic, extrahepatic
3. Cirrhosis

3

What viruses are associated with hepatocellular injury?

Hepatotropic: Hepatitis A,B,C,D,E

Systemic: EBV, CMV, HSV, enterovirus

4

What are microscopic features of acute hepatitis?

lobular disarray - disruption of architecture
ballooning degeneration
apoptotic bodies (Councilman bodies)
inflammatory infiltrates, activated Kupffer cells
regeneration (with resolution)

5

What is fulminant hepatitis?

Rare variant of acute hepatitis. Rapid onset of liver failure over period of days - weeks.
*Heralded by AMS and coagulopathy*

6

Causes of fulminant hepatitis

Drugs (acetaminophen overdose, antimycobacterial (rifampin, isoniazid), antidepressants (MAOi), halothane, mushroom poisoning)
Virus (HAV, HBV + HDV)
Autoimmune
Ischemia
Metabolic

7

What is chronic hepatitis?

Evidence of ongoing liver injury for >6mos
May be viral (HBV, HDV, HCV), autoimmune or metabolic

8

What is the predominant microscopic feature of chronic hepatitis?

inflammatory infiltrate surrounding portal tracts
fibrosis

9

What is "bridging" necrosis?

Seen in chronic hepatitis
fibrosis / necrosis stretching between portal tracts or from portal tract to central vein

10

What are microscopic indicators of HBV, HCV, and autoimmune hepatitis?

HBV: ground-glass cytoplasm
HCV: microvessicular fatty change and portal tract lymphoid aggregates
autoimmune: plasma cell infiltrates of portal triad

11

What is choledocholithiasis?

gall stones w/in the common bile duct

12

What are the characteristic lab findings assoc. with cholestasis?

Elevated alkaline phosphatase
elevated gamma-glutamyl transferase (GGT)
elevated 5' nucleotidase

13

What hepatic condition presents with the highest aminotrasnferase elevations?

ALT/AST elevation hallmark of hepatocellular necrosis:
Acute Hepatitis 10-30x
Biliary obstruction 1-5x
Cirrhosis 1-3x
Hepatic metastases 1-2x

14

What defines acute liver failure?

Rapid onset of hepatic dysfunction with no underlying liver disease progressing to encephalopathy w/in 8-12 weeks

15

What are symptoms of acute liver failure?

Mental status changes
Jaundice, dark urine, light stool
Seizure
Hypoglycemia
Coagulopathy
Hepatorenal syndrome

16

How is cholestasis diagnosed?

Elevated alkaline phosphatase
Elevated GGT, 5' nucleosidase
Hypercholesterolemia
Hyperbilirubinemia (conjugated)
Prolonged prothrombin time (Vit K deficiency)
Anti-mitochondrial Ab (primary)

Imaging
Liver biopsy

17

What are the physical signs of portal hypertension?

1. Ascites
2. Splenomegaly
3. Abdominal vasculature accentuation

18

3 classifications of portal HTN

Pre hepatic
Intrahepetic
Post hepatic

19

What does TIPS stand for?

Transjugular Intrahepatic Portosystemic Shunt
Performed by interventional radiologist - treatment for portal HTN

20

How do acute and chronic hepatic encephalopathy differ?

Acute: Type A: assoc. w/ acute disease. Delirium and convulsions progressing to coma. BBB and cerebral edema are common.

Chronic: Types B and C: chronic disease: pathogenesis unclear. Asterixis, Hyperreflexia, Mental disturbances, EEG changes
Production of toxic substances by gut bacteria implicated

21

What is therapy for chronic hepatic encephalitis?

Treat precipitating factor
Lactulose
Abx: Rifaximin, neomycin
Liver transplant

22

What does protein content of ascites fluid indicate?

Etiology of ascites
Serum albumin - ascites albumin
if > 1.1, portal HTN likely
Elevated ascites albumin: tumor or chronic infection

23

What are complications of ascites

Spontaneous Bacterial Peritonitis - esp. low protein fluid
Flood's syndrome: ruptured umbilical hernia
Plural effusion
Drug dilution in "3rd space"

24

What is hepatorenal syndrome?

Renal failure w/ accompanying advanced severe liver disease
No ATN (tubules intact - low urine Na+), but severe oliguria

25

How is hepatorenal syndrome diagnosed and treated?

Diagnosis: rule out pre-renal azotemia via trial of fluid expansion
Treatment: Often liver transplant. Dialysis.

26

Primary cause of unconjugated bilirubinemia

Hemolytic jaundice: production of bilirubin in excess of liver's ability to process it.

27

What are the 2 leading causes for liver transplant?

Hep C (45%)
Alcoholic cirrhosis (15%)

28

At what pressure within the hepatic portal vein is variceal bleeding likely?

