Treatment of Helicobacter pylori

In vitro anti-bactrical activity and its preliminary mechanism of action of the non-medicinal parts of Sanguisorba officinalis L. against Helicobacter pylori infection

ETHNOPHARMACOLOGICAL RELEVANCE

Sanguisorba officinalis L. (S. officinalis L.), known as Di Yu (DY) in Traditional Chinese Medicine (TCM), are used to treat burns, vomiting of blood, asthma, intestinal infections, and dermatitis. It has been reported that the root of DY has a significant inhibitory effect on Helicobacter pylori (H. pylori). However, there is currently little research on the composition analysis and anti-H. pylori infection properties of the non-medicinal parts of DY, such as its stems, leaves, and flowers.

AIM OF STUDY

The commonly used eradication therapies for H. pylori infection are antibiotic-based therapies. With the increasing antibiotic resistance of H. pylori, it is urgent to find effective alternative therapies. To find alternative therapies and increase the utilization of DY, this study aims to investigate the phytochemistry profile, in vitro anti-H. pylori activity, and preliminary antibacterial mechanism of the non-medicinal parts of DY.

MATERIALS AND METHODS

The non-medicinal parts of DY extracts were obtained by using hot water reflux method. The chemical composition of these extracts was analyzed using colorimetric method, high-performance liquid chromatography (HPLC), and ultra-high-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS). The in vitro anti-H. pylori activity was investigated using broth microdilution method, checkerboard dilution method, time-kill curve, time-inhibition curve, scanning electron microscopy, and transmission electron microscopy. Transcriptional sequencing technology was used to study the effect of DY stems and flowers on the gene expression of H. pylori and explore possible antibacterial mechanisms.

RESULTS

The non-medicinal parts of DY contain abundant phytochemicals, such as total phenols and total flavonoids, and possess strong inhibitory and bactericidal activity against both standard and clinical strains of H. pylori in vitro. The MIC was 80-1280 μg/mL and the MBC was 80-2560 μg/mL, and the strength of the antibacterial effects was dependent on the concentration of phytochemicals (total polyphenols, gallic acid and ellagic acid). In addition, the combination of non-medicinal parts of DY with antibiotics, such as amoxicillin, metronidazole, levofloxacin, and clarithromycin, did not result in any antagonistic effects. All of them could disrupt the morphology, internal microscopic and cell wall structures of H. pylori thereby acting as an inhibitor. The mechanism of action was found to be the disruption of H. pylori morphology, internal microstructure, and cell wall. Transcriptomic analysis showed that the non-medicinal parts of DY significantly regulated the gene expression of H. pylori, especially the metabolic pathway.

CONCLUSIONS

This study analyzed the chemical composition of the non-medicinal parts of DY and confirmed its inhibitory and bactericidal activities against H. pylori, both standard and clinical strains. Additional, the mechanism of inhibition involves disrupting the structure of H. pylori cells, altering gene expression, and interfering with bacterial metabolic pathways. This study provides a reference for further resource utilization and the development of H. pylori drugs using the non-medicinal parts of DY.

Helicobacter pylori Dormant States Are Affected by Vitamin C

Helicobacter pylori colonizes human gastric mucosa, overcoming stressful conditions and entering in a dormant state. This study evaluated: (i) H. pylori's physiological changes from active to viable-but-non-culturable (VBNC) and persister (AP) states, establishing times/conditions; (ii) the ability of vitamin C to interfere with dormancy generation/resuscitation. A dormant state was induced in clinical MDR H. pylori 10A/13 by: nutrient starvation (for VBNC generation), incubating in an unenriched medium (Brucella broth) or saline solution (SS), and (for AP generation) treatment with 10xMIC amoxicillin (AMX). The samples were monitored after 24, 48, and 72 h, 8-14 days by OD₆₀₀, CFUs/mL, Live/Dead staining, and an MTT viability test. Afterwards, vitamin C was added to the H. pylori suspension before/after the generation of dormant states, and monitoring took place at 24, 48, and 72 h. The VBNC state was generated after 8 days in SS, and the AP state in AMX for 48 h. Vitamin C reduced its entry into a VBNC state. In AP cells, Vitamin C delayed entry, decreasing viable coccal cells and increasing bacillary/U-shaped bacteria. Vitamin C increased resuscitation (60%) in the VBNC state and reduced the aggregates of the AP state. Vitamin C reduced the incidence of dormant states, promoting the resuscitation rate. Pretreatment with Vitamin C could favor the selection of microbial vegetative forms that are more susceptible to H. pylori therapeutical schemes.

