High-Level Primary Clarithromycin Resistance of Helicobacter pylori in Algiers, Algeria: A Prospective Multicenter Molecular Study

Helicobacter pylori Diagnosis and Treatment in Africa: The First Lagos Consensus Statement of the African Helicobacter and Microbiota Study Group

BACKGROUND

Helicobacter pylori (H. pylori) infection is the most prevalent type of bacterial infection. Current guidelines from different regions of the world neglect specific African conditions and requirements. The African Helicobacter and Microbiota Study Group (AHMSG), founded in 2022, aimed to create an Africa-specific consensus report reflecting Africa-specific issues.

SUMMARY

Eighteen experts from nine African countries and two European delegates supported by nine African collaborators from eight other countries prepared statements on the most important African issues in four working groups: (1) epidemiology, (2) diagnosis, (3) indications and prevention, and (4) treatment. Limited resources, restricted access to medical systems, and underdeveloped diagnostic facilities differ from those of other regions. The results of the individual working groups were presented for the final consensus voting, which included all board members.

KEY MESSAGES

There is a need for further studies on H. pylori prevalence in Africa, with diagnosis hinged on specific African situation. Treatment of H. pylori in the African setting should be based on accessibility and reimbursement, while indication and prevention should be defined in specific African countries.

Treatment of Helicobacter pylori infection 14-day concomitant quadruple therapy versus triple therapy: A parallel double-blind randomized controlled trial

Background and Aims

Successful Helicobacter pylori (Hp) eradication with the traditional 7-day course of proton pump inhibitor triple therapy is declining. Prolonging therapy to 14 days is associated with better eradication rates. Most learned societies recommend concomitant quadruple therapy (QC) as a first-line alternative therapy for this bacterial infection. The aim of this study is to compare the efficacy and safety of triple therapy (TT) and QC for the eradication of Hp infection.

Methods

A parallel double-blind randomized controlled trial was conducted. The diagnosis of Hp infection was made by pathological examination of gastric biopsies. Patients were randomly assigned to two treatment groups: either QC (esomeprazole 80 mg, amoxicillin 2000 mg, clarithromycin 1000 mg, and metronidazole 1000 mg daily) or triple therapy (esomeprazole 80 mg, amoxicillin 2000 mg, and clarithromycin 1000 mg daily in divided doses) for 14 days. The efficacy of the treatment is defined by Hp eradication attested by a negative breath test performed 6 weeks after the completion of treatment. Treatment outcomes were compared using the chi-square test, while binary logistic regression identified predictors of treatment failure.

Results

Ninety-two patients were included. Forty-two patients belonged to the QC group and 50 to the TT group. No significant difference was noted between the two groups concerning the rate of Hp eradication either by intention to treat (81% vs. 72% respectively, p = 0.31) or per protocol (81.6% vs. 76.1% respectively, p = 0.54). Likewise, there was no difference between the two groups in terms of tolerance to treatment (59.5% for QC vs. 58% for TT, p = 0.88). No factor has been associated with treatment failure.

Conclusion

There was no significant difference in the rate of HP eradication between the QC and the 14-day triple therapy. Neither regimen should be used topically because of their low eradication rates.

Prevalence of Helicobacter pylori resistance to clarithromycin in Tunisia

Background. Helicobacter pylori (H. pylori) resistance to clarithromycin is increasing worldwide. Data on the prevalence of H. pylori resistance are limited in Tunisia.Gap statement. Given that H. pylori resistance to clarithromycin has not been studied in Tunisia since 2010, there was a need to determinate its prevalence and the principal mutations implicated in this resistance.Aim. The aims were to define the prevalence of H. pylori infection among symptomatic patients and to determinate the level of clarithromycin resistance among these patients and the main mutations conferring this resistance.Methods. We conducted a cross-sectional study from March 2017 to February 2020 in the Hepato-Gastroenterology Department of Hedi Chaker University Hospital in Sfax that included 124 Tunisian patients who underwent gastroduodenal endoscopy with biopsies. Mutations conferring resistance to clarithromycin were detected using the Allplex H. pylori and ClariR PCR Assay.Results. Out of 124 biopsies, 101 (81.5 2 %) were PCR-positive for H. pylori. Mutations conferring resistance to clarithromycin were detected in 30/95 (31.6 %) of patients. The rate of primary resistance was 25.3 % and of secondary resistance 62.5 %. The most frequently detected mutation was A2143G (86, 90%) followed by A2142G (11, 36%). Seven patients had a double mutation A2143G-A2142G. The factors independently associated with resistance to clarithromycin were diabetes, high blood pressure, the presence of a bulbar ulcer on endoscopy and the presence of gastric atrophy on histology.Conclusion. Detection of more than 25 % of strains with clarithromycin resistance mutations makes the H. pylori first-line treatment with clarithromycin questionable in our setting, and a review of empirical treatment of H. pylori is urgently needed.

