GIT 3

Question 1

Rebound gastric acid hypersecretion when PPI and Antacids withdrawn

Answer 1

↑Gastrin → induces hypertrophy of ECL and parietal cells → over stimulation of parietal cells with hyperfunctioning of unblocked ATPase

Question 2

All antacids cause__

Answer 2

hypokalemia

Question 3

Aluminium hydroxide adverse effects

Answer 3

CHOPS
constipation
Hypophosphatemia,
 Osteodystrophy, 
Proximal muscle weakness, 
Seizures

Question 4

Octreotide: Long-acting somatostatin analog; inhibits secretion of various

Answer 4

splanchnic vasodilatory hormones

Question 5

Sulfasalazine: A combination of ______ and _______. Activated by _______

Answer 5

sulfapyridine (antibacterial) and 5-aminosalicylic acid (anti-inflammatory).

colonic bacteria.

Question 6

Metoclopramide promotes _____ but Does not influence _____

Answer 6

upper GI motility

colon transport time

Question 7

Metoclopramide Drug interaction with _____ and ________

Answer 7

digoxin and diabetic agents.

Question 8

Metoclopramide: Contraindicated in patients with __________

Answer 8

small bowel obstruction, 
Parkinson disease (due to D2-receptor blockade),
↓seizure threshold.

Question 9

Orlistat: MECHANISM

Answer 9

Inhibits gastric and pancreatic lipase

Question 10

___ is sometimes used for refractory chemotherapy induced diarrhea.

Answer 10

Octreotide

Question 11

Weight loss medications

Answer 11

Stimulants (phentermine, benzphetamine, diethylpropion)

orlistat

Bupropion/natrexone

Question 12

Sodium polystyrene resin:

Answer 12

exchanges intraluminal sodium for potassium ion and lowers serum potassium

Question 13

In adenomatous polyps, _____ is most important risk factor for cancer

Answer 13

polyp size
↑risk >10mm

Greatest risk when >4cm

Question 14

Familial adenomatous polyposis
Autosomal dominant mutation of APC tumor suppressor gene on chromosome ______. Mutations lead to _____ accumulation and uncontrolled cell proliferation.

Answer 14

5q22

ß-catenin

Question 15

In FAP ____ is always involved

Answer 15

Rectum

Question 16

in lynch syndrome ____ is always involved

Answer 16

proximal colon

Question 17

Marker for intestinal origin of adenocarcinoma:

Answer 17

Cytokeratin 20

Question 18

Molecular pathogenesis of colorectal cancer

Answer 18

Chromosomal instability pathway: mutations in APC

Microsatellite instability pathway: mutations or methylation of mismatch repair genes (eg, MLH1)

Question 19

Congenital diaphragmatic hernia may occur due to congenital defect of ________

Answer 19

pleuroperitoneal membrane

Question 20

Distal esophagus is attached circumferentially to diaphragm by ______ at __________

Answer 20

phrenoesophageal membrane

gastroesophageal junction

Question 21

Bochdalek hernia is due to _____

Answer 21

failure of posterolateral diaphragmatic foramina to fuse

Question 22

______ is not contained by femoral sheath

Answer 22

femoral nerve

Question 23

Effect of prostaglandin and steroids on LES tone

Answer 23

Prostaglandins → ↓LES tone

Steroids inhibit prostaglandins → ↑LES tone

Question 24

dysphagia, food impaction seen in _____

Endoscopic findings:

Answer 24

Eosinophilic esophagitis

Esophageal rings and linear furrows often seen on endoscopy

Question 25

Schatzki rings Rings: location

Answer 25

at gastroesophageal junction

Question 26

Mechanism of gastritis caused by H. Pylori Gastric duodenal

Answer 26

Gastric: 1. Urea → Ammonium → Ammunium chloride → damage to mucosa 2. Urea → Ammonium → ↑pH → gastrin release → ↑ acid Duodenal: antrum → D cells damage → ↓somatostatin → ↑gastrin → ↑acid → duodenal ulcer

Question 27

Autoimmune gastritis: Autoantibodies to

Answer 27

H+/K+ ATPase on parietal cells and to intrinsic factor.

Question 28

In gastricpresis damage to ------

Answer 28

1. cells of cajal | 2. NO secreting neurons that induce relaxation of fundus of stomach

Question 29

Pain worse at night ------- ulcer

Answer 29

duodenal

Question 30

Suspensory ligament of treitz:

Answer 30

suspends dudeno-jejunal flexure to posterior abdominal wall.

Question 31

Celiac disease: HLA_____

Answer 31

DQ2, DQ8

Question 32

Celiac disease is a _______ hypersensitivity reaction. | ______ has no role in pathogenesis.

Answer 32

Type 4 antibodies. (only helpful for diagnosis)

Question 33

↓ mucosal absorption affecting duodenum and jejunum seen in

Answer 33

Celiac disease | Tropical sprue

Question 34

Tropical sprue is associated with ______ due to ____ deficiency and, later, _____ deficiency.

Answer 34

megaloblastic anemia folate , B12