Comparison of Epsilometer test and agar dilution method in detecting the sensitivity of Helicobacter pylori to metronidazole / 北京大学学报(医学版)

OBJECTIVE@#Agar dilution method (ADM) was used as the golden standard to evaluate the consistency of Epsilometer test (E-test) in detecting the sensitivity of Helicobacter pylori (H. pylori) to metronidazole.@*METHODS@#From August 2018 to July 2020, patients with H. pylori infection treated for the first time in Peking University Third Hospital for gastroscopy due to dyspepsia were included in this study. Gastric mucosas were taken from the patients with H. pylori infection. H. pylori culture was performed. Both the ADM and E-test were applied to the antibiotic susceptibility of H. pylori to metro-nidazole, and the consistency and correlation between the two methods were validated.@*RESULTS@#In the study, 105 clinical isolates of H. pylori were successfully cultured, and the minimum inhibitory concentration ≥ 8 mg/L was defined as drug resistance. Both ADM and the E-test showed high resistance rates to metronidazole, 64.8% and 62.9%, respectively. Among them, 66 drug-resistant strains were detected by ADM and E-test, and 37 were sensitive strains, so the consistency rate was 98.1%. Two strains were evaluated as drug resistance by ADM, but sensitive by the E-test, with a very major error rate of 1.9%. There was zero strain sensitive according to ADM but assessed as resistant by the E-test, so the major error rate was 0%. Taking ADM as the gold standard, the sensitivity of E-test in the detection of metronidazole susceptibility was 97.1% (95%CI: 0.888-0.995), and the specificity was 100% (95%CI: 0.883-1.000). Cohen's kappa analysis showed substantial agreement, and kappa coefficient was 0.959 (95%CI: 0.902-1.016, P < 0.001). Spearmans correlation analysis confirmed this correlation was significant (r=0.807, P < 0.001). The consistency evaluation of Bland-Altman method indicated that it was good, and there was no measured value outside the consistency interval. In this study, cost analysis, including materials and labor, showed a 32.2% higher cost per analyte for ADM as compared with the E-test (356.6 yuan vs. 269.8 yuan).@*CONCLUSION@#The susceptibility test of H. pylori to metronidazole by E-test presents better agreement with ADM. Because it is less expensive, less labor intensive, and more rapid, it is an easy and reliable method for H. pylori susceptibility testing.

Optimized Concomitant Therapy for the First-line Eradication of Helicobacter pylori Infection / 中国药学杂志

OBJECTIVE: To investigate the efficacy, safety and compliance of optimized concomitant therapy for the first-line eradication of Helicobacter pylori infection through a prospective, single-center and open-label cohort study. METHODS: From January 2014 to October 2018, 200 nafive patients with Helicobacter pylori infection and dyspepsia received 14 d concomitant therapy (esomeprazole 40 mg, amoxicillin 1 000 mg, clarithromycin 500 mg and tinidazole 500 mg, twice daily orally). Safety and compliance were assessed 1-3 days after eradication. The therapeutic outcome was determined by 13C-urea breath test 4-8 weeks after eradication. Some patients underwent strain culture, antibiotic sensitivity testing and CYP2C19 polymorphism assay. RESULTS: The eradication rates of optimized concomitant therapy: intention-to-treat analysis 88.0% (95% confidence interval 83.0%-92.0%), modified intention-to-treat analysis 91.2% (87.0%-94.8%) and per-protocol analysis 93.0% (89.2%-96.2%). 43.1% of patients had adverse reactions, the majority were mild to moderate, and only 3.0% of patients discontinued medication because of intolerance to adverse reactions. Patients with good compliance accounted for 94.4%. Variate analyses showed that poor compliance and clarithromycin resistance were the independent risk factors for eradication failure. CONCLUSION: Optimized concomitant therapy (14 d duration and double dose of esomeprazole) achieved good efficacy, safety and compliance for the first-line eradication of Helicobacter pylori infection.