GI-Rx

Question 1

Olestra

• what is it?
• indication

Answer 1

• non-caloric food additives that mimic taste/texture of triglyceride
• used for weight loss

Question 2

Rifaximin

• MOA
• indication

Answer 2

• ANTIBIOTICS that kills gut flora which GENERATES ammonia

- hyperammonemia

Question 3

How exactly lactulose works to treat hepatic encephalopathy? What is another indication of lactulose? how does it work?

Answer 3

ACIDIFY gut -> convert ammonia into NH4+
* gut flora degrades lactulose into lactic acid

Lactulose is also used as osmotic laxatives, dragging water into gut, inducing diarrhea to treat constipation

Question 4

What treatment can improve dysphagia in achalasia?

Answer 4

CCB
-> reducing intracellular calcium -> dilation of esophageal smooth muscle

• remember:
• low 1/3 of esophagus: smooth muscle
• upper 1/3: striated muscle (dysphagia can happen from myasthenia gravis)
• middle 1/3: mixed

Question 5

What are two physical exam findings for appendicitis? (not including Mcburney sign)

Answer 5

• psoas sign: pain during hip flexion against resistance

- obturator sign: pain during INTERNAL rotation in flexed hip

Question 6

Is markedly elevated AST or ALT common in hepatocellular carcinoma?

Answer 6

NO.

true marker of HCC is alpha fetoprotein

Question 7

What two abnormal electrolytes should I notice in VIPoma?

Answer 7

low potassium

high chloride: achlorhydia -> accumulation of chloride

Question 8

Scleroderma affects which part of esophagus to result in aphasia? striated muscle? or smooth muscle

Answer 8

lower 2/3: smooth muscle (middle 1/3 is mixed striated and smooth)

• this is same for other conditions
  : achlasia, plummer-vinson
• upper 1/3: striated muscle -> aphasia in myasthenia gravis

Question 9

Intussuseception may present as intermittent pain. Why?

Answer 9

partial reversal of obstruction

Question 10

squamous cell carcinoma of esophagus vs. achalasia: how do they present differently in terms of symptom?

Answer 10

squamous cell carcinoma of esophagus
: dysphagia first solid and then progressively worse with liquid

achalasia
: dysphagia BOTH SIMULTANEOUSLY solid and liquid

Question 11

Plummer Vinson syndrome: dysphagia due to esophageal web and iron deificiency anemia. What another condition is associated with it?

Answer 11

glossitis- beefy red tongue

Question 12

palpable non-tender gallbladder: diagnosis?

Answer 12

pancreatic adenocarcinoma

• this physical exam finding is called Courvoisier sign
• PALPABLE, NONTENDER GALL BLADDERis keyword. Other gallbladder diseases (cholelithiasis, choledocholelithiasis) are generally not palpable gallbadder

Question 13

What is choledocholelithiasis?

Answer 13

gallstone in common bile duct (out side of gallbladder)

Question 14

Why misoprostol is contraindicated in pregnancy

Answer 14

uterine contraction, which induces labor