Clinical Application of the DiversiLab Microbial Typing System Using Repetitive Sequence-Based PCR for Characterization of Helicobacter pylori in Japan

The prevalence of clarithromycin-resistant Helicobacter pylori isolates: a systematic review and meta-analysis

Background

Knowledge of global clarithromycin (CLA)-resistant rates of Helicobacter pylori (H. pylori) is crucial for decision of the most appropriate eradication therapies with good clinical outcomes. Therefore, this review and meta-analysis aimed to evaluate the global prevalence of the CLA resistance in H. pylori to provide some guidance for selecting the first-line antibiotics.

Method

A comprehensive search was performed for relevant literature until April 2021 in PubMed, Embase, and Web of Science databases. Freeman-Tukey double arcsine transformation was performed to estimate the weighted pooled prevalence of resistance.

Results

The meta-analysis included 248 articles. The prevalence of CLA-resistant H. pylori was 27.53% (95% CI [25.41-29.69]). The heterogeneity between reports was significant (I² = 97.80%, P < 0.01). The resistance rate increased from 24.28% in 2010-2017 to 32.14% in 2018-2021 (P < 0.01). Iran, with 38 articles, has the most report. Nevertheless, Switzerland, Portugal, and Israel had the highest resistance rates (67.16%, 48.11%, and 46.12%, respectively). The heterogeneity between the continents and the antimicrobial susceptibility methods also interpreted standard guidelines and breakpoints was insignificant (P > 0.05).

Conclusion

Overall CLA resistance rate was 27.53%, worldwide. The difference in CLA resistance rate among the included studies can be due to several reasons such as differences in antibiotic prescription rates in various geographic areas, use of different breakpoints or inaccurate criteria in performed studies, and the emergence of multidrug-resistant (MDR) strains.

Minimum inhibitory concentrations of commonly used antibiotics against Helicobacter Pylori: A multicenter study in South China

Aim

To determine the minimum inhibitory concentrations (MICs) of commonly used antibiotics against Helicobacter Pylori (H. pylori) in South China and compare their resistance rates by using EUCAST breakpoints and other breakpoints.

Methods

Patients who had not previously received H. pylori treatment in clinical centers in South China were enrolled in this study from 2017 to 2020. Gastric biopsies were obtained for H. pylori culture. The MICs of amoxicillin (AMX), clarithromycin (CLA), metronidazole (MTZ), levofloxacin (LEV), tetracycline (TET) and furazolidone (FZD) were tested by broth microdilution method and assessed by two different breakpoints. ATCC43504 standard strain served as a control.

Results

A total of 208 H. pylori strains were isolated from patients’ biopsy samples. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for H. pylori were 0.0156-256mg/L (MIC₅₀ 0.125mg/L, MIC₉₀ 4mg/L), 0.0156- >256 mg/L (MIC₅₀ 0.0312mg/L, MIC₉₀ 64mg/L), 0.0156- >256mg/L (MIC₅₀ 8mg/L, MIC₉₀ 256mg/L), 0.0156-256mg/L (MIC₅₀ 0.25mg/L, MIC₉₀ 16mg/L), 0.0156-256mg/L (MIC₅₀ 0.0625mg/L, MIC₉₀ 4mg/L), and 0.0156- >256mg/L (MIC₅₀ 0.0312mg/L, MIC₉₀ 2mg/L), respectively. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for ATCC43504 strain were 0.25mg/L, 0.0625mg/L, 64mg/L, 0.5mg/L, 1mg/L and 0.25mg/L, respectively. The resistance rate of FZD was 11.05%. The overall resistance rates according to EUCAST breakpoints and other breakpoints were 57.21% and 14.90% for AMX (p<0.001), 38.94% and 38.94% for CLA (p = 1), 39.42% and 50.96% for MTZ (p<0.001), 12.98% and 10.58% for TET (p = 0.025), 35.10% and 35.10% for LEV (p = 1), respectively.

Conclusions

Our results demonstrate that AMX, FZD, and TET, but not MTZ, CLR or LEV, showed good anti-H. pylori activity in vitro in South China. When different breakpoints were used, similar results were found with CLA, and LEV, but not with AMX, MTZ, or TET.

Vonoprazan-based triple therapy is effective for Helicobacter pylori eradication irrespective of clarithromycin susceptibility

BACKGROUND

Helicobacter pylori causes peptic ulcers and accounts for over 90% of gastric cancers; however, eradication rates have been declining due to antimicrobial resistance. Vonoprazan (VPZ), a potassium-competitive acid blocker, produces rapid and profound gastric acid suppression and has shown promising effects in the improvement of H. pylori eradication rates. The efficacy and safety of VPZ-based triple therapy as a first-line regimen for H. pylori eradication and its relationship with clarithromycin (CAM) susceptibility were evaluated.