Current and Future Perspectives in the Diagnosis and Management of Helicobacter pylori Infection

Helicobacter pylori (Hp) is a prevalent organism infecting almost half the global population. It is a significant concern, given its associated risk of gastric cancer, which is the third leading cause of cancer death globally. Infection can be asymptomatic or present with dyspeptic symptoms. It may also present with alarm symptoms in the case of progression to cancer. Diagnosis can be achieved non-invasively (breath tests, stool studies, or serology) or invasively (rapid urease test, biopsy, or culture). Treatment involves acid suppression and regimens containing several antibiotics and is guided by resistance rates. Eradication is essential, as it lowers the risk of complications and progression to cancer. Follow-up after eradication is similarly important, as the risk of cancer progression remains. There have been many recent advances in both diagnosis and treatment of Hp. In particular, biosensors may be effective diagnostic tools, and nanotechnology, vaccines, and potassium-competitive acid blockers may prove effective in enhancing eradication rates.

Preparation and Characterization of Controlled-Release Floating Bilayer Tablets of Esomeprazole and Clarithromycin

Controlled-release effervescent floating bilayer tablets reduce dosage frequency and improve patient compliance with enhanced therapeutic outcomes. Generally, two different tablets of clarithromycin and esomeprazole, respectively, are given for the treatment of Helicobacter pylori infection and it might be worth incorporating both in a single tablet. In the current study, controlled-release floating bilayer tablets of clarithromycin and esomeprazole (F1−F4) were developed with different rates of polymeric materials by a direct compression method. During the formulation, Fourier-transform infrared spectroscopy (FTIR) analysis was performed for possible interactions between drugs and excipients. No interactions between drugs and excipients were noted. Moreover, the bilayer tablets’ thickness, diameter, friability, hardness, weight variation, dissolution, and percent purity were found within the acceptable limits. The floating lag time and total floating time of all formulations were found to be < 25 s and 24 h, respectively. The release of both the clarithromycin and esomeprazole started at the same time from the controlled-release floating bilayer tablets by anomalous non-Fickian diffusion, and the polymeric materials extended the drug release rate up to 24 h. In the case of F1, the results approached ideal zero-order kinetics. The dissolution profiles of the tested and reference tablet formulations were compared, but no significant differences were observed. It can be concluded that such controlled-release effervescent floating bilayer tablets can be efficiently used in clinical practice to reduce dosage frequency and increase patient compliance with continuous drug release for 24 h, which ultimately might enhance therapeutic efficacy.

Evidence-based Guidelines for the Treatment of Helicobacter pylori Infection in Korea: 2020 Revised Edition

Helicobacter pylori (H. pylori) infection is one of the most common infectious diseases worldwide. Although its incidence is gradually decreasing, about half of the world's population still get infected. H. pylori infection is responsible for substantial gastrointestinal morbidity worldwide. It is the most common cause of gastric and duodenal ulcers as well as gastric cancer. Since the revision of the H. pylori Clinical Practice Guidelines in 2013, the eradication rate of H. pylori has gradually decreased with the use of classical triple therapy, wherein amoxicillin, clarithromycin, and proton pump inhibitors are administered, for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was due to increased antimicrobial resistance induced by the use of antibiotics, especially clarithromycin. The update of clinical practice guideline for treatment of H. pylori was developed based on evidence-based medicine by conducting a meta-analysis. The draft recommendations were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines are designed to provide patients, nurses, medical school students, policymakers, and clinicians with clinical evidence to guide primary care and treatment of H. pylori infection. These may differ from current medical insurance standards and will be revised further, if necessary, based on research-based evidence.

