14-day Susceptibility-guided Bismuth Quadruple Therapy for Multiple Drug Resistant H. Pylori Infection

The investigators define successful eradication as a negative 13C-urea breath test or a negative H. pylori stool antigen test at 4 to 6 weeks after the completion of H. pylori eradication and discontinuation of antibiotics and proton pump inhibitors. The eradication rates are determined by intention-to-treat and per-protocol analyses. The intention-to-treat analysis evaluates all enrolled participants. The per-protocol analysis evaluates those who take >= 80% of the study medications and receive post-treatment 13C-urea breath test or an H. pylori stool antigen test. The successful rate is represented with a percentage (%).

Adverse events are assessed by a physician and a format questionnaire survey after the end of treatment. Serious adverse events are defined as daily activities restricted or participant unable to work. The adverse events include dizziness, skin rash, headache, unpleasant taste/bitter, abdominal pain, nausea, vomiting, diarrhea, constipation, abdominal fullness, glossitis/sore throat, darkened stool, fatigue, anorexia, chest burn, palpitation, and vaginal discharge. All adverse events are classified as none, mild (not restricting daily activities), or serious (restricting daily activities or causing inability to work).

Adherence to medications is evaluated by questionnaire surveys after treatment completion. Adherence of medications is categorized as good (≥ 80% medication taken) or poor (< 80% medication taken).

The eradication rates are evaluated in females and males, respectively. The investigators define successful eradication as a negative 13C-urea breath test at least four weeks after the completion of H. pylori eradication and discontinuation of antibiotics and proton pump inhibitors. The eradication rates are determined by ITT and PP analyses. The ITT analysis evaluates all enrolled participants. The PP analysis evaluates those who take >= 80% of the study medications and receive post-treatment 13C-urea breath test. The staffs assessing antibiotic sensitivity and the 13C-urea breath test are blinded.

The eradication rates are evaluated in the four regimens, respectively. The investigators define successful eradication as a negative 13C-urea breath test at least four weeks after the completion of H. pylori eradication and discontinuation of antibiotics and proton pump inhibitors. The eradication rates are determined by ITT and PP analyses. The ITT analysis evaluates all enrolled participants. The PP analysis evaluates those who take >= 80% of the study medications and receive post-treatment 13C-urea breath test. The staffs assessing antibiotic sensitivity and the 13C-urea breath test are blinded.

The eradication rates are evaluated in the subjects with triple-resistant infection and those with quadruple-resistant infection, respectively. The investigators define successful eradication as a negative 13C-urea breath test at least four weeks after the completion of H. pylori eradication and discontinuation of antibiotics and proton pump inhibitors. The eradication rates are determined by ITT and PP analyses. The ITT analysis evaluates all enrolled participants. The PP analysis evaluates those who take >= 80% of the study medications and receive post-treatment 13C-urea breath test. The staffs assessing antibiotic sensitivity and the 13C-urea breath test are blinded.

The eradication rates are evaluated in the subjects with naïve, those with once treatment failure experience, those with twice treatment failure experience, those with thrice treatment failure experience, those with four-time treatment failure experience, and those with five-time treatment failure experience, respectively. The investigators define successful eradication as a negative 13C-urea breath test at least four weeks after the completion of H. pylori eradication and discontinuation of antibiotics and proton pump inhibitors. The eradication rates are determined by ITT and PP analyses. The ITT analysis evaluates all enrolled participants. The PP analysis evaluates those who take >= 80% of the study medications and receive post-treatment 13C-urea breath test. The staffs assessing antibiotic sensitivity and the 13C-urea breath test are blinded.