>12mmHg

29

5 factors that contribute to chronic ascites

1. Portal HTN -> systemic vasodilation, decreased effective bv, SNS activation
2. RAAS activation -> increased Na+
3. ADH -> increased H2O
4. Increased transsinusoidal filtration
5. hypoalbuminemia -> decreased osm

30

What microscopic feature is associated with alcoholic hepatitis?

Mallory bodies or alcoholic hyalin: eosinophilic cytoplasmic inclusions

31

What are transaminase levels in alcoholic hepatitis?

Mild to moderate increase with AST > ALT
vs. viral where ALT > AST

32

Is alcoholic cirrhosis micro or macronodular?

typically micro

33

In what setting does Non-alcoholic Fatty Liver Disease typically present?

Obesity and Insulin resistance.

34

4 metabolic liver diseases

Non-alcoholic fatty liver disease
Hemochromatosis
a1 antitrypsin deficiency
Wilson's disease

35

What mutation is often seen in hemochromatosis?

HFE gene (6p) mutation
Autosomal Recessive

36

What organs are affected by hemochromatosis?

Liver - micronodular cirrhosis, hepatocellular carcinoma
Myocardium - dysfunction
Pancreas - fibrosis, cell loss -> diabetes mellitus
Joints - synovial tissue damage -> arthropathy
Endocrine glands - hypopituitarism -> hypogonadism

37

What is another name for Wilson disease?

Hepatolenticular degeneration
Lenticular = putamen and caudate = basal ganglia

38

What is Wilson's disease?

Autosomal recessive defect in copper ATPase
defective transport in liver -> decreased incorporation into ceruloplasmin and decreased excretion in bile

39

Symptoms of Wilson's disease

Hepatitis / cirrhosis
CNS injury (tremor, rigidity, dysarthria, depression, anxiety, psychosis)
Kaiser-Fleischer rings, sunflower cataracts
Hemolytic episodes

40

What gene is involved in a1-antitrypsin deficiency?

SERPINA-1
Autosomal codominant
chromosome 16: Pi locus: normal = MM, severe = ZZ

41

who should be screened for a1-antitrypsin deficiency?

All people w/ COPD, unexplained liver disease, and 1st degree family members of probands

42

How does a1-antitrypsin deficiency disease cause liver damage?

Accumulation of misfolded, polymerized a1-AT proteins in hepatocyte ER

43

Manifestations of a1-AT deficiency

Panlobular emphysema (esp. basilar)
Hepatitis (neonatal hepatitis), cholestatic jaundice, cirrhosis, hepatocellular carcinoma
Eosinophilic inclusion bodies in hepatocytes

44

Pathology of primary biliary cirrhosis

Autoimmune, Tcell mediated destruction of small - medium bile ducts
Granulomatous destruction of bile ducts w/ chronic inflammatory infiltrate

45

Lab findings in Primary Biliary Cirrhosis

elevated hepatic alkaline phosphatase, GGT, cholesterol, conjugated bilirubin
elevated IgM, antimitochondrial Ab and lipoprotein X

46

What is treatment for PBC?

Urodeoxycholic Acid
Symptomatic treatment (pruritis, osteoporosis, portal HTN)
Liver transplant

47

What is Primary Sclerosing Cholangitis?

progressive destruction of large intra and extrahepatic bile ducts
autoimmune, ANCA assoc., close assoc. with ulcerative colitis
Mostly men <40
Produces alternating stricture and dilation in ducts

48

What are complications of Primary Sclerosing Colangitis?

Progressive biliary obstruction and portal fibrosis
Biliary cirrhosis
Increased risk of cholangeosarcoma

49

What is DILI?

Drug Induced Liver Injury
Most common reason for FDA removal of approved drugs

50

What part of the liver is initially affected by acetaminophen toxicity?

Zone 3 (P450 activity)

51

2 ways in which ETOH contribute to acetaminophen toxicity

Induction of P450 pathway
Depletion of GSH stores

52

First line treatment for acetaminophen OD?

N-acetylcysteine

53

Describe unpredictable / idiosyncratic DILI

Usually latent "sensitization" period before symptoms, more rapid on re-challenge
Associated fever, rash, eosinophilia

54

2 theories to explain unpredictable DILI

1. Hypersensitivity: drug + carrier = macromolecule = neo-antigen -> Immune response -> hepatotoxicity

2. Metabolic + genetic: drug + genetics -> novel metabolite -> liver injury

55

What drugs are associated w/ cholestasis?

Phenothiazines (Chlorpromazine)
Oral Contraceptives (estrogens)
Erythromycin Estolate
Amoxicillin / Clavulanate (augmentin)

56

What effect does Chlorpromazine (thorazine) have on the liver?

Assoc. with cholestasis + inflammation via unknown mechanism
3-5 weeks after initiation of therapy
Resolves w/ discontinuation
PBC-like

57

What effect does Methotrexate have on the liver?

