Table 3. Recommended options for first-line therapy for Helicobacter pylori infection.

H. pylori antimicrobial susceptibility		Suggested treatment
Known
	Susceptible to CLA and to MET	PPI-AMO-CLA 14 d or Sequential therapy 10 d
	Resistant to CLA, susceptible to MET	PPI-AMO-MET or BIS-PPI-AMO (TET)-MET 14 d*
	Resistant to MET, susceptible to CLA	PPI-AMO-CLA or BIS-PPI-AMO (TET)-MET 14 d*
	Resistant to CLA and to MET	PPI-high dose AMO-MET 14 d or BIS-PPI-AMO (TET)-MET 14 d* or concomitant therapy 14 d
Unknown		PPI-high dose AMO-MET 14 d or BIS-PPI-AMO (TET)-MET 14 d* or concomitant therapy 14 d

CLA: clarithromycin, MET: metronidazole, PPI: proton pump inhibitor, AMO: amoxicillin, BIS: bismuth, TET: tetracycline.

Sequential therapy: PPI-AMO 5 day→PPI-CLA-MET 5 day.

Concomitant therapy: PPI-AMO-MET-CLA 14 day.

^*In the case of penicillin allergy: if the strain is susceptible to CLA and MET, use standard dose triple therapy with MET in place of AMO; if the strain is resistant to CLA, then use BIS-based quadruple therapy with TET instead of AMO if older than 8 years.

Modified from Jones et al. (J Pediatr Gastroenterol Nutr 2017;64:991-1003) [4].