Prospective multicentre study on antibiotic resistance of Helicobacter pylori strains obtained from children living in Europe

Antibiotic-Resistant Strains of Helicobacter pylori in 50 Antibiotic Treatment-Naive Children in Northeast Poland Diagnosed by Gastric or Duodenal Biopsy Between February 2019 and May 2022

BACKGROUND In recent years, an increasing prevalence of Helicobacter pylori resistance to antibiotics has been observed. The aim of this study was to assess antibiotic resistance of Helicobacter pylori in previously untreated children from northeast Poland. MATERIAL AND METHODS Inclusion criteria comprised suspicion of Helicobacter pylori infection based on the presence of Helicobacter pylori antigen in the stool and/or characteristic macroscopic lesions seen on esophagogastroduodenoscopy. Samples of the gastric and/or duodenal mucosa were collected from 82 children with a median age of 13 years (range 3-17) during esophagogastroduodenoscopy between February 2019 and May 2022. The material was cultured, and positive Helicobacter pylori strains were tested for drug resistance to amoxicillin, metronidazole, and clarithromycin using the quantitative antibiotic concentration gradient stripe method E-test. RESULTS Based on biopsy culture, Helicobacter pylori infection was confirmed in 50 (61%) children. Helicobacter pylori resistance was most common to clarithromycin (n=19; 38%), followed by metronidazole (n=15; 30%), and the least frequent to amoxicillin (n=13; 26%). The resistance to 1 antibiotic was found in 14 children (28%). Double-drug resistance was noted in 3 children (6%) and triple drug resistance in 9 children (18%). In the whole group, 24 children (48%) were susceptible to all 3 antibiotics. CONCLUSIONS In this study, conducted for the first time in treatment-naïve children in northeast Poland, we found a high proportion of Helicobacter pylori strains resistant to at least 1 antibiotic. Our results may help in the appropriate choice of antibiotics for treatment of Helicobacter pylori in our region.

Helicobacter pylori in children: think before you kill the bug!

Since the discovery of Helicobacter pylori (H. pylori) as the causative organism for gastric and duodenal ulcers four decades ago and subsequent recognition as class 1 gastric carcinogen, countless numbers of studies have been conducted and papers published, on the efficacy of various management strategies to eradicate the infection. In adults, a global consensus by the experts in the field concluded that H. pylori gastritis is an infectious disease and requires treatment irrespective of the presence or absence of symptoms due to the potential for serious complication like peptic ulcer disease and gastric neoplasia. However, although more than half the world's population harbors H. pylori, these serious complications occur only in a small minority of the infected population, even less so in childhood. More importantly, there is accumulating evidence for beneficial role of H. pylori against many chronic health conditions, from several epidemiological and laboratory studies. No doubt, eradication therapy is indicated in children with H. pylori-related peptic ulcer disease. Even though the pediatric guidelines from various learned societies recommend against a "test and treat" strategy, this is not always adhered to. With the accumulating evidence of the possible beneficial role of H. pylori, it is time to pause and think, are we causing more harm than good by eradicating H. pylori in every child who has this bug?

Effects of 14-days bismuth- and tetracycline-containing quadruple therapy with concomitant regimen for the first line Helicobacterpylori eradication

Background

Helicobacter pylori (H. pylori) has infected about 50% of the world's population and it is the main cause for peptic ulcer, gastric adenocarcinoma and even a major cause for gastric MALT lymphoma.

Methods

This study was performed in Mazandaran, Sari, situated in North of Iran. Three-hundred and twenty-eight adult patients with endoscopically approved gastric or duodenal ulcers or erosions and H. pylori infection were randomly divided into 2 groups to receive either 14 days PABT (Pantoprazole 40 mg, Amoxicillin 1 g, Bismuth 425 mg (all twice daily) and Tetracycline 500 mg four times a day) and PACM (Pantoprazole 40 mg, Amoxicillin 1g, Clarithromycin 500 mg, and Metronidazole 500 mg, all twice daily). To evaluate H. pylori eradication, fecal H. pylori antigen test was performed 8 weeks after treatment.

Results

The eradication rates were 94.51% in the PABT and 91.46% in PACM group based on the intention to treat analysis. Moreover, the eradication rates were 95.58% and 92.72% according to per-protocol analysis, respectively. Also, both groups had very low rates of severe side effects.

Conclusion

Regarding the ideal eradication rates achieved by both treatment groups and the low rates of severe side effects, both treatment protocols can be prescribed for H. pylori eradication in North of Iran.

Microbiota in the stomach and application of probiotics to gastroduodenal diseases

The stomach is a hostile environment for most microbes because strong gastric acid kills indigenous microorganisms. Thus, the mass of indigenous microbes detected by traditional culturing method in a highly acidic stomach is reported to be very small. However, in a stomach with less acidity due to atrophic changes of the gastric mucosa, the number of live gastric microbiota dramatically increases and their composition changes. A probiotic is defined as a live microorganism that, when administered in adequate amounts, confers a health benefit on the host. The administration of probiotics to the stomach has thus far been considered impractical, mainly due to the strong acidity in the stomach. The identification of candidate probiotic strains with sufficient resistance to acidity and the ability to achieve close proximity to the gastric mucosa could enable the application of probiotics to the stomach. The utilization of probiotics alone for Helicobacter pylori (H. pylori) infection significantly improves gastric mucosal inflammation and decreases the density of H. pylori on the mucosa, although complete eradication of H. pylori has not yet been demonstrated. The use of probiotics in combination with antimicrobial agents significantly increases the H. pylori eradication rate, especially when the H. pylori strains are resistant to antimicrobial agents. While H. pylori has been considered the most important pathogenic bacterium for the development of gastric cancer, bacteria other than H. pylori are also suggested to be causative pathogens that promote the development of gastric cancer, even after the eradication of H. pylori. Increased non-H. pylori Gram-negative bacteria in the stomach with weak acidity accompanying atrophic gastritis may perpetuate gastric mucosal inflammation and accelerate carcinogenic progression, even after H. pylori eradication. Probiotics restore the acidity in this stomach environment and may therefore prevent the development of gastric cancer by termination of Gram-negative bacteria-induced inflammation. Functional dyspepsia (FD) is defined as the presence of symptoms that are thought to originate in the gastroduodenal region in the absence of any organic, systematic or metabolic diseases. Accumulating evidence has pointed out the duodenum as a target region underlying the pathophysiology of FD. A randomized placebo-controlled clinical trial using a probiotic strain (LG21) demonstrated a significant improving effect on major FD symptoms. One of the possible mechanisms of this effect is protection of the duodenal mucosa from injurious intestinal bacteria through the resolution of small intestinal bacterial over growth.

Management of Helicobacter pylori infection in paediatric patients in Europe: results from the EuroPedHp Registry

Purpose

The EuroPedHp-registry aims to monitor guideline-conform management, antibiotic resistance, and eradication success of 2-week triple therapy tailored to antibiotic susceptibility (TTT) in Helicobacter pylori-infected children.

Methods

From 2017 to 2020, 30 centres from 17 European countries reported anonymized demographic, clinical, antibiotic susceptibility, treatment, and follow-up data. Multivariable logistic regression identified factors associated with treatment failure.

Results

Of 1605 patients, 873 had follow-up data (53.2% female, median age 13.0 years, 7.5% with ulcer), thereof 741 (85%) treatment naïve (group A) and 132 (15%) after failed therapy (group B). Resistance to metronidazole was present in 21% (A: 17.7%, B: 40.2%), clarithromycin in 28.8% (A: 25%, B: 51.4%), and both in 7.1% (A: 3.8%, B: 26.5%). The majority received 2-week tailored triple therapy combining proton pump inhibitor (PPI), amoxicillin with clarithromycin (PAC) or metronidazole (PAM). Dosing was lower than recommended for PPI (A: 49%, B: 41%) and amoxicillin (A: 6%, B: 56%). In treatment naïve patients, eradication reached 90% (n = 503, 95% CI 87–93%) and 93% in compliant children (n = 447, 95% CI 90–95%). Tailored triple therapy cured 59% patients after failed therapy (n = 69, 95% CI 48–71%). Treatment failure was associated with PAM in single clarithromycin resistance (OR = 2.47, 95% CI 1.10–5.53), with PAC in single metronidazole resistance (OR = 3.44, 95% CI 1.47–8.08), and with low compliance (OR = 5.89, 95% CI 2.49–13.95).

Conclusions

Guideline-conform 2-weeks therapy with PPI, amoxicillin, clarithromycin or metronidazole tailored to antibiotic susceptibility achieves primary eradication of ≥ 90%. Higher failure rates in single-resistant strains despite tailored treatment indicate missed resistance by sampling error.