Fatty change related to cumulative dose
Toxicity lower in RA, higher in psoriasis
Liver biopsy in follow up

58

Name some drugs assoc. w/ chronic hepatitis

Acetaminophen
Amiodarone
Aspirin
Dantrolene
Ethanol
Isoniazid
a-methyldopa
Vit-a
nitrofurantoin

59

Name some drugs associated with granuloma formation

Allopurinol
Hydralazine
Penicillin
Quinidine
Sulfonamides, sulfonylureas
a-methyldopa

60

3 drugs associated with "predictable" hepatotoxicity

Acetaminophen
CCl4
Amanita Phalloides

61

What is the cause of dental carries?

Dissolution of inorganic component of tooth by organic acids via microbial metabolism of carbohydrates

62

What microbes are primarily involved in the formation of dental carries?

S. mutans - crown
Lactobacillus - root

63

What is oral tori?

bony overgrowth of palate or lingual side of mandible.
No need for removal unless impedence of function or speech

64

What causes amalgam tattooing?

insoluble silver salt (from silver amalgam filling) deposited in collagen fibers of lamina propria

65

What are Fordyce Spots?

Occurrences of sebaceous glands in oral cavity
not apparent in children, activated at puberty
No clinical significance, found in 82% of population

66

Epulis fissuratum

"denture injury tumor" due to mechanical irritation of ill-fitting denture
Usually no pain or tenderness unless infection is involved

67

Papillomatosis

found on soft tissue of vault of hard palate
numerous papillary projections due to mechanical irritation and ill-fitting denture, food debris

68

Is oral papilloma cancerous?

NO - benign w/ stratified squamous epithelium

69

What is an aphthous ulcer?

Canker sore
Recurrent, superficial ulcer of non-keratinized epithelium
Persist 8-14 days
Causes: psychic, autoimmune, microbial, traumatic endocrine, hereditary
Treatment: tetracycline mouthwash, kenalog in orabase, analgesics

70

What is treatment for oral herpes?

Acyclovir ointment
Systemic acyclovir for immunocompromised patients.

71

What oral ulcers should be considered for biopsy?

Highly suspicious, slow healing ulcers in patients who are poor historians.

72

What is Moniliasis? Culture? treatment?

Oral thrush - Candida albicans
Culture: Sabouraud's agar
Treatment: Nystatin, Ketoconazole, Fluconazole, saline baking soda rinse

73

Oral manifestation of Addison's disease and treatment

Hyperpigmented spots due to pituitary stimulation of melanotrophic activity
treated w/ corticosteroids

74

What are oral manifestations of leukemia?

gingival hyperplasia, gingivitis, hemorrhage, petechia, mucosal ulceration

75

What is Paget's disease, oral manifestations, treatment

Abnormal bone resorption and deposition
Oral: enlargement of maxilla / mandible, spacing of teeth
Treatment: NSAID, ASA, calcitoinin, diphosphonates, mithramycin

76

Oral presentation of Lichen Planus

Pruritic, Purple, Polygonal, Planar, Papules and Plaques
Oral: Wickham Striae: white, lace-like patterns on top of papules
may be erosive - low, but increased risk for malignancy
Yeast infection common
Treat with corticosteroids

77

Oral manifestations of HIV / AIDS

Hairy leukoplakia
Candidiasis
Herpes outbreaks
Kaposi's sarcoma - most frequent malignancy of AIDS

78

What is the organism involved in cat scratch disease?

Bartonella henselae
Children w/ cervical lymphadenopathy referred for dental exam to exclude oral infection

79

In VZV outbreak, when should anti-virals be started?

w/in 72 hours of onset

80

What is leukoplakia?

white patch or plaque on oral mucosa that does not scrape off and cannot be otherwise classified.
Homogenous or Erythroleukoplakia (4-5x increased risk of malignant transformation)

81

Infrequent agents of viral hepatitis

CMV: children, anicteric, no chronicity. May be lethal in immunocompromised
EBV: self-limited mono. 40% have elevated transaminase. no chronicity
HSV: immunocompromised, high mortality. Liver biopsy shows viral inclusion bodies

82

HBV genome

incomplete dsDNA

83

HAV genome

ssRNA

84

How is HAV transmitted?

fecal-oral route - contaminated food and water

85

How is Hep A diagnosed?

IgM antibody: current infection
IgG antibody: previous infection

86

HAV therapy

Supportive
Infection spontaneously clears - no carrier state

87

How does Hep B result in death?

Cirrhosis w/ liver failure
Hepatocellular carcinoma

88

What is vertical transmission?

Mother to child

89

What is the gold standard for diagnosis of HBV?

Serum HBV DNA by PCR

90

If acute HBV infection is suspected, what test should be ordered to confirm?

