TABLE 1.

Summary of efficacies of selected antimicrobial agents alone or in combination against infection of gnotobiotic piglets with H. pylori

Therapy and antimicrobial tested	Dosage	Clearance (no. of piglets from which infection was cleared/total no.)a	Eradication (no. of piglets from which infection was eradicated/total no.)b
Triple therapy
Bismuth subsalicylate	5.7 mg/kg QID
Metronidazole	4.4 mg/kg QID	6/6	6/6
Amoxicillin	6.8 mg/kg QID
Dual therapy
Omeprazole	5.0 mg BID
Amoxicillin	5.6 mg/kg QID	6/6	4/4
Monotherapy
Bismuth subsalicylate	5.7 mg/kg QID	5/7	2/8
Erythromycin	6.6 mg/kg QID	2/4	1/4
Omeprazole	5.0 mg BID	0/6	0/4
Ranitidine	1.6 mg/kg QID	0/4	0/4
Tetracycline	7.1 mg/kg QID	4/4	0/4
Amoxicillin	5.6 mg/kg QID	8/8	6/6
Amoxicillin	0.9 mg/kg QID	3/3	3/3
Amoxicillin	0.5 mg/kg QID	3/4	4/4
Amoxicillin	0.1 mg/kg QID	4/6	0/4
Amoxicillin	0.01 mg/kg QID	0/3	0/3
Ciprofloxacin	7.3 mg/kg QID	4/4	4/4
Ciprofloxacin	1.0 mg/kg QID	4/4	0/4
Metronidazole	4.4 mg/kg QID	5/5	5/5
Metronidazole	2.5 mg/kg QID	3/3	3/3
Metronidazole	0.5 mg/kg QID	2/4	2/4
Metronidazole	0.1 mg/kg QID	1/3	1/3
Clarithromycin	5.0 mg/kg QID	5/5	5/5
Clarithromycin	1.0 mg/kg QID	0/4	0/4
Nitrofurantoin	5.0 mg/kg QID	4/4	0/4
Nitrofurantoin	1.6 mg/kg QID	1/5	0/5
Untreated, infected controls (vehicle only or no treatment)		0/24c	0/25d

^aClearance was determined by microbial culture of gastric aspirates collected on the morning after the cessation of therapy. 

^bEradication was determined by microbial culture of gastric mucosa 2 weeks after the cessation of therapy. 

^cIn two additional piglets, infection was not detected by culture of gastric aspirates due to bacterial overgrowth of plates by a contaminant (Escherichia coli). Infection was detected in these two piglets at necropsy on day 31. 

^dOne piglet died of a congenital cardiac anomaly (ventricular septal defect) unrelated to treatment between days 17 and 31 of age.