Detection of A2143G, A2142C, and A2142G Point Mutations with Real-Time PCR in Stool Specimens from Children Infected with Helicobacter pylori

Reports have indicated an increasing prevalence of clarithromycin resistance in children relative to adults. Thus, it is important to investigate primary clarithromycin resistance before therapy to avoid treatment failure. A2142G, A2143G, and A2142C point mutations in the peptidyltransferase region of the 23S ribosomal RNA (rRNA) of Helicobacter pylori (H. pylori) strains isolated from children with gastrointestinal symptoms and asymptomatic children were evaluated via real-time polymerase chain reaction (RT-PCR) using fecal DNA samples. The presence of H. pylori was determined using a fecal H. pylori antigen enzyme-linked immunosorbent assay (ELISA) kit from the stools of children (n = 543). A2143G, A2142C, and A2142G point mutations were detected via RT-PCR and confirmed by sequencing the 23S rDNA. Fecal H. pylori antigen testing was positive in 101 symptomatic (49) and asymptomatic (52) children. A significant difference was found between the 0–5- and 5–18-year-old groups in terms of the A2143G and A2142G point mutations (p = 0.001). The A2142C mutation was not detected. There was a significant difference in the A2143G mutation between the symptomatic and asymptomatic 5–18-year-old children (p = 0.019). Macrolides are frequently used to treat upper respiratory tract infections in children due to their selective pressure effect. We suggest that H. pylori strains carrying mutations in the 23S RNA subunit conferring clarithromycin resistance may lead to an intense inflammatory response in the gastric epithelial cells, allowing them to proliferate more rapidly and causing possible diarrhea, halitosis, or abdominal pain in children.

The Challenges of Eradicating Pediatric Helicobacter pylori Infection in the Era of Probiotics

Helicobacter pylori (H. pylori), the most common infection of childhood, results in life-threatening complications during adulthood if left untreated. Most of these complications are related to H. pylori-induced chronic inflammation. The dysbiosis caused by H. pylori is not limited to the gastric microenvironment, but it affects the entire gastrointestinal tract. Eradication of H. pylori has recently become a real challenge for clinicians due to both the persistent increase in antibiotic resistance worldwide and the wide spectrum of side effects associated with the eradication regimens resulting; therefore, there is an urgent need for more effective and less noxious treatment options. Thus, probiotics might be a promising choice in both adults and children with H. pylori infection since their role in improving the eradication rate of this infection has been proved in multiple studies. The positive effects of probiotics might be explained by their abilities to produce antimicrobial compounds and antioxidants, alter local gastric pH, and subsequently decrease H. pylori colonization and adherence to gastric epithelial cells. Nevertheless, if used alone probiotics do not considerably increase the eradication rate.

Experimental design and optimization of a novel dual-release drug delivery system with therapeutic potential against infection with Helicobacter pylori

The objective of this study was to develop clarithromycin-loaded lipid nanocarriers and incorporate them into microcapsules for pH-specific localized release of clarithromycin in the Helicobacter pylori microenvironment in order to obtain a gastro-retentive and pH-sensitive formulation. A Plackett-Burman design was applied to identify the effect of 5 factors on 3 responses. Then, a central composite design was applied to estimate the most important factors leading to the best compromise between lower particle size, polydispersity index and particle size changes. The optimized clarithromycin-loaded nanocapsules were employed to generate microcapsules by different methodologies. Nanocarriers and microcapsules were characterized in vitro. Experimental design and conditions were optimized to obtain nanocapsules of around 100 nm by a modified phase inversion-based process. High particle size homogeneity and high stability were achieved. At 4 °C both optimized lipid nanocapsules were stable during at least 365 days, confirming stability under those conditions. Clarithromycin incorporation in the nanocarrier was effective. Both types of microcoating were evaluated regarding their pH sensitivity. Spray drying microcapsules exhibited similar and uncontrolled release profiles at pH 2 and 7.4. Alternatively, when microcoatings were generated using an Encapsulator, release was insignificant at pH 2, while at pH 7.4 release was triggered, and appeared more appropriate to formulate microcapsules that release nanocarriers under pH neutral Helicobacter pylori microenvironment conditions, thereby permitting effective drug delivery in infected locations. The release of clarithromycin from lipid nanocarrier loaded microcapsules was pH-sensitive suggesting that this could be an effective strategy for clarithromycin delivery to the Helicobacter pylori microenvironment. Clarithromycin nanocapsules with and without microcoating showed a high anti-Helicobacter pylori activity in vitro.

Antibiotic resistances and eradication rates in Helicobacter pylori infection

INTRODUCTION

The resistance to antibiotics of Helicobacter pylori (H. pylori) is the main factor that affects current therapeutic treatments. The main objective of this study is to describe the pattern of antibiotic resistances in children with an infection due to H. pylori.

PATIENTS AND METHODS

An observational, retrospective study was conducted from 2014 to 2019, which included patients between 5 and 17 years old, on whom a gastroscopy, with a gastric biopsy culture positive for H. pylori, and an antibiotic sensitivity study was performed. The antibiotic sensitivity studies were performed using an epsilometer (E-test). The cut-off points to define the resistances were those proposed by the European Committee on Antimicrobial Susceptibility Testing - EUCAST. The eradication study was performed using the 13C-urea breath test or the H. pylori monoclonal test in faeces 6-8 weeks after finalising the treatment.

RESULTS

The study included 80 patients (63.8% females), with a mean age of 11.9 years (SD ± 2.7 DS). Over one-third (38.8%) of the patients had received previous treatment for H. pylori. In the endoscopy, peptic ulcer lesions were observed in 10% of patients. More than two-thirds (67.5%) had resistance to at least one drug. 16.3% presented double resistance. The primary resistances were: clarithromycin, 44.9%, metronidazole 16.3%, levofloxacine 7.9%, and amoxicillin 2%. Patients that received treatment according to the new ESPGHAN 2017 guidelines had significantly higher eradication rates compared to those that received treatment according to previous guidelines (80% vs. 55.8%, P = 0.04).

CONCLUSIONS

The high rate of H. pylori resistances, and as a result, the low eradication rates, are still a very important cause for concern. The first line treatment, when this is indicated must be given following the antibiotic sensitivity studies, and in the cases where these cannot be done or are not available, at least in accordance with the regional resistance rates. The correct application of the new guidelines significantly improves the eradication rate.

Probiotics as the live microscopic fighters against Helicobacter pylori gastric infections

Background

Helicobacter pylori (H. pylori) is the causative agent of stomach diseases such as duodenal ulcer and gastric cancer, in this regard incomplete eradication of this bacterium has become to a serious concern. Probiotics are a group of the beneficial bacteria which increase the cure rate of H. pylori infections through various mechanisms such as competitive inhibition, co-aggregation ability, enhancing mucus production, production of bacteriocins, and modulating immune response.

Result

In this study, according to the received articles, the anti-H. pylori activities of probiotics were reviewed. Based on studies, administration of standard antibiotic therapy combined with probiotics plays an important role in the effective treatment of H. pylori infection. According to the literature, Lactobacillus casei, Lactobacillus reuteri, Lactobacillus rhamnosus GG, and Saccharomyces boulardii can effectively eradicate H. pylori infection. Our results showed that in addition to decrease gastrointestinal symptoms, probiotics can reduce the side effects of antibiotics (especially diarrhea) by altering the intestinal microbiome.

Conclusion

Nevertheless, antagonist activities of probiotics are H. pylori strain-specific. In general, these bacteria can be used for therapeutic purposes such as adjuvant therapy, drug-delivery system, as well as enhancing immune system against H. pylori infection.

[Antibiotic resistances and eradication rates in Helicobacter pylori infection]

INTRODUCTION

The resistance to antibiotics of Helicobacter pylori (H. pylori) is the main factor that affects current therapeutic treatments. The main objective of this study is to describe the pattern of antibiotic resistances in children with an infection due to H. pylori.

PATIENTS AND METHODS

An observational, retrospective study was conducted from 2014 to 2019, which included patients between 5 and 17 years old, on whom a gastroscopy, with a gastric biopsy culture positive for H. pylori, and an antibiotic sensitivity study was performed. The antibiotic sensitivity studies were performed using an epsilometer (E-test). The cut-off points to define the resistances were those proposed by the European Committee on Antimicrobial Susceptibility Testing - EUCAST. The eradication study was performed using the 13C-urea breath test or the H. pylori monoclonal test in faeces 6-8 weeks after finalising the treatment.