IgM anti-HBVc

91

What marker is seen in patients immunized against HBV?

IgG anti-HBs

92

What is the earliest detectable Ab in HBV infection?

IgM anti-HBs

93

What does the presence of anti-HBcAg indicate?

Exposure to virus. will be positive for life.

94

What ethnicity has the highest rate of HBV carriage in USA?

Asian

95

Most commonly used HBV medications

entecavir (guanosine analog)
tenofovir (adenosine analog)

both inhibit HBV RT

96

Post-exposure treatment for HBV

HB immunoglobin
HB vaccine

97

By age, what % of HBV infected patients will become chronic carriers?

Infant: 90%
1-5 yrs: 30%
Adult: 5-8%

98

What does HDV require for replication?

HBsAg

99

Which has a worse prognosis HBV + HDV co-infection of superinfection

superinfection: 90% develop chronic liver disease, 80% cirrhosis w/in 5 years

co-infection: 2% develop chronic disease. Co-infection is typically self-limited and resembles acute Hep B

100

What is treatment of HDV?

HBV treatment!

101

In HCV infection, what is assumed with symptoms of chronic liver disease?

End Stage Liver Disease has occurred.

Acute Hepatitis rare, usually asymptomatic until late in course

102

What is Von Meyenberg Complex?

Bile duct hamartomas - non neoplastic - persistence of embryonic structure
Collection of small, irregular bile ducts in fibrous tissue
Multiple small, pale spots on liver

103

3 non-neoplastic tumors of liver

1. Von Meyenberg Complex
2. Nodular Hyperplasia (oral contraceptives, anabolic steroids)
3. Nodular Regenerative Hyperplasia: regenerative nodules w/o fibrosis

104

Complication of Nodular regenerative hyperplasia of liver

Portal HTN

105

What is the most common benign hepatic tumor?

Cavernous hemangioma

106

What is hepatic cell adenoma associated with? appearance?

Young women taking contraceptives (long-term)
Solitary, well circumscribed, soft green mass lacking portal tracts

107

Complication of hepatic adenoma?

Hemorrhage - acute onset of RUQ pain

108

What is the risk of malignant transformation in hepatic adenoma?

Very small risk
B-catenin gene: elevated risk if present

109

Malignancies that most frequently metastasize to the liver

Lung, GI (colon), pancreas, breast

110

What lab abnormalities are found in tumors that have metastasized to the liver?

early: alkaline phosphatase and lactate dehydrogenase
Late: serum bilirubin and ALT / AST levels

111

3 major risk factors for hepatocellular carcinoma

HBV carrier state (incorporation into cellular DNA -> oncogene activation and HBV X-protein expression)
Cirrhosis (repetitive regenerative cycles -> mutations (RAS, p53, etc))
Exposure to aflatoxin (p53 mutation)

112

What is Budd-Chiari?

Occlusion of IVC or hepatic veins w/ centrilobular congestion and necrosis
Sudden liver enlargement, pain, and ascites
May occur w/ hepatocellular carcinoma

113

What lab abnormalities may be seen in hepatocellular carcinoma?

a-fetoprotein: neither sensitive nor specific
ALP and LD elevation
Late: bilirubin and ALT/AST elevation

114

What is an important variant of hepatocellular carcinoma?

Fibrolamellar variant
young adults, no predisposing factors, otherwise normal liver
well differentiated tumor cells in dense fibrous stroma w/ parallel collagen lamellae
Good prognosis

115

Risk factors for cholangiocarcinoma

Primary sclerosing cholangitis
Congenital biliary tract structural abnormalities
Thorotrast exposure
Chronic parasitic biliary tract infection (Opisthorchis sinensis)

116

What is angiosarcoma?

Endothelial tumor - hemorrhagic nodules and blood filled cysts
In liver associated with vinyl chloride, thorotrast, arsenic exposure

117

What is hepatoblastoma?

tumor of young children
large, soft, hemorrhagic, necrotic mass
microscopic: small, round blue cells. epithelial mesenchymal differentiation

118

What marker is elevated in hepatoblastoma?

a-fetoprotein

119

2 functions of bile

absorption of fat via formation of micelles
rid body of cholesterol via bile salts and bilirubin

120

What is a choledocal cyst?

Dilation or outpouching of common bile duct

121

2 causes of biliary atresia

1. Hypoplasia or aplasia (rare)
2. Idiopathic neonatal bile duct destruction (several weeks after birth)

122

What is the most common type of gallstone in US?

Cholesterol

123

How are cholesterol gallstones formed?

supersaturation of bile with cholesterol + bile stasis -> crystal nucleation

124

Risk factors for cholesterol gallstones

Due to excess cholesterol secretion (+/- decreased bile salt secretion)
-Estrogens (contraceptive use)
-Age
-Obesity / rapid weight loss
-Inherited metabolic disorders

125

How do cholesterol gallstones appear on xray?

radiolucent

126

2 types of pigment gallstones and causes.