New Strategy for the Detection and Treatment of Helicobacter pylori Infections in Primary Care Guided by a Non-Invasive PCR in Stool: Protocol of the French HepyPrim Study

Helicobacter pylori (Hp) infects half of the world population and is responsible for gastric, duodenal ulcers and gastric cancer. The eradication of Hp cures ulcers and prevents ulcer recurrences and gastric cancer. Antibiotic resistance of Hp, and particularly clarithromycin resistance, is the primary cause of treatment failure and is a major concern identified by the WHO as a high priority requiring research into new strategies. Treatments guided by the detection of antibiotic resistance have proven their medical and economical superiority. However, this strategy is severely hampered by the invasive nature of the fibroscopy, since antibiotic resistance detection requires gastric biopsies. The eradication of Hp involves primary care physicians. The objective of this study will be to evaluate the feasibility of a strategy for the management of Hp infection in primary care by a recently developed non-invasive procedure and its non-inferiority in eradication rates compared with the strategy recommended by the French National Authority of Health. The non-invasive procedure is a PCR on stool to detect Hp infection and mutations conferring resistance to clarithromycin allowing a treatment guided by the results of the PCR. We present the protocol of a prospective, multicenter, randomized, controlled interventional study in two arms.

Where to Biopsy to Detect Helicobacter pylori and How Many Biopsies Are Needed to Detect Antibiotic Resistance in a Human Stomach

This study aims to determine the gastric distribution, density, and diversity of Helicobacter pylori infection. Subtotal resection of the stomachs of three H. pylori-infected and asymptomatic obese patients were collected after a sleeve gastrectomy. Distribution and density of H. pylori were determined using culture and RT-PCR on multiple gastric sites (88, 176, and 101 biopsies per patient). Diversity of H. pylori strains was studied using antibiotic susceptibility testing, random amplified polymorphism DNA (RAPD) typing and cagA gene detection on single-colony isolates (44, 96, and 49 isolates per patient). H. pylori was detected in nearly all analyzed sites (354/365 biopsies, 97%). Antral density was higher in one patient only. The three stomachs were almost exclusively infected by an antibiotic-susceptible strain. One clarithromycin-resistant isolate in one biopsy was detected in two stomachs (1/44 and 1/49 isolates), while in the third one, eight (8/96 isolates) metronidazole-resistant isolates were detected. DNA typing showed infection with cagA-negative strains for one patient, cagA-positive strains for a second patient and the third patient was infected with two different strains of distinct cagA genotypes. Infection with H. pylori is shown to spread to the whole surface of the stomach, but a possibility of minor sub-population of antibiotic-resistant clones, undetectable in routine practice.

Eradication Treatment of Helicobacter pylori Infection Based on Molecular Pathologic Antibiotic Resistance

Background

Unfortunately, the eradication rate of Helicobacter pylori (H. pylori) treatment is markedly decreasing in recent years and the major reason is antibiotic resistance. Our study was designed to determine the effect and safety of H. pylori eradication treatment based on the molecular pathologic antibiotic resistance.

Methods

261 patients were analyzed retrospectively, including 111 patients who were treated for the first time (one group as First-treated) and 150 patients who failed at least once in bismuth quadruple therapy (another group as Re-treatment). Antibiotic resistance was examined by Real-time PCR detection and conventional PCR and sequencing method. The eradication rate (ER) was compared per intention to treat (ITT) and per protocol (PP) between the two groups.

Results

The resistance rates to amoxicillin, clarithromycin, fluoroquinolone and tetracycline were 5.5%, 42.1%, 41.7% and 12.9% in the 111 first-treated patients, and 11.7%, 79.7%, 70.7% and 30.0% in the 150 re-treatment patients. The ERs in the ITT and PP analyses were 92.79% (95% CI, 87.98–97.60%, n=111) and 98.10% (95% CI, 95.48–100%, n=105), respectively, in the first-treated patients and 90.67% (95% CI, 86.01–95.32%, n=150) and 95.10% (95% CI, 91.57–98.64%, n=143), respectively, in the re-treatment patients. No significant differences were shown in the ERs between two group patients, and no serious adverse events were found.

Conclusion

H. pylori eradication treatment based on molecular pathologic antibiotic resistance showed good effect and safety in both first and re-treated patients.