RESULTS

The study included 80 patients (63.8% females), with a mean age of 11.9 years (SD±2.7DS). Over one-third (38.8%) of the patients had received previous treatment for H. pylori. In the endoscopy, peptic ulcer lesions were observed in 10% of patients. More than two-thirds (67.5%) had resistance to at least one drug. 16.3% presented double resistance. The primary resistances were: clarithromycin, 44.9%, metronidazole 16.3%, levofloxacine 7.9%, and amoxicillin 2%. Patients that received treatment according to the new ESPGHAN 2017 guidelines had significantly higher eradication rates compared to those that received treatment according to previous guidelines (80% vs. 55.8%, P=.04).

CONCLUSIONS

The high rate of H.pylori resistances, and as a result, the low eradication rates, are still a very important cause for concern. The first line treatment, when this is indicated must be given following the antibiotic sensitivity studies, and in the cases where these cannot be done or are not available, at least in accordance with the regional resistance rates. The correct application of the new guidelines significantly improves the eradication rate.

Efficacy of a novel sequential treatment regimen containing bismuth for Helicobacter pylori eradication in Turkish children

BACKGROUND

Eradication rates of Helicobacter pylori (H pylori) with standard triple therapy are gradually decreasing all over the world, including in children, due to the development of strains resistant to antimicrobials. Sequential therapy can be used as an alternative method to increase eradication rates.

MATERIALS AND METHODS

A total of 75 patients ≥ 8 years of age with H pylori gastritis were included in the study. According to Rome IV criteria, 38 patients had functional abdominal pain and dyspepsia, and 37 patients had alarm findings suggesting organic disease. Patients were treated with a novel sequential therapy consisting of the proton pump inhibitor (PPI)-lansoprazole (1 mg/kg/day, maximum 30 mg daily), amoxicillin (50 mg/kg/d in two doses, maximum 2 × 1000 mg) for 7 days followed by PPI-lansoprazole (1 mg/kg/d, maximum 30 mg daily), metronidazole (20 mg/kg/day in two doses, maximum 2 x 500 mg), tetracycline (50 mg/kg/d divided into four equal doses, maximum 4 x 500 mg), and bismuth subsalicylate (262 mg QID in patients ≤ 10 years of age, 524 mg QID in patients > 10 years of age in days 8-14). Eradication status was evaluated by H pylori stool antigen test 8 weeks after the completion of treatment.

RESULTS

The mean age of the patients was 15.1 ± 2.4 years and 51 (68%) were female. No patient discontinued therapy due to side effects. All patients had antral gastritis (76.0%) or pangastritis (24.0%). The peptic ulcer rate was 6.6%. Eradication therapy was given to all patients with or without peptic ulcer. H pylori eradication was achieved in 69 (92.0%) patients and symptoms improved in 61 of those eradicated.

CONCLUSIONS

As a first-line treatment for H pylori eradication in children, administering a novel sequential therapy including bismuth for 14 days provides a high rate of eradication.

Helicobacter pylori Infection in Pediatric Patients Living in Europe: Results of the EuroPedHP Registry 2013 to 2016

OBJECTIVES

The aim of the study was to assess clinical presentation, endoscopic findings, antibiotic susceptibility and treatment success of Helicobacter pylori (H. pylori) infected pediatric patients.

METHODS

Between 2013 and 2016, 23 pediatric hospitals from 17 countries prospectively submitted data on consecutive H. pylori-infected (culture positive) patients to the EuroPedHP-Registry.

RESULTS

Of 1333 patients recruited (55.1% girls, median age 12.6 years), 1168 (87.6%) were therapy naïve (group A) and 165 (12.4%) had failed treatment (group B). Patients resided in North/Western (29.6%), Southern (34.1%) and Eastern Europe (23.0%), or Israel/Turkey (13.4%). Main indications for endoscopy were abdominal pain or dyspepsia (81.2%, 1078/1328). Antral nodularity was reported in 77.8% (1031/1326) of patients, gastric or duodenal ulcers and erosions in 5.1% and 12.8%, respectively. Primary resistance to clarithromycin (CLA) and metronidazole (MET) occurred in 25% and 21%, respectively, and increased after failed therapy. Bacterial strains were fully susceptible in 60.5% of group A, but in only 27.4% of group B. Primary CLA resistance was higher in Southern and Eastern Europe (adjusted odds ratio [ORadj] = 3.44, 95% confidence interval [CI] 2.22-5.32, P < 0.001 and 2.62, 95% CI: 1.63-4.22, P < 0.001, respectively) compared with Northern/Western Europe. Children born outside Europe showed higher primary MET resistance (ORadj = 3.81, 95% CI: 2.25-6.45, P < 0.001). Treatment success in group A reached only 79.8% (568/712) with 7 to 14 days triple therapy tailored to antibiotic susceptibility.

CONCLUSIONS

Peptic ulcers are rare in dyspeptic H. pylori-infected children. Primary resistance to CLA and MET is markedly dependent on geographical regions of birth and residence. The ongoing survey will show whether implementation of the updated ESPGHAN/NASPGHAN guidelines will improve the eradication success.

Helicobacter pylori: getting to grips with the guidance

Helicobacter pylori is a Gram-negative bacterium that inhabits the mucus layer above the gastric mucosa. While infection rates vary by region, the global prevalence is estimated at 50%. While asymptomatic carriage is common, infection can result in significant morbidity and mortality from complications including peptic ulcer disease, atrophic gastritis and gastric cancer. Paediatric and adult practices diverge due to differences in complication rate, symptomatology, practicalities with investigations and treatment options. Widespread use of standard antibiotic regimens has however resulted in a rapid global increase in antibiotic resistance and treatment failure in all ages. There is urgent need to optimise treatment regimens and maximise first-time eradication rates. This need is reflected in the latest guidelines from the European Society for Paediatric Gastroenterology Hepatology and Nutrition and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition for paediatric practice and the Maastricht Guidelines for adult practice. This article aims to provide a practical overview of the investigations and management of H. pylori by comparing and contrasting these guidelines.

Phenotypic and Genotypic Analysis of Resistant Helicobacter pylori Strains Isolated from Children with Gastrointestinal Diseases

Antibiotic resistance of Helicobacter pylori is currently a global issue. The aim of this study was to analyze actual antibiotic resistance rates of H. pylori strains isolated from children with primary infections and to compare the incidence of mutations that determine resistance to clarithromycin (CH) and metronidazole (MET) in children with different clinical diagnoses. A total of 91 H. pylori strains were isolated from 108 children with primary infections. Drug susceptibility testing of the strains was performed using E-test method. Classical sequencing of DNA fragments was used to detect point mutations for CH and MET resistance. Resistance to CH was detected in 31% of isolated strains (28/91), while resistance to MET and CH was detected in 35% (32/91) of strains. A2143G was the most frequently detected mutation and was dominant among strains isolated from children with peptic ulcer disease (80%). Mutations in the rdxA gene were found significantly more frequently among MET-resistant strains than MET-sensitive strains (p = 0.03, Chi2 = 4.3909). In children, a higher frequency of H. pylori multiresistant strains was observed compared with the previous study in the same area. Differences were found in the occurrence of point mutations among H. pylori strains resistant to CH isolated from children with different clinical diagnoses.

Meta-analysis of the efficacy of probiotic-supplemented therapy on the eradication of H. pylori and incidence of therapy-associated side effects

Traditional therapies for Helicobacter pylori (H. pylori) infection remain hindered by the antibiotic resistance of the pathogen and the poor therapeutic compliance of patients. To address these issues, probiotics have been added as an adjunctive therapy. This meta-analysis aimed to evaluate the efficacy of probiotic supplementation during standard therapy on the eradication rate of H. pylori infection and incidence of therapy-related side effects. Four online databases were searched for eligible studies without language restriction. Review Manager (REVMAN, Version 5.3) was used to perform all data analyses. Forty articles including 5792 patients met our criteria and were included in the analysis. Notably, probiotic supplementation improved the eradication rate by approximately 10% relative to the control group [odds ratio (OR), 1.94, 95% confidence interval (CI): 1.70-2.22, P < 0.00001]. The incidence of total side effects (OR, 0.56, 95% CI: 0.45-0.70, P < 0.00001) and individual symptoms (e.g., diarrhea, vomiting and nausea, constipation, epigastric pain, taste disturbance) also decreased significantly with probiotic supplementation. No other differences in side effects were observed between the experimental and control groups. Moreover, a longer duration (≥10 days) of probiotic treatment had positive effects on both eradication rate of H. pylori and incidence of overall side effects.