1. black stones: chronic hemolysis. Unconjugated bilirubin precipitates with Ca++
2. brown stones: assoc. with biliary tract infections (Flukes)

127

2 causes of acute cholecystitis

1. calculus: stone obstructs neck of gallbladder or cystic duct -> distention and vascular compression
2. acalculus: critically ill patients - biliary sludge obstructs cystic duct -> poor biliary perfusion, possibility of infection

128

What is seen on CBC in acute cholecystitis?

elevated WBC, esp. neutrophils

129

What are Rokitansky-Aschoff sinuses?

Feature of chronic cholecystitis
mucosal diverticula w/in gallbladder wall

130

What is a significant risk factor for cancer of the gallbladder?

Porcelain gallbladder : dystrophic calcification

131

Prognosis for carcinoma of the gallbladder?

very poor - diagnosis frequently incidental
Frequent local invasion of liver, and adjacent viscera
Metastasis to lymph nodes, peritoneum, lungs

132

What is a Klatskin tumor?

tumor at origin of common bile duct- slowly progressive
Subtype of carcinoma of extrahepatic bile duct

133

3 regulators of pancreatic exocrine function

Vagus nerve
CCK: HCO3- secretion
Secretin: zymogen secretion

134

How is trypsin activated?

Trypsin (from pancreas) activated by enterokinase on brush border of duodenum

135

Systemic and local complications of acute pancreatitis

Systemic:
-DIC
-ARDS
-ARF (shock -> ATN -> ARF)
-metabolic hypocalcemia, hypoalbuminemia, hyperglycemia, acidosis)

Local:
-pseudocyst, abscess, biliary / duodenal obstruction

136

What defines chronic pancreatitis and what are symptoms?

Frequently relapsing inflammation -> progressive pancreatic injury
Usually alcohol related
May be CF, obstruction, idiopathic
Symptoms: pain, loss of function (malabsorption, DM), biliary / duodenal obstruction

137

Differentiate true pancreatic cysts from pseudocysts

true cysts: lined with epithelium, associated with ADPKD, VHL

pseudocysts: complications of pancreatitis - no epithelial lining

138

What are risk factors for pancreatic adenocarcinoma?

Smoker, male, black, Native American, high fat diet, nitrosamine exposure, diabetes mellitus

139

What part of the pancreas is most frequently involved in adenocarcinoma?

Head > body > tail

140

How does pancreatic cancer usually spread?

Local:
Head: duodenum, common bile duct
Body and Tail: vertebrae, retroperitoneal and abdominal organs
Metastasis:
lymph nodes, liver

141

What causes hereditary pancreatitis?

Autosomal Dominant
Mutation of trypsinogen on chromosome 7
Trypsin is resistant to lysis -> prolonged activity

142

What are lab findings in acute pancreatitis?

Lipase and amylase 3x normal (lipase more specific for pancreas)
AST 2x (gallstone)

143

What imaging studies are preferred in diagnosis of acute pancreatitis?

Initial: ultrasound
Prognosis: CT - specific and indicates extent of necrosis -> complication / mortality risk

144

According to Ranson's criteria, what features on admission are suggestive of gallstone pancreatitis?

Age >70
WBC/mm^3 >18,000
Glucose (blood) >220
LDH >400

145

What organisms are most frequently involved in necrotizing pancreatisis?

E. coli
Klebsiella
Enterococcus

146

How is infected pancreatic necrosis treated?

surgical debridement
Abx use is controversial

147

Should pancreatic pseudocysts be treated?

Only if symptomatic

148

What is a Bentiromide test?

Test of pancreatic function. Oral dose given (Bentiromide has PABA linked) chymotrypsin cleaves, frees PABA for absorption and renal excretion.
Low PABA in urine indicates decreased pancreatic function

149

How is a secretin stimulation test performed?

IV secretin given
Tube placed in pancreatic duct, timed periodic collections measuring for HCO3- levels: low indicates chronic pancreatitis
Cumbersome, unpleasant, rarely done

150

What is the role of the Schilling test in pancreatitis diagnosis / treatment?

Pancreatitis -> reduced absorption of fat soluble vitamins (B)
Schilling test will be abnormal
Administration of pancreatic enzymes will normalize Schilling test, suggesting chronic pancreatitis

151

At what point in pancreatic disease is steatorrhea usually apparent? How is it treated?

90% loss of lipase activity

Supplement pancreatic enzymes w/ 30,000 IU lipase activity at each meal
Acid suppression and low-fat diet

152

Pancreatic adenocarcinoma 5 year survival rate

<5%

153

What are some indications for cholecystectomy?

