The effect of intragastric acidity on Helicobacter pylori eradication with bismuth-metronidazole-amoxicillin.
OBJECTIVE
Adding an acid secretion inhibitor to anti-H. pylori regimens may be potentially valuable for enhancing the effectiveness of antimicrobials that exhibit markedly reduced activity at low pH. This study was conducted to evaluate intragastric acidity as a factor in H. pylori eradication with bismuth-based triple therapy.


METHODS
Forty patients with duodenal ulcer and H. pylori infection were included. The patients were divided into 2 groups--normacid (n = 20) and hyperacid (n = 20)--based on the amount of time that 24-hour intragastric pH took to reach the level pH > or = 3. All patients received bismuth subsalicylate (600 mg 3 times daily), metronidazole (500 mg 3 times daily) and amoxicillin (500 mg 3 times daily) for 2 weeks. Then, all patients continued treatment with ranitidine (150 mg twice daily) for 8 weeks prior to the follow-up examination. Blood samples were collected before treatment for measurement of fasting gastrin and pepsinogen-I.


RESULTS
Nine patients (45%) in the normacid group and 8 patients (40%) in the hyperacid group reported side effects. However, there were only 2 patients (10%) in each group who withdrew from the study due to intolerance of side-effects. There was no difference in the H. pylori eradication rate between the normacid and hyperacid groups (16/18, 88.9% vs. 15/18, 83.3%).


CONCLUSIONS
Without co-administration of anti-secretary agents, intragastric acid is not a significant factor in the effectiveness of H. pylori eradication with bismuth-based triple therapy.
Chang
C S
CS
Department of Internal Medicine, Taichung Veterans General Hospital, Taiwan.
Yang
C Y
CY
Wong
F N
FN
Chen
G H
GH
Lien
H C
HC
Yeh
H Z
HZ
Poon
S K
SK
D000328:Adult; D000368:Aged; D000658:Amoxicillin / Q000008:administration & dosage*; D000863:Antacids / Q000008:administration & dosage*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D000897:Anti-Ulcer Agents / Q000008:administration & dosage; D001729:Bismuth / Q000008:administration & dosage*; D004359:Drug Therapy, Combination; D004381:Duodenal Ulcer / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D005260:Female; D005745:Gastric Acidity Determination; D005755:Gastrins / Q000097:blood; D016481:Helicobacter Infections / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008795:Metronidazole / Q000008:administration & dosage*; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009942:Organometallic Compounds / Q000008:administration & dosage*; D010406:Penicillins / Q000008:administration & dosage*; D020116:Pepsinogen A / Q000097:blood; D011899:Ranitidine / Q000008:administration & dosage; D012459:Salicylates / Q000008:administration & dosage*
D000863:Antacids; D000900:Anti-Bacterial Agents; D000897:Anti-Ulcer Agents; D005755:Gastrins; D009942:Organometallic Compounds; D010406:Penicillins; D012459:Salicylates; D008795:Metronidazole; C015715:bismuth subsalicylate; D000658:Amoxicillin; D011899:Ranitidine; D020116:Pepsinogen A; D001729:Bismuth