Epidemiology, Diagnosis and Risk Factors of Helicobacter pylori Infection

Helicobacter pylori is a human-specific pathogen, which leads to gastric pathologies including gastric cancer. It is a highly unique bacterium considered as a carcinogenic agent. H. pylori remains a major human health problem, responsible for ~90% of the gastric cancer cases. Approximately four billion individuals have been detected for H. pylori infection worldwide in 2015. At the turn of the twenty-first century, the prevalence of H. pylori has been declining in highly industrialized countries of the Western world, whereas prevalence has plateaued at a high level in developing and newly industrialized countries. However, the infection status remains high in immigrants coming from countries with high prevalence of H. pylori infection. H. pylori can be diagnosed both by invasive and non-invasive methods. Urea breath test and stool antigens detection are among the most commonly used non-invasive ones. Although the way H. pylori is transmitted remains still not fully clear, the level of contamination is strongly dependent on the familial and environmental context, with a drastic impact of living conditions with poor hygiene and sanitation. However, familial socioeconomic status is the main risk factor for H. pylori infection among children. In addition, food and water source have a high impact on the prevalence of H. pylori infection worldwide. This chapter highlights the latest knowledge in the epidemiology of H. pylori infection, its diagnosis and critical risk factors responsible for its high prevalence in some populations and geographic areas.

Prevalence of clarithromycin-resistant Helicobacter pylori in children living in South of Sweden: a 12-year follow-up

Objective: The occurrence of Helicobacter pylori (HP) and clarithromycin resistant HP (crHP) have not been investigated longitudinally in the Swedish childhood population. The aims were to study the prevalence of gastric HP-DNA and crHP strains in a cohort of children living in the southernmost parts of Sweden who were investigated with upper endoscopy between 2005 and 2016. Methods: HP colonisation and crHP in 1768 children who underwent 1887 endoscopic procedures with gastric biopsies, of whom 393 were referred for abdominal pain, gastritis, ulcer or gastrointestinal bleeding (Group I) and 1494 were referred for other reasons (Group II). The occurrence of HP-DNA from gastric biopsies was given as a global prevalence as information on previous eradication were missing. Results: The global prevalence of HP-DNA was 222/1887 (11.8%; 95% CI 10.4%-13.3%) of which 46/222 (20.7%; 95% CI 15.9%-26.5%) were crHP. The prevalence of HP-DNA in Group I was 141/393 (35.9%; 95% CI 31.3%-40.7%), which was higher compared with that of 81/1494 (5.4%; 95% CI 4.4%-6.7%) in Group II (p < .0001). crHP strains occurred equally frequent in the biopsies in both groups and found in 29/141 (20.6%; 95% CI 14.7%-28.0%) in Group I and 17/81 (21.0%; 95% CI 13.5%-31.1%) in Group II, respectively (p > .9999). Conclusions: More than one in every ten (12%) children investigated with upper endoscopy in the southernmost parts of Sweden were gastric HP-DNA positive of which 21% were crHP regardless of indication for investigation. Clarithromycin is therefore not recommended as first line empirical treatment for eradicating an HP infection in children.

Helicobacter pylori resistance to clarithromycin and fluoroquinolones in a pediatric population in Turkey: A cross-sectional study

BACKGROUND

Helicobacter pylori antimicrobial resistance is gradually increasing around the world. However, there are a limited number of studies reporting on this issue in the pediatric population. In this study, we aimed to determine H pylori resistance to clarithromycin and fluoroquinolones in the pediatric patients living in Kırıkkale province that were detected with H pylori in gastric biopsies. Moreover, we also aimed to investigate the concordance between the histopathologic and molecular methods used in the diagnosis of H pylori infection.

MATERIALS AND METHODS

Patients aged 2-18 years who had a history of epigastric pain and/or nausea persisting for longer than 1 month underwent upper gastrointestinal endoscopy. Biopsies were taken from the gastric antral mucosa. In the samples detected with H pylori in the histopathologic examination, the presence of H pylori and H pylori resistance to clarithromycin and fluoroquinolones was investigated using the GenoType HelicoDR test which allows the detection of wild-type and mutant genes. The strains detected with more than one mutant gene are defined as hetero-resistant strains.

RESULTS

The 93 patients that underwent DNA extraction and amplification included 68 (73.1%) girls and 25 (26.9%) boys with a median age of 15 ± 2.62 (range 6-17) years. The overall concordance for the diagnosis of H pylori infection between histopathology and PCR was 94%, and H pylori resistance to clarithromycin and fluoroquinolones was 27% and 15%, respectively.

CONCLUSIONS

The high H pylori resistance to clarithromycin and fluoroquinolones among the pediatric patients in our region implicates that the antibiotic sensitivity of strains should be studied prior to administration in accordance with the recommendations provided in the guidelines. Moreover, the presence of hetero-resistant strains in our patients may be a reason for treatment failure.

Adapted first-line treatment of Helicobacter pylori infection in Algerian children

BACKGROUND

Helicobacter pylori (H. pylori) infection is acquired in early life and continues to have a high prevalence, especially in developing countries. Growing antibiotic-resistant strains necessitate adapted treatments. This study aimed to compare the efficacy, side effects, and influence of resistance of H. pylori strains between two different treatments.

METHODS

This prospective, randomized blind study enrolled 112 symptomatic children infected with H. pylori (66 girls, mean age 11.1 years). Treatments, allocated randomly irrespective of the susceptibility of the strains, were either the standard omeprazole-amoxicillin-clarithromycin combination for 7 days (OAC7; group A) or omeprazole-amoxicillin with a higher dose of metronidazole (40 instead of 20 mg/kg/d) for 10 days (OAM10; group B).

RESULTS

Before treatment, the resistance rates of H. pylori strains to metronidazole or clarithromycin were 37% and 13%, respectively, with 7% resistant to both antibiotics and neither to amoxicillin. Eradication rates obtained with OAM10 (80% by intention-to-treat [ITT] and 88% by per protocol [PP] analysis) were higher than with OAC7 (68% in ITT and 71% PP) and the differences (12% in ITT and 17% PP) were statistically significant (P=0.03). Successful treatments with OAM10 were obtained in metronidazole resistant strains and were more effective in children aged >10 years (P=0.02 by ITT and P=0.04 by PP). Only light or moderate side effects, mainly digestive, were observed.

CONCLUSION

Because of its therapeutic efficacy, good tolerance and lower cost the OAM10 can be considered as an appropriate first-line therapeutic scheme in Algeria.

Antimicrobial resistance among Helicobacter pylori isolates in Alaska, 2000-2016

OBJECTIVES

Alaska Natives experience a high burden of Helicobacter pylori infection and concomitant high rates of gastric cancer. Additionally, the prevalence of antimicrobial-resistant H. pylori has been shown to be high in Alaska. In this study, antimicrobial resistance over time among sentinel surveillance isolates was evaluated and risk factors for carrying antimicrobial-resistant H. pylori were assessed.

METHODS

Through Alaska's H. pylori sentinel surveillance system, antral and fundal biopsies from Alaska Native patients undergoing esophagogastroduodenoscopy for clinical indications during 2000-2016 were collected and cultured. For positive cultures, minimum inhibitory concentrations (MICs) of metronidazole, amoxicillin, clarithromycin, tetracycline and levofloxacin were determined.

RESULTS

A total of 800 H. pylori isolates obtained from 763 patients were tested. Resistance to metronidazole was most common (342/800; 42.8%), followed clarithromycin (238/800; 29.8%), both clarithromycin and metronidazole (128/800; 16.0%) and levofloxacin (113/800; 14.1%). Low proportions of isolates were resistant to amoxicillin and tetracycline. Levofloxacin resistance increased between 2000 and 2016 (P<0.001), but resistance to other antimicrobials did not change over time. Metronidazole and clarithromycin resistance were more common among women (P<0.001 for both), whilst levofloxacin resistance was more common among those with an urban residence (P=0.003). Metronidazole and levofloxacin resistance were more common among older patients (P<0.05).

CONCLUSION

Between 2000 and 2016, a large percentage of H. pylori isolates received by the Alaska Sentinel Surveillance System demonstrated resistance to common antimicrobials. The surveillance system provides valuable information for clinicians to make informed treatment choices for patient with H. pylori.

Helicobacter pylori antimicrobial resistance in a pediatric population

BACKGROUND

The increasing prevalence of Helicobacter pylori (H. pylori) antimicrobial resistance, primarily for clarithromycin decreases the success of treatment. The aim of this study is to determine the local pattern of first-line antimicrobials resistance and the eradication rate.

MATERIAL AND METHODS

Prospective cohort study of H. pylori infected patients (positive histological or cultural exams) treated at Centro Materno-Infantil do Norte from January of 2013 to October of 2017. Susceptibility to 4 antibiotics: amoxicilin, metronidazole, clarithromycin, and levofloxacin were analyzed by E-test (phenotypic resistance). The E-test was chosen because it is simple and cost-effective for routine susceptibility testing. Point mutations that confer clarithromycin resistance were surveyed (genotypic resistance). Eradication of H. pylori infection was defined by a negative urea breath test or fecal antigen 6-8 weeks after the end of treatment.