Symptomatic gallstones, hemolytic anemia, gastric bypass, porcelain bladder, gallbladder adenoma >1-2cm

154

What is a drug that can be used to treat cholesterol gallstones

Ursodeoxycholic acid
Inhibits HMG coA reductase -> reduced cholesterol production
Reduces hepatic cholesterol secretion in bile

155

What is cholangitis?

Infection of the common bile duct
Usually gram neg organisms. can spread to liver and blood.
Charcot's triad: pain, fever, jaundice

156

3 risk factors for carcinoma of the extrahepatic biliary ducts

In Asia: parasites - Chloronorchis sinensis, infections, IBD, sclerosing cholangitis

157

What is sudan black staining used for?

Sudan black stain of stool: shows excess fat in stool (steatorrhea) chronic pancreatitis

158

Describe venous drainage of esophagus

Upper 1/3: SVC
Mid 1/3: Azygos
Lower 1/3: Hepatic portal vein via L. gastric (coronary) vein

159

What is the muscular distribution of the esophagus?

Upper 1/3: Skeletal
Mid 1/3: Mixed
Lower 1/3: Smooth

160

What are Auerbach and Meisner's plexuses?

Auerbach: peristalsis
Meisner: sensory

161

What is EGD used for?

Esophagogastroduodenoscopy: used to visualized epithelium of esophagus, stomach, duodenum. Allows biopsy capability.

162

3 components of swallowing (esophageal phase

Primary: swallow-initiated
Secondary: stretch-initiated
Tertiary: uncoordinated, non-propulsive

163

What factors can trigger diffuse esophageal spasm?

Stress, very hot or very cold liquids

164

What happens with the lower esophageal sphincter in Diffuse Esophageal Spasm?

Normal function is preserved.

165

How does scleroderma affect the esophagus?

Collagen deposition in smooth muscle -> aperistalsis in distal esophagus
Incompetent LES

166

How are strictures and obstructive ring lesions of the esophagus usually treated?

Dilation - usually balloon or bougie
Surgery - uncommon

167

What are possible pharmacological treatments for GERD

Acid suppressors (H2RA, PPI, antacid)
Prokinetics (metoclopramide, domperidone, cisapride)

168

Where are Meissner and Auerbach plexuses located in esophagus?

Meissner: within the submucosa
Auerbach: between layers of muscularis propria

169

What are pulsion diverticula and 2 examples

Outpouchings of esophagus due to high pressure
1. Zenker: hypopharynx: between inferior pharyngeal constrictor and cricopharyngeus
2. Epiphrenic: just above LES: associated w/ motility disorders (achalasia, hiatal hernia)

170

What causes an esophageal traction diverticulum?

Continuous external traction - mediastinal inflammation / fibrosis
Located mid-esophagus

171

Who is most at risk for esophageal webs?

Middle aged women

172

Plummer-Vinson

Esophageal webs, iron-deficiency anemia, glossitis, cheilosis, koilonchia (spoon nails)
Increased risk for pharyngeal and esophageal carcinoma

173

2 examples of esophageal rings

A ring: proximal to GE junction

B ring: located at squamo-columnar GE junction. Almost always associated w/ hiatal hernia

174

2 subtypes of hiatal hernias

1. Sliding: GE junction and portion of stomach slide through esophageal hiatus
2. Paraesophageal: "rolling" portion of fundus prolapses into thorax adjacent to esophagus. GE junction stays in abdomen.

175

2 esophageal lacerations

1. Mallory-Weiss: after prolonged vomiting / retching as w/ ETOH intox. superficial longitudinal tears at GE junction
2. Boerhaave: distal esophageal rupture -> mediastinitis - catastrophic event

176

3 types of esophagitis

1. Iatrogenic: (radiation, GVHD)
2. Infectious: immunocompromise: candida, HSV
3. Reflux: GERD

177

Complications of Barret's Esophagus

Epithelial dysplasia
Adenocarcinoma

178

How many layers of muscle surround the stomach?

3 layers of smooth muscle: innermost oblique, inner circular, outer longitudinal

Note: Auerbach's plexus between circular and longitudinal

179

3 etiologies of gastric ulceration

1. NSAID use
2. Intracranial trauma: vagal stimulus -> increased gastric H+ secretion
3. Physiologic stress (shock, sepsis, burns): decreased perfusion of gastric mucosa, systemic acidosis (-> decreased HCO3-)

180

What are Cushing and Curling ulcers?

Cushing: gastric ulceration due to intracranial injury
Curling: gastric ulceration assoc. with burns

181

What is the most common cause of chronic gastritis?

