Teaching Clinic - Optimal Therapies For H. pylori Infection

Question 1

What is the pathogenesis of gastric carcinogenesis?

Answer 1

H.pylori (class 1 carcinogen): chronic gastrititis (can do primary prevention 15-40 years) –> gastric atrophy/intestinal metasplasia (seconary prevention 5-20 year) –> gastric cancer

Question 2

Indications for testing for H.pylori

Answer 2

Question 3

Treatment for H.pylori

Answer 3

PPI + clarithromycin 500mg + amoxicillin 1000mg for 14 days
PPI + clarithromycin 500mg + metronidazole 400mg

Can replace amoxicillin (susceptible) with metronidazole (but will reduce effectiveness due to resistance) if allergic to penicillin

Question 4

Antibiotic resistance of H.pylori

Answer 4

Question 5

Causes for failure of triple therapy

Answer 5

Poor compliance: side effects, duration, multiople pills
Inappropriate dose and duration
Smoking
Old age
Drug resistance

Question 6

Rescue regimen for H.pylori

Answer 6

For 14 days (high non compliance rate –> persuade for at least 10 days)
PPI in standard dose bid
Bismuth subcitrate 120mg qid
Metronidazole 400mg tid
Tetracycline 500mg qid

Question 7

levofloxacin triple regimen as rescue therapy

Answer 7

For 7 days
Lansaprazole 30mg bid
Amoxil 1gm bid
Levofloxacin 200mg bid 7 days

Question 8

Rifabutin triple regimen therapy as rescue therapy

Answer 8

3rd line for 7 days ($2000 a week)

Rabeprazole 20mg bid, rifabutin 300mg daily, levofloxacin 500mg daily