RESULTS

Of a total of 74 H. pylori infected patients, 16 were excluded because they had previous H. pylori treatment or severe systemic disease. Median age of infection cases was 15 years (3-17 years). Eradication regimen used in all patients combined the use of 3 antibiotics (amoxicillin and metronidazole or clarithromycin) and proton pump inibhitor for 14 days and was tailored according antimicrobial susceptibility. 79.5% of the patients completed the treatment. The resistance rate for metronidazole and clarithromycin was 3.3% and 23.3%, respectively. There was no resistance for amoxicilin and levofloxacin. The rate of genotypic resistance to clarithromycin was 37.2%. The eradication rate was 97.8%.

CONCLUSIONS

The authors found a high resistance rate of H. pylori for clarithromycin in this northern portuguese pediatric center. This factor should determine a change in local current treatment, contraindicating the use of clarithromycin as a first-line treatment for H. pylori infection in children. The high eradication rate maybe explained for the eradication treatment tailored according antimicrobial susceptibility.

Helicobacter pylori and its relationship with variations of gut microbiota in asymptomatic children between 6 and 12 years

Objective

To determine the variations in the composition of the intestinal microbiota in asymptomatic children infected with Helicobacter pylori in comparison with children without the infection.

Results

Children infected with H. pylori doubled their probability of presenting 3 of 9 genera of bacteria from the gut microbiota, including: Proteobacteria (p = 0.008), Clostridium (p = 0.040), Firmicutes (p = 0.001) and Prevotella (p = 0.006) in comparison to patients without the infection. We performed a nutritional assessment and found that growth stunting was statistically significantly higher in patients infected with H. pylori (p = 0.046).

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3565-5) contains supplementary material, which is available to authorized users.

Safety of first-line triple therapy with a potassium-competitive acid blocker for Helicobacter pylori eradication in children

BACKGROUND

Helicobacter pylori infection is a risk factor for gastric cancer, and it has been reported that eradication of H. pylori is effective for preventing such cancer. Recently, H. pylori eradication has been performed in children as first-line therapy against gastric cancer. Here, we report use of triple therapy with a potassium-competitive acid blocker (P-CAB) for H. pylori eradication in children.

METHODS

H. pylori infection testing and eradication therapy began in fiscal year 2015 in junior high school students located in Yurihonjo city and Nikaho city, Akita prefecture, Japan. Urine-based immunochromatography, stool antigen enzyme-linked immunosorbent assay tests, and serum antibody tests were performed as the initial screening examination. Those who tested positive on one of the three examinations then underwent a urea breath test (¹³C-UBT). Those who tested positive on ¹³C-UBT and expressed the desire to undergo H. pylori eradication then received eradication therapy comprising 20 mg P-CAB, 750 mg amoxicillin, and 200 mg clarithromycin twice a day for 7 days. At least 8 weeks after treatment, eradication success was evaluated using ¹³C-UBT.

RESULTS

A total of 118 students received eradication therapy. Eradication rates were 81.3% (95% confidence interval: 74.3-88.4, 96/118) in ITT analysis and 85.7% (95% confidence interval: 79.1-92.9 96/112) in PP analysis. Adverse effects associated with eradication therapy were observed in 25 of 118 subjects (21.1%), seven of whom required hospital treatment (rash in five, vomiting in two). All seven subjects either discontinued therapy or were administered anti-allergy drugs, which resulted in swift alleviation of symptoms.

CONCLUSIONS

First-line triple therapy with a P-CAB for H. pylori eradication in children was found to be safe.

Key lime (Citrus aurantifolia) inhibits the growth of triple drug resistant Helicobacter pylori

Background

Eradication rate for Helicobacter pylori (H. pylori) has decreased due to antibiotic resistance. Therefore, new strategies are needed to enhance H. pylori eradication, especially for H. pylori with high antibiotic resistance. The objective of this study was to evaluate anti-H. pylori activities of constituents from key lime (Citrus aurantifolia) and their possible inhibitory effects on urease activity of H. pylori.

Methods

Helicobacter pylori strain ATCC 43526 and triple drug resistant (TDR) H. pylori strains were used in this study. Urease activities of H. pylori strains were measured by ammonia colorimetrical quantification using ELISA reader. Minimum inhibitory concentrations were determined by agar dilution method for antibiotics and by modified media dilution method for each constituent of Citrus aurantifolia (C. aurantifolia).

Results

Citrus aurantifolia extract decreased the number of colonies of H. pylori strain ATCC 43526 and TDR H. pylori stains. An increasing concentration of C. aurantifolia extract attenuated urease activities of H. pylori strain ATCC 43526 and TDR H. pylori strains. Among constituents of C. aurantifolia, citral and 4-hexen-3-one were found to be able to inhibit the growth of H. pylori strain ATCC 43526 and TDR H. pylori strains. Furthermore, citral and 4-hexen-3-one inhibited urease activities of H. pylori strain ATCC 43526 and TDR H. pylori strains in a dose-dependent manner.

Conclusion

Citrus aurantifolia has antimicrobial effect on TDR H. pylori strains, suggesting that C. aurantifolia might have therapeutic potential to control antibiotic-resistant H. pylori strains that cause eradication failure using other antibiotics.

Primary antibiotic resistance and its relationship with cagA and vacA genes in Helicobacter pylori isolates from Algerian patients

The epidemiology of Helicobacter pylori resistance to antibiotics is poorly documented in Africa and especially in Algeria. The aim of our study was to determine the antibiotic resistance rates, as well as its possible relationship with VacA and CagA virulence markers of isolates from Algerian patients. One hundred and fifty one H. pylori isolate were obtained between 2012 and 2015 from 200 patients with upper abdominal pain. Antimicrobial susceptibility testing was performed for amoxicillin, clarithromycin, metronidazole, ciprofloxacin, rifampicin and tetracycline. Molecular identification of H. pylori and the detection of vacA and cagA genes were performed using specific primers. We found that H. pylori was present in 83.5% of collected biopsies, 54.9% of the samples were cagA positive, 49.67% were vacA s1m1, 18.30% were vacA s1m2 and 25.49% were vacA s2m2. Isolates were characterized by no resistance to amoxicillin (0%), tetracycline (0%), rifampicin (0%), a high rate of resistance to metronidazole (61.1%) and a lower rate of resistance to clarithromycin (22.8%) and ciprofloxacin (16.8%). No statically significant relationship was found between vagA and cagA genotypes and antibiotic resistance results (p > 0.5) except for the metronidazole, which had relation with the presence of cagA genotype (p = 0.001).

Construction and optimization of pH-sensitive nanoparticle delivery system containing PLGA and UCCs-2 for targeted treatment of Helicobacter pylori

The acidic environment of the stomach is a threat to the curative effect of antimicrobial drugs for the eradication of Helicobacter pylori (H. pylori) in the infected area. The conventional clinical formulations of antibiotics have low specificity to H. pylori, which disrupts the normal balance of intestinal microbiomes. Therefore, oral drug delivery system with better stability at low pH as well as higher specificity to target H. pylori would provide more effective strategy to eradicate H. pylori and reduce the side effect of antibiotics. Based on the construction of UreI-mediated targeted drug delivery system developed by our group, in this work, using urea-modified UCCs-2 as targeting moiety to the UreI channel protein which is specifically expressed on H. pylori, pH-sensitive amoxicillin-loaded AMX-PLGA/UCCs-2 nanoparticles produced by UCCs-2 and PLGA for targeted treatment of H. pylori infection were established. The nanoparticles were prepared by double emulsion-solvent evaporation method. To achieve a promising drug delivery system with favorable pH-sensitive properties, we adopted an orthogonal design to obtain the optimal formulation. The results showed that the optimized AMX-PLGA/UCCs-2 nanoparticles were in a favorable pH sensitive manner and exhibited low cytotoxicity, higher specificity and better anti-H. pylori efficiency than amoxicillin and non-targeting AMX-PLGA/Cs nanoparticle both in vitro and in vivo, which can protect the antimicrobial drugs against acidic environment and deliver them to targeted eradicate H. pylori in the infected location. The cellular uptake mechanism showed that AMX-PLGA/UCCs-2 nanoparticles are an effective UreI-mediated targeted drug delivery system for anti-H. pylori treatment, which can also be used as promising nanocarriers for oral delivery of other therapeutic drugs to targeted treat H. pylori.