Helicobacter pylori: Perturbation and restoration of gut microbiome

Alternate remedies with natural products provides unlimited opportunities for new drug development. These can be either as pure compounds or as standardized set of compounds. The phytochemicals and secondary metabolites are in great demand for screening bioactive compounds and plays an important role towards drug development. Natural products have many advantages over to synthetic chemical drugs. Helicobacter pylori (H. pylori) a Gram-negative bacteria has been classified as Class I carcinogen by World Health Organization in 1994. Current treatment regimens for H. pylori is ‘triple therapy’ administrated for two weeks which includes a combination of two antibiotics like Amoxicillin and Clarithromycin and a proton pump inhibitor (PPI) like Lansoprazole, and for ‘quadruple therapy’ in addition to antibiotics and a PPI, Bismuth is used. Antibiotic resistance can be named as the main factor for failure of treatment of H. pylori infection. The need of the hour is to develop a herbal remedy that could combat the growth of H. pylori. Probiotics can also be used as ‘feasible’ tool for H. pylori infection management. Present review is an attempt to briefly discuss about the pathogenicity, genetic predisposition, perturbation of gut microbiota due to antibiotic treatment and restoration of healthy gut microbiota with phytochemicals and probiotics.

Prevalence of Primary Antimicrobial Resistance of H. pylori in Turkey: A Systematic Review

BACKGROUND

The prevalence of clarithromycin resistance has increased to the 20% or more in different regions of the world. Clarithromycin resistance is known to be responsible for most of the treatment failures in Helicobacter pylori (H. pylori) infection. The aim of this systematic review was to summarize the prevalence of primary antibiotic resistance (amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline) of H. pylori strains in different geographical regions of Turkey.

MATERIAL AND METHODS

An Internet search was performed using PubMed and the ULAKBIM Turkish Medical Database. The terms "primary antibiotic resistance (separately; amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline) of H. pylori" with and without "Turkey" or "different geographical regions of Turkey" were searched among articles published in both English and Turkish language within the time span from 1999 to 2015. Data analysis was performed using MedCalc 12.7.0. Each article was weighted according to the number of isolated H. pylori strains. Pooled proportion analysis was performed.

RESULTS

Twenty-one Turkish studies including 1059 H. pylori strains were included in this review. The overall primary antibiotic resistance rates of H. pylori strains isolated in Turkey were as follows: amoxicillin 3 (0.971%), clarithromycin 425 (24.864%), metronidazole 75 (33.747%), tetracycline 2 (3.511%), and levofloxacin 31 (23.769%).

CONCLUSIONS

Primary antibiotic resistance against H. pylori in Turkey shows differences between geographical regions and population densities. There is an increase in primary resistance rates to clarithromycin and metronidazole in different years. The data are not sufficient for tetracycline, amoxicillin, and levofloxacin. High clarithromycin resistance rates were mostly detected in overpopulated cities like Ankara (north), Izmir (west), Istanbul (west), and Bursa (west).

Challenges to the Treatment and New Perspectives for the Eradication of Helicobacter pylori

Helicobacter pylori (H. pylori) is one of the leading causes of gastric diseases such as chronic gastritis, peptic ulcer, and gastric adenocarcinoma. The current treatment of H. pylori infection with antibiotics and proton pump inhibitors has several limitations, including poor adherence and intrinsic patient-related factors, drug resistance, and the absence of adequate treatments. This review summarizes the current therapeutic approaches to eradicating H. pylori, the difficulties associated with its treatment, and several new perspectives aimed at improving existing treatment strategies.

Antimicrobial activity of natural products against Helicobacter pylori: a review

Throughout the genetic and physiological evolution of microorganisms, the microbiological sciences have been expanding the introduction of new therapeutic trials against microbial diseases. Special attention has been paid to the bacterium Helicobacter pylori, which induces gastric infections capable of causing damage, ranging from acute and chronic gastritis to the development of gastric cancer and death. The use of compounds with natural origins has gained popularity in scientific research focused on drug innovation against H. pylori because of their broad flexibility and low toxicity. The aim of this study was to describe the use of natural products against H. pylori in order to clarify important parameters for related fields. The study demonstrated the vast therapeutic possibilities for compounds originating from natural sources and revealed the need for innovations from future investigations to expand the therapeutic arsenal in the fight against H. pylori infection.

Virulence factors and antibiotic resistance in children with Helicobacter pylori gastritis

OBJECTIVES

There are limited data regarding the pattern of Helicobacter pylori (Hp) antibiotic resistance and virulence factors in children. Evaluation of prevalence of drug resistance and virulence-factor genotype in children with Hp gastritis and to investigate whether there is any relation between drug resistance and genotype were our aims in this study.

METHODS

Ninety-eight children with polymerase chain reaction-positive Hp gastritis were included. Antimicrobial susceptibility was tested by disc diffusion method and polymerase chain reaction assays were used for the determination of virulence factors.