H. pylori infection (90% of cases)

182

H.pylori virulence factors

flagella
urease (urea -> NH3 -> neutralization of acid)
Lewis antigens: allow adherence to gastric foveolar epithelium
toxins

183

3 diagnostic tests for H.pylori

1. H. pylori fecal Ag test
2. Carbon labeled Urea breath test (detects exhaled labeled CO2)
3. H. pylori serology: not helpful for post-treatment follow up

184

What happens in autoimmune gastritis?

Uncommon
CD4+ cells lose tolerance for parietal cell antigens -> anti parietal cell and anti-IF antibodies
Hyperplasia of G cells -> increased gastrin production
B12 deficiency

185

How is the spinal cord affected by autoimmune gastritis?

B12 deficiency -> demyelination of neurons
Posterior and lateral columns most effected -> loss of position and vibratory sensation (leg > arms) w/ sensory ataxia

186

What are the most common locations for gastric ulcers

proximal duodenum > antrum > elsewhere

187

Clinical presentation of gastric ulcer

Recurrent epigastric pain - worse at night and few hours post-meal
-relieved w/ food and alkalai

188

Describe Menetrier disease

Excessive productin of TNF-a -> hyperplasia of foveolar mucous epithelium and atrophy of parietal and chief cells
Protein loss
increased risk of gastric adenocarcinoma

189

What is Zollinger-Ellison Syndrome?

Gastrin secreting tumor -> intractible peptic ulcer disease and mucosal hyperplasia (esp. parietal cells)

190

How is peptic ulcer disease diagnosed?

History and physical
EGD
Upper GI series (75% sensitivity)

191

What patients can be tested and treated for H. pylori w/o undergoing endoscopy?

Patient <45 w/ ulcer symptoms and no alarm signs or complications

192

What NSAIDS are "high risk" for Ulcer development?

Indomethacin
Ketorolac
Piroxicam

193

Who is a candidate for co-administration of NSAID and acid suppressive agent?

Patient requiring chronic NSAID use and having at least 1 risk factor for development of gastric ulcer (>60 yoa, multiple NSAID, corticosteroid or anticoagulant use, Hx of PUD or GI complications)

194

2 prokinetic agents that can be used to treat gastroparesis

1. Dopamine antagonist: DA has anti-motility action on GI
2. 5-HT agonist: Serotonin stimulates motility

195

What is the preferred drug for hospitalized patients w/ gastroparesis?

Eythromycin: motilin receptor agonist

196

What is the MOA of Metoclopramide?

D2 antagonist
5-HT4 agonist
Accelerates gastric emptying in treatment of gastroparesis

197

What is the treatment of choice for variceal bleeding?

Endoscopic sclerotherapy
Endoscopic ligation is also acceptable

198

In a patient with an active GI bleed, when should PPI be given?

Post-endoscopy. No value to Pre-endoscopy admin.

199

Drugs used to treat ulcerative colitis

5-aminosalicylates: oral - active management, maintain remission
rectal - most effective for patients w/ proctitis
corticosteroids: suppress migration of PMNs. Used for management of acute / extensive disease.
Immunomodulators (6MP, Azathioprine): if corticosteroid unresponsive

200

What receptors are found in high density in the emesis center of the medulla?

5-HT3
M1
H1

201

Treatment for hypertrophic pyloric stenosis

pyloromyotomy

202

What is Meckel diverticulum? complication?

Failure of embryonic vitelline duct to involute
Often contains heterotropic foci (gastric mucosa) -> gastric acid production -> GI bleeding, pain, perforation

203

What serology can be used to diagnose Celiac Disease?

Anti-gliadin Ab
Anti-tissue transglutaminase Ab

204

What is the dermatologic presentation of celiac sprue? Cause?

Dermatitis Herpetiformis: Pruritic vessicles that form on back and extensor surfaces of extremities
Caused by anti-gliadin IgA

205

What is Abetalipoproteinemia?

Autosomal recessive
Deficient apoprotein B -> defective lipid transport -> lipid accumulation in enterocytes
Vacuolization of enterocytes, acanthocytes

206

Is celiac sprue associates w/ malignancy risk?

Yes
Non-Hodgkin's Lymphoma
Sm. intestinal adenocarcinoma
Sq. cell carcinoma of esophagus

207

What is Whipple Disease?

bacterial infection affecting middle-aged white men
Tropheryma whippelli
PAS+ macrophages (foamy) fill lamina propria of sm. intestine
also affects joints, brain, heart valves
-> chronic malabsorption, arthropathy, lymphadenopathy, hyperpigmentation, psychiatric complaints, cardiac dysfunction

208

Where are GI carcinoid tumors usually found?

Appendix, ileum, rectum

209

Where do MALT lymphomas generally develop? What is a common associated disorder?

stomach > sm. intestine > colon

Very often associated w/ H. pylori infection

210

What are important factors that go with Burkitt's Lymphoma?
(genetics, infections)

c-myc gene translocation (t[8;14])
latent EBV infection
HIV associated

211

What is GIST and what is it associated with (origin, genetics)?