Helicobacter pylori treatment: antibiotics or probiotics

Treatment of Helicobacter pylori infection is important for the management of gastrointestinal disorders such as peptic ulcer and gastric cancer. Due to the increase in the prevalence of H. pylori resistance to antibiotics, triple therapy with clarithromycin is no longer the best treatment for H. pylori, especially in some areas where the local resistance to this antibiotic is higher than 20%. Alternative treatments have been proposed for the eradication of H. pylori. Some of them including novel antibiotics or classical ones in different combinations; these treatments are being used in the regular clinical practice as novel and more effective treatments. Others therapies are using probiotics associated to antibiotics to treat this infection.The present article is a revision of H. pylori eradication treatment, focusing on emerging approaches to avoid the treatment failure, using new therapies with antimicrobials or with probiotics.

Antibacterial resistance and the success of tailored triple therapy in Helicobacter pylori strains isolated from Slovenian children

BACKGROUND

Primary Helicobacter pylori (H. pylori) infection occurs predominantly in childhood. Antimicrobial resistance is the leading cause for H. pylori eradication failure. The aims of this study were (i) to establish for the first time the antimicrobial resistance of H. pylori strains in infected Slovenian children not previously treated for H. pylori infection and (ii) to evaluate the effectiveness of tailored triple therapy, assuming that eradication rate with tailored triple therapy will be >90%.

METHODS

Data on all treatment-naive children 1-18 years old and treated for H. pylori infection according to susceptibility testing were retrospectively analyzed. All relevant clinical information and demographical information were retrospectively collected from the hospital information systems and/or patients' medical documentation.

RESULTS

The inclusion criteria were met by 107 children (64.5% girls) with a median age of 12.0 years (range 2.0-17.6 years). Primary antimicrobial resistance rates of H. pylori were 1.0% to amoxicillin (AMO), 23.4% to clarithromycin (CLA), 20.2% to metronidazole (MET), 2.8% to levofloxacin (LEV), and 0.0% to tetracycline (TET). Dual resistances were detected to CLA and MET in 11.5% (n=12) of strains, to CLA and LEV in 2.8% (n=3), and to MET and LEV in 2.9% (n=3). Results of treatment success were available for 71 patients (66.2% girls). Eradication of H. pylori was evaluated using the 13C-urea breath test, monoclonal stool antigen test or in some cases with repeated upper GI endoscopy with histology and cultivation/molecular tests. Eradication was achieved in 61 of 71 (85.9%) patients.

CONCLUSIONS

The primary resistance rates of H. pylori to CLA and MET in Slovenia are high. Our data strongly support the fact that in countries with high prevalence of resistant H. pylori strains susceptibility testing and tailored therapy is essential.

The impact of host's genetic susceptibility on Helicobacter pylori infection in children

The aim of our study was to investigate the impact of interleukin (IL)-6 190C/T, IL-6 174G/C, IL-6 572G/C, tumor necrosis factor-alpha (TNF-α) 308G/A, and angiotensin-converting enzyme (ACE) I/D gene polymorphisms on Helicobacter pylori (H. pylori) infection in children.A cross-sectional study was performed on 126 children (57 children with H. pylori infection and 69 children without H. pylori infection) aged between 3 and 18 years presenting to a Pediatrics Tertiary Hospital from Romania. Children were assessed clinically, endoscopically, histopathologically, and genetically.In our study, we found that the presence of the CT and CT+TT genotypes of IL-6 190C/T (P < .002 and P = .04), allele G of IL-6 572 G/C polymorphism (P = .01), genotypes GA and AA of TNF-α 308 G/A polymorphism (P = .04, P = .01), and genotype II of ACE I/D polymorphism (P = .02) were associated with H. pylori infection, while the CC genotype of IL-6 174G/C polymorphism was scarcely encountered in children with H. pylori infection [P = .02, odds ratio (OR) = 0.06; 95% confidence interval (95% CI): 0.003-0.128]. Taking under consideration the 4 variant genotypes (IL-6 572G/C, IL-6 190C/T, TNF-α 308G/A, and ACE I/D), we noticed a 2 times higher incidence of H. pylori infection (OR = 6.34; 95% CI: 2.15-25.8).We may consider that the IL-6 190C/T, IL-6 174G/C, IL-6 572G/C, TNF-α 308G/A, and ACE I/D gene polymorphisms may increase the children's susceptibility for acquiring H. pylori infection; therefore, they may contribute to the pathogenesis of H. pylori gastritis.

Increasing metronidazole and rifampicin resistance of Helicobacter pylori isolates obtained from children and adolescents between 2002 and 2015 in southwest Germany

BACKGROUND

Increasing antibiotic resistance has been reported for Helicobacter pylori, but data on the prevalence of antibiotic resistance of H. pylori in pediatric patients and the development of resistance over time are sparse.

METHODS

Data for 610 H. pylori isolates obtained between 2002 and 2015 from gastric biopsies of 582 (mainly treatment-naïve) pediatric patients from southwest Germany were analyzed retrospectively regarding the antibiotic susceptibility determined by Etest and patients' characteristics.

RESULTS

Overall resistance to metronidazole, clarithromycin, and rifampicin was 28.7%, 23.2%, and 13.3%, respectively, while resistance to amoxicillin was rare (0.8%). Simultaneous resistance to metronidazole and clarithromycin was observed for 7.7% of the isolates, and 2.3% were resistant to metronidazole, clarithromycin, and rifampicin. Differences between primary vs secondary resistance existed for metronidazole (24.7% vs 38.8%, P=.01) and clarithromycin (17.2% vs 54.1%, P=.0001). From 2002-2008 to 2009-2015, resistance to metronidazole increased from 20.8% to 34.4% (P=.003) and to rifampicin from 3.9% to 18.8% (P=.0001); this was not associated with increased numbers of patients previously treated for H. pylori infection in the second study period. In contrast, resistance to clarithromycin did not change significantly over time. Resistance was not associated with age, sex, or family origin in Europe.

CONCLUSIONS

The considerable antibiotic resistance of H. pylori isolates argues for standard antibiotic susceptibility testing of H. pylori in pediatric patients prior to the initiation of antibiotic therapy.

Standard triple therapy versus sequential therapy for eradication of Helicobacter pylori in treatment naïve and retreat patients

BACKGROUND AND STUDY AIMS

Untreated Helicobacter pylori infection causes increased risk of gastric cancer, GI morbidity and mortality. Standard treatment for eradication of Helicobacter pylori infection, is the triple therapy which consists of a proton pump inhibitor; together with two antibiotics (amoxicillin 1000mg with clarithromycin 500mg or metronidazole 400mg) given twice daily for 7-14days. Recent evidence revealed, that cure rates of Helicobacter pylori infection with triple therapy had fallen below satisfactory targets. Sequential therapy consisting of a twice daily dose of a PPI for ten days with Amoxicillin given at 1000mg twice daily in the first 5days followed by clarithromycin 500mg and Metronidazole 400mg given twice daily in the subsequent 5days, was recommended to improve eradication rates. We performed a randomised open label study to compare the efficacy of sequential against triple therapy in Helicobacter pylori naive and retreat patients.

PATIENTS AND METHODS

In a randomised open label observational study 485 patients fulfilling inclusion and exclusion criteria were randomly assigned to be treated with triple therapy (n=231) or sequential therapy (n=254). Eradication of Helicobacter pylori was documented with ¹⁴C Urea breath test (UBT) performed 6weeks after the treatment.

RESULTS

The intention-to-treat eradication rate was better in sequential therapy group 84.6% than triple therapy 68% (p<0.001). Eradication rates were significantly higher for treatment naive than retreat patients in triple therapy group (70.5% and 58.3%, respectively, p<0.01). A trend of a better response was observed in eradication rate for treatment naive 88.55% versus retreat 74.6% in sequential therapy group but was not statistically significant (p=0.76). Compliance was similar in the two groups, however side effects were less and the clinical response was better in the sequential therapy group.

Sequential Therapy for Helicobacter pylori Infection in Treatment-naïve Children

The goal of first-line Helicobacter pylori therapy is to reach an eradication rate of 90% to avoid further investigations, antibiotic use, and spreading of resistant strains.

AIM

To evaluate the eradication rate of high-dose sequential therapy in treatment-naïve children and to assess factors associated with failure.

METHODS

Prospective data assessed in a registry from nine European centers between October 2009 and December 2011. Children with biopsy-proven Helicobacter pylori infection were prescribed 5 days of esomeprazole and amoxicillin, followed by 5 days of esomeprazole, clarithromycin, and metronidazole according to bodyweight. Eradication was assessed after 8-12 weeks. Primary endpoint was the eradication rate in children who received at least one dose and had follow-up data. Multivariate analysis evaluated potential factors for treatment success including sex, age, center, migrant status, antibiotic resistance, and adherence to therapy.