Infections with Helicobacter pylori and challenges encountered in Africa

Helicobacter pylori (H. pylori) is the causative agent of gastritis, peptic ulcer disease, mucosa associated lymphoid tissue lymphoma and gastric cancer (GC). While this bacterium infects 50% of the world’s population, in Africa its prevalence reach as high as 80% as the infection is acquired during childhood. Risk factors for H. pylori acquisition have been reported to be mainly due to overcrowding, to have infected siblings or parent and to unsafe water sources. Despite this high H. pylori prevalence there still does not exist an African guideline, equivalent to the Maastricht V/Florence Consensus Report of the European Helicobacter and Microbiota Study Group for the management of this infection. In this continent, although there is a paucity of epidemiologic data, a contrast between the high prevalence of H. pylori infection and the low incidence of GC has been reported. This phenomenon is the so-called “African Enigma” and it has been hypothesized that it could be explained by environmental, dietary and genetic factors. A heterogeneity of data both on diagnosis and on therapy have been published. In this context, it is evident that in several African countries the increasing rate of bacterial resistance, mainly to metronidazole and clarithromycin, requires continental guidelines to recommend the appropriate management of H. pylori. The aim of this manuscript is to review current literature on H. pylori infection in Africa, in terms of prevalence, risk factors, impact on human health, treatment and challenges encountered so as to proffer possible solutions to reduce H. pylori transmission in this continent.

The magnitude of antibiotic resistance to Helicobacter pylori in Africa and identified mutations which confer resistance to antibiotics: systematic review and meta-analysis

Background

Worldwide Helicobacter pylori (H.pylori) treatment is of great challenge due to increased antibiotic resistance. The burden of H. pylori antibiotic resistance in Africa is high with unclear information regarding the real magnitude. This systematic review and meta-analysis was conducted to investigate the magnitude of H.pylori antibiotic resistance in Africa to gain insight of the extent of the problem among H.pylori naïve treatment patients.

Method

The search was performed in the academic databases, Embase, PubMed, Web of Science and Africa Wide Information. ProQuest Dissertation and Theses, Scopus, Ethos, Africa Index Medicus (WHO), BioMed Central Proceedings, BASE, British Library, Open grey, Library of Congress and the New York Academy of Grey Literature Report were additionally searched for grey literature. Published articles from Africa on H.pylori antibiotic resistance between 1986 and June 2017 were systematically reviewed to estimate the H. pylori extent of resistance to macrolides, quinolones, amoxicillin, tetracycline and metronidazole.

Results

In 26 articles a total of 2085 isolates were tested for metronidazole, 1530 for amoxicillin, 1277 for tetracycline, 1752 for clarithromycin and 823 for quinolones.The overall pooled proportion of H.pylori resistance to quinolones, clarithromycin, tetracycline, metronidazole and amoxicillin were: (17.4%, 95%CI 12.8 - 21.9), (29.2%, 95%CI:26.7-31.8), (48.7%, 95%CI: 44.5-52.9), (75.8%, 95% CI: 74.1-.77.4) and (72.6%, 95% CI: 68.6-76.6), respectively. The commonest mutation detected were A2143G (49/97) for clarithromycin, RdxA (41/56) for metronidazole and D87I (16/40) for quinolones.

Conclusion

Prevalence of metronidazole, clarithromycin, and amoxicillin resistance is high in developing world including Africa. This could impair the first line triple therapy of the H.pylori infection. There is a need of conducting surveillance of H.pylori susceptibility pattern in Africa for dual and triple resistance which can be used for the empirical treatment.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3099-4) contains supplementary material, which is available to authorized users.

Prevalence, antibiotic resistance, and MLST typing of Helicobacter pylori in Algiers, Algeria

BACKGROUND

Helicobacter pylori infection is common in Algeria, but there are few data on the characterization of isolated strains. The aim of this study was to update data on the prevalence of H. pylori in patients submitted to endoscopy, antibiotic resistance, and phylogeography of H. pylori strains isolated in Algiers.

MATERIALS AND METHODS

This is a prospective study carried out between November 2015 and August 2016. The culture of H. pylori was performed on antral and fundic gastric biopsies of adult patients from 3 hospitals. A real-time PCR using the fluorescence resonance energy transfer (FRET) principle for the detection of H. pylori followed by a melting curve analysis for the detection of mutations associated with resistance to clarithromycin was applied. Differentiation between antral and fundic isolates of the same patient was also determined by RAPD, and an MLST typing was performed for characterization of the phylogeographic group of H. pylori.