METHODS

From May 2015 to September 2017, H. pylori-infected patients who underwent esophagogastroduodenoscopy with CAM susceptibility testing were prospectively enrolled. Patients received a 7-day triple therapy regimen (VAC) of VPZ (20 mg), amoxicillin (750 mg), and CAM (200 mg) twice daily. Eradication rates, demographics, CAM susceptibility, and safety profiles were assessed.

RESULTS

VAC was administered to 146 patients (median age: 63, range: 22-85 years) (60% of whom were females) who underwent CAM susceptibility testing, and 131 patients underwent ¹³C-urea breath testing to evaluate eradication success. The prevalence of CAM resistance was 34.2%. The overall eradication rates of VAC in per protocol (PP) and "intention to treat" (ITT) analyses were 90.8% (n = 131) and 81.5% (n = 146), respectively. In PP analysis for CAM susceptibility, the eradication rates of VAC were comparable between CAM-sensitive (91.6%, n = 83) and CAM-resistant (89.4%, n = 47) strains. The corresponding rates from the ITT analysis were 80.0% (n = 95) and 84.0% (n = 50), respectively. No adverse events requiring discontinuation of VAC were observed.

CONCLUSIONS

CAM-resistant H. pylori was prevalent in one-third of patients in the Tokyo metropolitan area. VPZ-based triple therapy was highly effective and well-tolerated irrespective of CAM susceptibility. Therefore, it could be a valuable first-line treatment regimen for H. pylori infection.

Using circular RNA hsa_circ_0000190 as a new biomarker in the diagnosis of gastric cancer

BACKGROUND

Circular RNAs (circRNA) are an abundant class of non-coding RNAs in mammalian cells. However, their value in the diagnosis of cancers remains unknown. In this study, we focused on hsa_circ_0000190, which was found to be down-regulated in gastric cancer tissues in our previous microarray screening.

PATIENTS AND METHODS

The hsa_circ_0000190 levels in 104 paired gastric cancer tissues and adjacent non-tumor tissues, 104 plasma samples from patients with gastric cancer and 104 plasma samples from health controls were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Then, the association between the expression level of hsa_circ_0000190 and the clinicopathological features of patients with gastric cancer was further analyzed. A receiver operating characteristic (ROC) curve was generated to evaluate the diagnostic value.

RESULTS

Hsa_circ_0000190 was first found to be down-regulated in gastric cancer tissues (P<0.001) and plasma samples from patients with gastric cancer (P<0.001). Its expression levels were significantly correlated with tumor diameter (P=0.034), lymphatic metastasis (P=0.026), distal metastasis (P=0.001), TNM stage (P=0.001), and CA19-9 levels (P=0.019). The areas under the ROC curve (AUC) of hsa_circ_0000190 in tissues and plasma were up to 0.75 and 0.60, respectively. The sensitivity and specificity of the combination were 0.712 and 0.750; the AUC was increased to 0.775.

CONCLUSIONS

These results indicated that hsa_circ_0000190 may be a novel non-invasive biomarker for the diagnosis of gastric cancer. Its AUC, sensitivity and specificity are better than commonly used biomarkers such as CEA and CA19-9.

Prevalence of antibiotic resistance in Helicobacter pylori: A recent literature review

AIM: To review previous studies (the last 6 years) about the Helicobacter pylori (H. pylori) antibiotic resistance in order to evaluate the trend in antibiotic resistance.

METHODS: In this study, the PubMed, MEDLINE, Science Direct, Google Scholar and Scielo manuscripts were reviewed from 2009 to 2014.

RESULTS: On the whole rates of H. pylori antibiotic resistance were 47.22% (30.5%-75.02%) for metronidazole, 19.74% (5.46%-30.8%) for clarithromycin, 18.94% (14.19%-25.28%) for levofloxacin, and 14.67% (2%-40.87%) for amoxicillin, 11.70% (0%-50%) for tetracycline, 11.5% (0%-23%) for furazolidon and 6.75% (1%-12.45%) for rifabutin. The frequency of tetracycline, metronidazole and amoxicillin resistance was higher in Africa, while clarithromycin and levofloxacin resistance was higher in North America and Asian, respectively.

CONCLUSION: The most sensitive drug is rifabutin and the lowest sensitive drug is metronidazole in the world. The worldwide H. pylori antibiotic resistance to clarithromycin and levofloxacin has increased during the last 6 years. The present systematic review show alarming results and a novel plan is needed for eradication therapy of H. pylori infections.