RESULTS

Follow-up was available in 209 of 232 patients (age range 3.1-17.9 years, 118 females). Primary resistance occurred for clarithromycin in 30 of 209 (14.4%), for metronidazole in 32 (15.3%), for both antibiotics in 7 (3.3%), and culture failed in 6 (2.9%). Eradication was achieved in 168 of 209 children (80.4%, 95% CI 75.02-85.78), in 85.8% with no resistance, 72.6% with single resistance, and 28.6% with double resistance. Independent factors affecting eradication rate included resistance to clarithromycin (adjusted ORs 0.27 (0.09-0.84), p = .024), to metronidazole (0.25 (0.009-0.72), p = .010) or to both (0.04 (0.01-0.35), p = .004), and intake of ≤ 90% of prescribed drugs (0.03 (0.01-0.18), p < .001).

CONCLUSION

A high-dose 10-day sequential therapy cannot be recommended in treatment-naïve children.

Vaccine against Helicobacter pylori: Inevitable approach

Over three decades have passed since the discovery of Helicobacter pylori (H. pylori), and yet many questions about its treatment remain unanswered. For example, there is no certainty regarding continued use of current antibiotic therapy against H. pylori. The bad news is that even combined regimens are also unable to eradicate bacterial colonization. The worst problem with H. pylori chemotherapy is that even if we identify the most successful regimen, it cannot eliminate the risk of re-infection. This problem is further complicated by the fact that clinicians have no information as to whether probiotics are useful or not. Moreover, to date, we have no large scale produced vaccine effective against H. pylori. Due to the relatively rapid and abundant dissemination of guidelines globally reported concerning management of gastric cancer prevention and therapeutic regimens, clinicians may choose a vaccine as better effective weapon against H. pylori. Therefore, a radical shift in adopted strategies is needed to guide ultimate decisions regarding H. pylori management. In light of failures in vaccine projects, we should identify better vaccine design targeting conserved/essential genes. The unique character and persistence of H. pylori pose obstacles to making an effective vaccine. Preferably, in developing countries, the best reasonable and logical approach is to recommend prophylactic H. pylori vaccine among children as an obligatory national program to limit primary colonization. Trying to produce a therapeutic vaccine would be postponed until later. In reality, we should not forget to prescribe narrow spectrum antibiotics. In the current review, I draw a route to define the best adopted strategy against this rogue bacterium.

Detection of clarithromycin-resistant Helicobacter pylori in clinical specimens by molecular methods: A review

Various molecular methods have been developed to rapidly detect clarithromycin (CLR) resistance in Helicobacter pylori isolates in clinical specimens. All of these assays for detecting CLR resistance in H. pylori are based on detection of mutations in the 23S rRNA gene. In this article, we summarise current knowledge regarding the detection of H. pylori CLR resistance in clinical specimens by molecular tests. The available data showed that restriction fragment length polymorphism (RFLP), 3'-mismatch PCR, DNA sequencing, the PCR line probe assay (PCR-LiPA) and fluorescence in situ hybridisation assay (FISH) are able to detect CLR-resistant H. pylori in clinical specimens with excellent specificity and sensitivity. However, several factors limit their clinical application, including fastidious, time-consuming preparation and low-throughput as well as carrying a risk of contamination. Furthermore, as an invasive method, FISH is not suitable for children or the elderly. Among the molecular methods, one that is most promising for the future is real-time PCR probe hybridisation technology using fluorescence resonance energy transfer (FRET) probes, which can rapidly detect CLR resistance with high sensitivity and specificity in biopsies and stool specimens, even though mixed infections are present in clinical specimens. Moreover, due to the advantages that this method is simple, rapid and economical, real-time PCR is technically feasible for clinical application in small- and medium-sized hospitals in developing countries. Second, with high sensitivity, specificity and throughput, DNA chips will also be a valuable tool for detecting resistant H. pylori isolates from cultures and clinical specimens.

Primary Antibiotic Resistance to Helicobacter pylori Strains Isolated From Children in Northern Iran: A Single Center Study

Background:

Initial resistance to antibiotics is the main reason for the failure of Helicobacter pylori (H. pylori) eradication in children.

Objectives:

As we commonly face high antibiotic resistance rates in children, we aimed to determine the susceptibility of H. pylori to common antibiotics.

Patients and Methods:

In this cross-sectional in vitro study, 169 children younger than 14 years with clinical diagnosis of peptic ulcer underwent upper gastrointestinal endoscopy. Biopsy specimens from stomach and duodenum were cultured. In isolated colonies, tests of catalase, urease, and oxidase as well as gram staining were performed. After confirming the colonies as H. pylori, the antibiogram was obtained using disk diffusion method.

Results:

Culture for H. pylori was positive in 12.3% of the specimens, urease test in 21.3%, serological test in 18.9% and stool antigen test was positive in 21.9%. We could show high specificity but moderate sensitivity of both histological and H. pylori stool antigen tests to detect H. pylori. The overall susceptibility to metronidazole was 42.9%, amoxicillin 95.2%, clarithromycin 85.7%, furazolidone 61.9%, azithromycin 81.0%, and tetracycline 76.2% with the highest resistance to metronidazole and the lowest to clarithromycin.

Conclusions:

In our region, there is high resistance of H. pylori to some antibiotics including metronidazole and furazolidone among affected children. To reduce the prevalence of this antibiotic resistance, more controlled use of antibiotics should be considered in children.

Helicobacter pylori Infection in Children. Antimicrobial Resistance and Treatment Response

BACKGROUND

The aim of this study was to determine the appropriateness of the recent recommendations for managing Helicobacter pylori infection in children in a university hospital in Southern Europe. Antimicrobial resistance and response to eradication therapy were also determined.

MATERIALS AND METHODS

The presence of H. pylori was studied in 143 children: by gastric biopsy culture (GBC), (13)C-urea breath test (UBT) and stool antigen immunochromatography test (SAIT) in 56 children; by GBC and UBT in 20, by GBC and SAIT in 18, and by GBC alone in 49. Antimicrobial susceptibility was determined by E-test. Infection was defined as a positive culture or positivity in both UBT and SAIT. Disease progression was studied in 118 patients. First evaluation of symptoms was carried out at 3-6 months after diagnosis and/or after treatment of the infection.

RESULTS

H. pylori was detected in 74 from the 143 children analyzed (100% GBC positive, 98.1% UBT positive, and 58.1% SAIT positive). The main symptom was chronic abdominal pain (n = 121). Macroscopic antral nodularity was observed in 29.7% of infected patients and in 5.8% of uninfected patients, respectively. Resistance to clarithromycin and metronidazole was found in 34.7 and 16.7%, respectively. Eradication when susceptible antimicrobials were used occurred in 78.7% (48/61) versus 37.5% (3/8) when the treatment included a drug with resistance (p = .024). In patients with recurrent abdominal pain, symptoms resolved in 92.9% (39/42) patients with HP eradication versus 42.9% (6/14) without HP eradication (p < .001).

CONCLUSION

Treated patients often failed to meet the criteria established in the guidelines for H. pylori diagnostic screening and treatment because most of them had only recurrent abdominal pain, but remission of their symptoms was associated with H. pylori eradication.

Advances in the treatment of Helicobacter pylori infection in children

In this review we elaborate on two main questions concerning the management of Helicobacter pylori infection in children. First, we focus on who should be treated. In the presence of Helicobacter pylori (H. pylori)-associated peptic ulcer disease, eradication of the micro-organism is recommended. When H. pylori infection is detected by biopsy-based methods in the absence of peptic ulcer disease in a child with dyspeptic symptoms, treatment of H. pylori infection may be considered. In infected children whose first degree relatives have gastric cancer, treatment can be offered. A 'test-and-treat' strategy is not and has never been recommended in children. The second issue to address is what the recommended treatments are. ESPGHAN/NASPGHAN recommends that treatment tailored to susceptibility testing should be the first choice in pediatric patients. The duration of therapy should be 10-14 days. Costs, compliance and adverse effects should be taken into account. Checking the result of eradication with a reliable non-invasive test such as the 13C urea breath test, is recommended at least 4-8 weeks following completion of therapy.

New Diagnostic Strategies for Detection of Helicobacter pylori Infection in Pediatric Patients

Helicobacter pylori (H pylori) is a common chronic bacterial infection that is an important cause of peptic ulcer disease and gastroduodenal disease in children. H pylori is also associated with extragastric manifestations, including growth reduction, iron-deficiency anemia, and idiopathic thrombocytopenic purpura. Current guidelines recommend endoscopy with biopsy for the definitive demonstration of H pylori infection. In contrast to serology, the fecal antigen test and the urea breath test provide reliable, sensitive, and specific results for detecting active H pylori infection in children before and after treatment. The first-line treatment option for pediatric patients is triple therapy with a proton pump inhibitor and 2 antibiotics, which include amoxicillin and clarithromycin or metronidazole. Decreasing eradication rates and the emergence of antibiotic-resistant strains of H pylori have led to the use of other treatments, such as sequential therapy or triple therapy with newer antibiotics, particularly in geographic areas with high rates of antibiotic resistance. Patients should be tested after treatment to confirm eradication, as the absence of symptoms does not necessarily mean that H pylori is no longer present. This clinical roundtable monograph provides an overview of H pylori infection, as well as expert insight into the diagnosis and management of H pylori infection in children.