Gastrointestinal stromal tumor - from interstitial cells of Cajal
Varying malignant potential
mutations: c-KIT, PDGFRA: tyrosine kinase receptors

212

How does steatorrhea -> renal stones?

Malabsorbed FAs bind Ca++ which would normally bind oxalate in the colon
Oxalate is then available for colonic reabsorption -> renal oxalate stones

213

How does smoking effect the risk of developing either of the 2 forms of IBD?

Crohn's: current and former smokers - increased risk of developing
Ulcerative Colitis: former and non-smokers have increased risk

214

What serum markers are found in Crohn's and UC?

Ulcerative Colitis: p-ANCA (60-80%)
Crohn's: ASCA: (70%)

215

What is recommended for colon cancer surveillance in UC and Crohn's?

Colonoscopy every 2 years w/ multiple biopsy after 8-10 yrs. of diagnosis

216

What are some causes of sm. bowel obstruction?

#1: adhesions from prior surgery
Other: hernia, crohn's, volvulus, neoplasm, foreign body

217

What is open loop vs. closed loop bowel obstruction?

Open loop: Intestinal flow blocked, but decompression possible via vomiting

Closed loop: Inflow and outflow blocked -> gas and secretion accumulation w/ no means of decompression

218

what is obstipation?

inability to pass flatus or feces
sign of obstruction along w/ pain, vomiting and distension

219

What organisms tend to flourish in sm. bowel obstrution?

E.coli
Klebsiella
S.faecalis
Normally sm. intestine is nearly sterile

220

Outline treatment for intestinal obstruction

IV fluids (NaCl, lactated ringer's) - monitor electrolytes
Add KCl if needed after adequate urine formed
NG tube - decompression, avoid aspiration of stomach contents
Imaging - monitor - surgery if no resolution

221

What cancers are associated with Peutz-Jeghers?

colon, pancreas, breast, testicular, ovarian, cervical

222

What ovarian cells do LH and FSH work on respectively and what is the effect?

Rising FSH (folicular phase) induces increase in LH receptors in Theca
LH works on Theca cells -> androgen production (Prog, Androstenedione, T) Theca lacks aromatase
FSH works on granulosa cells -> Estradiol from androgens Granulosa cells lack 17a-hydroxylase

223

What causes the LH surge and what is its effect?

increasing estradiol levels -> pos. feedback @ hypothalamus -> LH surge -> ovulation
**Ovulation 36 hrs. after surge**

224

What genes are involved in migration of GnRH secreting neurons? What is the route of migration?

Genes: Kal-1 (encodes for Anosmin), Kal-2, Prox-2

Migration from olfactory placode to Arcuate Nucleus of medial basal hypothalamus

225

Primary amenorrhea

Absence of menses by 16 regardless of growth / pubertal dev
-or-
Absence of menses by 13 w/o dev. of 2ndary sex characteristics

226

Secondary amenorrhea

lack of menses for 3 cycles

227

What is idiopathic hypogonadotrophic hypogonadism? subtype?

Functional congenital absence of GnRH secretion

Kallman: defective migration of GnRH cells and formation of olfactory bulb: IHH + anosmia and other defects

228

What is the cause of Functional Hypothalamic Amenorrhea? How is it diagnosed?

No pathologic disease found
Eating disorders, weight loss, exercise, stress
Low leptin levels believed to be involved - neg. impact on GnRH secretion
Diagnosis: Estrogen <50pg/mL; no withdrawal bleeding on Progesterone challenge

229

Female Athletic Triad

Disordered eating
Menstrual dysfunction
Osteoporosis

230

What are treatments for hyperprolactinemia?

DA agonists: bromocriptine, cabergoline
Surgery if adenoma

231

What is the most common cause of gonadal dysgenesis in women?

Turner syndrome (X0)
Accelerated postnatal follicular atresia -> primary amenorrhea
High LH and FSH, but low estrogen

232

With what disease is Premature Ovarian Failure associated?

Fragile X Syndrome: CGG repeat amplification (usually >500)
Also: autoimmune oophoritis (polyglandular autoimmune disease)

233

Describe the pathogenesis of Polycystic Ovary Syndrome

Elevated LH production -> excess androgen production by theca cells
Depressed FSH production -> low estrogen level, depressed follicle maturation
Insulin intolerance contributes to androgen production by theca cells
Obesity -> increased adipose -> aromatization of androgen -> estrone -> promotes high LH, low FSH

234

Rotterdam criteria for PCOD

2+ of the following:
1) Menstrual irregularity (amen or oligo (<9/yr))
2) Hyperandrogenism / -emia
3) 12+ follicles 2-9mm / ovary

**Other causes of hyperandrogen ruled out**