RESULTS

By real-time PCR, the prevalence of H. pylori infection among the 147 patients included was 57%. Culture was positive in only 29% of the cases. Twenty-seven percent of patients had received H. pylori eradication treatment. The primary and secondary resistance rates to clarithromycin were 23% and 36%, respectively, and to metronidazole, 45% and 71%, respectively. Only one isolate was resistant to levofloxacin, and no resistance to amoxicillin, tetracycline, and rifampicin was detected. A double population was present in 14 patients. The MLST analysis classified the 42 H. pylori strains from 38 patients in 2 haplotypes: hpEurope (33) and hpNEAfrica (9).

CONCLUSION

The prevalence of H. pylori remains high in Algeria but appears to be decreasing in recent years. High resistance to clarithromycin requires increased monitoring of the evolution of antibiotic resistance and adaptation of eradication therapy.

Treatment of Helicobacter pylori infection 2017

This review summarizes important studies regarding Helicobacter pylori therapy published from April 2016 to April 2017. The main themes that emerge involve studies assessing the efficacy of bismuth and nonbismuth quadruple regimens. While in recent years, much of the emphasis on the use of bismuth has focussed on its utility in a second-line setting, an increasing number of studies this year have shown excellent efficacy in first-line therapy. The efficacy of bismuth as a second-line after sequential and concomitant therapy was particularly noteworthy. Antibiotic resistance was more intensely studied this year than for a long time, and definite trends are presented regarding an increase in resistance, including the fact that clarithromycin resistance in particular is now at a level where the continued use of clarithromycin triple therapy first-line as a mainstream treatment is not recommended. Another exciting trend to emerge this year is the utility of vonoprazan as an alternative to PPI therapy, especially in resistant and difficult-to-treat groups.

Novel and Effective Therapeutic Regimens for Helicobacter pylori in an Era of Increasing Antibiotic Resistance

Helicobacter pylori (H. pylori) is a common gastrointestinal bacterial strain closely associated with the incidence of chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. A current research and clinical challenge is the increased rate of antibiotic resistance in H. pylori, which has led to a decreased H. pylori eradication rate. In this article, we review recent H. pylori infection and reinfection rates and H. pylori resistance to antibiotics, and we discuss the pertinent treatments. A PubMed literature search was performed using the following keywords: Helicobacter pylori, infection, reinfection, antibiotic resistance, bismuth, proton pump inhibitors, vonoprazan, susceptibility, quintuple therapy, dual therapy, and probiotic. The prevalence of H. pylori has remained high in some areas despite the decreasing trend of H. pylori prevalence observed over time. Additionally, the H. pylori reinfection rate has varied in different countries due to socioeconomic and hygienic conditions. Helicobacter pylori monoresistance to clarithromycin, metronidazole or levofloxacin was common in most countries. However, the prevalence of amoxicillin and tetracycline resistance has remained low. Because H. pylori infection and reinfection present serious challenges and because H. pylori resistance to clarithromycin, metronidazole or levofloxacin remains high in most countries, the selection of an efficient regimen to eradicate H. pylori is critical. Currently, bismuth-containing quadruple therapies still achieve high eradication rates. Moreover, susceptibility-based therapies are alternatives because they may avoid the use of unnecessary antibiotics. Novel regimens, e.g., vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, require further studies concerning their efficiency and safety for treating H. pylori.

Helicobacter pylori Primary Antibiotic Resistance in 2015 in Morocco: A Phenotypic and Genotypic Prospective and Multicenter Study

Knowledge of local antibiotic resistance is crucial to adaption of the choice of effective empirical first-line treatment for Helicobacter pylori infection. The aim of this study was to evaluate, for the first time in Morocco, the prevalence of the primary resistance of H. pylori to clarithromycin, metronidazole, amoxicillin, levofloxacin, tetracycline, and rifamycin. We conducted a 1-year prospective study (2015), including 255 Moroccan patients referred for gastro-duodenal endoscopy to two hospitals of Rabat (Morocco) and never previously treated for H. pylori infection. Three gastric biopsies were collected: one for histology, one for culture, and one for molecular detection of H. pylori and the mutations in 23S rRNA genes that confer resistance to clarithromycin. Antimicrobial susceptibility testing was performed on isolated strains by Etest and disk diffusion methods. One hundred seventy-seven patients were infected (69.4%). The prevalence of primary resistances of H. pylori to clarithromycin was 29%, 40% to metronidazole, 0% to amoxicillin, tetracycline, and rifamycin, and 11% to levofloxacin. Only four isolates (2%) were resistant to both clarithromycin and metronidazole. The high level of primary clarithromycin resistance in the H. pylori strains infecting the Moroccan population leads us to recommend the abandonment of the standard clarithromycin-based triple therapy as a first-line treatment in Morocco and to prefer a concomitant quadruple therapy.