Trends in secondary antibiotic resistance of Helicobacter pylori from 2007 to 2014: has the tide turned? J Clin Microbiol. 2015;53:522-527. [PMID: 25428158 DOI: 10.1128/jcm.03001-14]

The current guidelines recommend culture and antibiotic susceptibility testing of Helicobacter pylori following two failed eradication attempts. Where testing is unavailable, epidemiological data for secondary H. pylori resistance are essential to allow for the rational use of antibiotics. The aim of this study was to describe the temporal changes in antibiotic resistance among adults previously treated for H. pylori infections and to identify predictors of resistance. Between 2007 and 2014, consecutive patients undergoing gastroscopy with H. pylori culture and susceptibility testing at our institution following at least two treatment failures were retrospectively identified. Antibiotic susceptibilities were recorded and linked to the demographic data. A total of 1,042 patients were identified, including 739 (70.9%) males, aged 39.3 ± 18.9 years. Resistance to clarithromycin, metronidazole, and levofloxacin was found in 57.2%, 64.4%, and 5.1% of isolates, respectively. Dual resistance to clarithromycin and metronidazole was seen in 39.9%. Over the study period, clarithromycin resistance increased annually in a linear manner (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.03 to 1.14; P < 0.01), levofloxacin resistance decreased annually (OR, 0.78; 95% CI, 0.61 to 0.92; P < 0.01), and metronidazole resistance was nonlinear. Age was an independent predictor of resistance to all antibiotics. Time elapsed predicted resistance for clarithromycin and levofloxacin and dual resistance for clarithromycin-metronidazole. Secondary resistance of H. pylori to clarithromycin and metronidazole remains high. The low secondary resistance to levofloxacin makes it an attractive treatment option in our region for patients following two failed eradication attempts.

Sequential therapy versus standard triple therapy for Helicobacter pylori eradication in children: any advantage in clarithromycin-resistant strains?

OBJECTIVE

There has been a marked decrease in the eradication rates of Helicobacter pylori infection with standard triple therapy worldwide. Hence, sequential therapy has gained attention as a promising treatment during the last few years. This study was carried out to compare the efficacy of sequential versus standard triple therapy in the context of clarithromycin (CLA) resistance.

MATERIALS AND METHODS

In this study, children between 3 and 18 years of age, who had documented H. pylori infection, were randomized to receive either standard triple or sequential therapy. H. pylori eradication was ascertained using the C-urea breath test 4-6 weeks after the completion of the treatment. Real-time PCR was performed on gastric biopsy samples for assessment of CLA resistance.

RESULTS

In all, 148 children (median age: 12.18±3.51 years) were recruited randomly into the study. The intention-to-treat eradication rates were 50% (37/74) for the sequential treatment group and 52.7% (39/74) for the standard triple treatment group (P=0.87). A total of 136 children completed the study. The per-protocol eradication rates were 56% (37/66) and 55.7% (39/70) for sequential and standard triple therapy groups, respectively. CLA resistance was assessed and 113 children were included in the final analysis. Of 113 participants, 53 were in the sequential treatment group and 60 were in the standard triple treatment group. The success rates of the respective therapies (29/53=54.7% in sequential, 33/60=55% in standard therapy) were similar (P=0.98). CLA resistance was detected in 29 (25.7%) of the patients. Eradication rates with sequential therapy in CLA susceptible and resistant cases were 60.5% (23/38) and 40% (6/15), respectively (P=0.23). The corresponding figures for the standard triple treatment group were 63% (29/46) and 28.6% (4/14) (P=0.033). Although a higher eradication rate was observed in CLA-resistant cases with sequential therapy, the difference did not reach statistical significance (P=0.69).

CONCLUSION

In this study, standard triple treatment failed to eradicate H. pylori infection in the majority of the children, and sequential therapy offered only a small advantage over standard triple therapy in the eradication of CLA-resistant strains.

Prevalence of multiple drug-resistant Helicobacter pylori strains among patients with different gastric disorders in Iran

Emergence of multidrug-resistant (MDR) strains of Helicobacter pylori is a global health concern. This study was aimed to determine the frequency of MDR H. pylori strains in Iran. H. pylori isolates were obtained from cultured gastric biopsy samples on selective culture media after their characterization by PCR and conventional biochemical methods. The minimal inhibitory concentrations of rifampicin, ciprofloxacin, levofloxacin, ampicillin, clarithromycin, erythromycin, metronidazole, and tetracycline were determined for 111 strains that were isolated from 197 dyspeptic patients by the agar dilution method. The primary resistance rates were 61.3% (68/111) for metronidazole, 15.3% (17/111) for ampicillin, and 14.4% (16/111) for rifampicin. Resistance rates for other antimicrobials were as follows: macrolides (erythromycin or clarithromycin) 32.4% (36/111) and quinolones (levofloxacin or ciprofloxacin) 30.6% (34/111). Among the resistant strains, the rates of double and multiple drug resistance phenotypes were 22.6% (19/84) and 34.5% (29/84), respectively. The quadruple drug resistance phenotype encompasses 37.9% of the MDR strains, of which 90% of them was resistant to metronidazole. In conclusion, these results showed a high frequency of MDR phenotypes among the studied H. pylori strains in Iran. The eradication of the H. pylori strains presenting high resistance rates to macrolides, fluoroquinolones, or metronidazole could be achieved by approved tetracycline- or amoxicillin-containing regimens as alternative regimens to standard triple therapy.

Ten-year trend of the cumulative Helicobacter pylori eradication rate for the 'Japanese eradication strategy'

BACKGROUND/AIMS

In Japan, a systematic eradication strategy for Helicobacter pylori has been constructed, and consists of a proton pump inhibitor/amoxicillin and clarithromycin (PPI/AC) therapy as the first-line regimen and proton pump inhibitor/amoxicillin and metronidazole (PPI/AM) therapy as the second-line regimen. The cumulative rate of H. pylori eradication has not been reported. Therefore, we investigated the annual and cumulative eradication rate to verify the efficacy of the 'Japanese eradication strategy'.

METHODS

Patients who received first-line PPI/AC therapy and, if necessary, second-line PPI/AM therapy between 2000 and 2009 were retrospectively analyzed. The annual cumulative eradication rate was calculated. Data were subjected to intention-to-treat analysis.

RESULTS

PPI/AC was administered to 1973 patients (male n = 1,162, female n = 811; mean age: 55.8 years, range: 15–87), and 250 patients received PPI/ AM. The eradication rate for the PPI/AC regimen was 65.3%, and it gradually but significantly decreased over 10 years (p < 0.05). For the PPI/AM regimen, the eradication rate was 84.0%, with no change in the annual eradication rate. The cumulative eradication rates were 76.0% in intention-to-treat analysis and 98.4% in per-protocol analysis, respectively, which provided a consistent annual eradication rate without decreases in effectiveness.

CONCLUSION

Although the eradication rate for the first-line PPI/AC regimen decreased over time, the 'Japanese eradication strategy' provided a sufficient eradication rate.

A cross sectional study on antibiotic resistance pattern of Salmonella typhi clinical isolates from Bangladesh

OBJECTIVE

To investigate and compare the resistance and sensitivity of Salmonella typhi samples to commonly used antibiotics in three major divisions of Bangladesh and to evaluate the gradually developing resistance pattern.

METHODS

The antibiotic susceptibility of 70 clinical isolates collected from blood, sputum, urine and pus samples were identified by specific antisera and with standard biochemical tests. The patients were divided into 5 age groups. Susceptibility and resistance was also tested by Kirby-Bauer disc diffusion method using 12 regularly used antibiotics.

RESULTS

Antibiotic susceptibility test demonstrated that 64.28% isolates of Salmonella typhi were multidrug resistant. Present study suggests that the clinical samples were mostly resistant against nalidixic acid with all age groups and in all three divisions with similar resistance pattern. Resistance is more common among adult people (30-40 years) and children (0-10 years). Salmonella typhi was mostly sensitive against gentamycin, chloramphenicol and ciprofloxacin.

CONCLUSIONS

Although the population density of Dhaka region is markedly higher than Rajshahi and Chittagong regions, no significant difference in resistance pattern was found. The rate of multidrug resistance is a matter of concern. Physicians should reconsider before prescribing nalidixic acid and cefixime. Further molecular study is needed to reveal the genomic and proteomic basis of resistance.