RESULTS

The resistance rates to clarithromycin, metronidazole, and amoxicillin were 23.5%, 11.7%, and 3.9%, respectively. All strains carried vacA genotype, and 51%, 70.4%, 49%, 34.7%, and 25.5% were cagA-, cagE-, babA2-, iceA1-, and iceA2-positive, respectively. Of those 98 specimens, 81.6%, 19.4%, 38.8%, and 63.3% carried vacAs1, vacAs2, vacAm1, and vacAm2, respectively. Dominant vacA type was s1am2 (32.7%), followed by s1am1 (14.3%) and s2m2 (12.2%). Significant rates of clarithromycin resistance were observed in cagE-, iceA1-, babA2-, and vacAs1c-positive groups. In those with metronidazole resistance, vacAs1 and vacAs1c were more common (P < 0.05).

CONCLUSIONS

The cagE-positive and vacA s1a/m2 genotypes, which are correlated with increased antibiotic resistance, were predominant in our population. In countries where Hp infection is prevalent, studies focusing on virulence factors and antibiotic susceptibility may provide anticipation of the prognosis and may be helpful to reduce morbidity and mortality.

Synthesis and biological evaluation of novel benzyl piperazine derivatives of 5-(5-nitroaryl)-1,3,4-thiadiazoles as Anti-Helicobacter pylori agents

BACKGROUND AND THE PURPOSE OF THE STUDY

Helicobacter pylori is recognized as the main cause of gastritis and gastroduodenal ulcers and classified as class 1 carcinogen pathogen. Different 1,3,4-thiadiazole derivatives bearing 5-nitroaryl moiety have been shown considerable anti- H. pylori activity. In attempt to find new and potent derivatives of described scaffold, a new series of 1-(substituted benzyl)-4-(5-(5-nitroaryl-2-yl)-1,3,4-thiadiazol-2-yl)piperazine derivatives were synthesized and evaluated against three metronidazole-resistant isolates of H. pylori using paper disk diffusion bioassay test.

METHODS

The title compounds were prepared through the reaction of 1-(5-(5-nitroaryl-2-yl)-1,3,4-thiadiazol-2-yl) piperazine 5a-b and substituted benzyl chloride in DMF. The inhibitory activity of the new derivatives 6a-q against three metronidazole-resistant isolates of H. pylori was evaluated by the disc diffusion method and compared with the commercially available standard drug metronidazole.

RESULTS AND DISCUSSION

The results of SAR study indicated that the potency and anti-H. pylori activity profile of synthesized derivatives is mainly attributed to the substituted nitroaryl moiety at the C-5 position of 1,3,4-thiadiazole ring. Most of 1,3,4-thiadiazole derivatives bearing 5-nitrofuran moiety at C-5 position of central thiadiazole ring, demonstrated more promising anti-H. pylori than the 5-nitrothiophen counterpart.

CONCLUSION

The most potent nitrofuran derivative containing 3-methoxybenzyl piperazine pendant at the C-2 position of 1,3,4-thiadiazole ring (compound 6i), demonstrated strong anti-H. pylori potential at studied concentrations 100-25 μg/disk (IZD > 20 mm) against all studied metronidazole- resistant isolates of H. pylori.

Standard triple versus levofloxacin based regimen for eradication of Helicobacter pylori

AIM

To compare the eradication rates for Helicobacter pylori (H. pylori) and ulcer recurrence of standard triple therapy (STT) and levofloxacin based therapy (LBT).

METHODS

Seventy-four patients with perforated duodenal ulcer treated with simple closure and found to be H. pylori infected on 3 mo follow up were randomized to receive either the STT group comprising of amoxicillin 1 g bid, clarithromycin 500 mg bid and omeprazole 20 mg bid or the LBT group comprising of amoxicillin 1 g bid, levofloxacin 500 mg bid and omeprazole 20 mg bid for 10 d each. The H. pylori eradication rates, side effects, compliance and the recurrence of ulcer were assessed in the two groups at 3 mo follow up.

RESULTS

Thirty-four patients in the STT group and 32 patients in the levofloxacin group presented at 3 mo follow up. H. pylori eradication rates were similar with STT and the LBT groups on intention-to-treat (ITT) analysis (69% vs 80%, P = 0.425) and (79% vs 87%, P = 0.513) by per-protocol (PP) analysis respectively. Ulcer recurrence in the STT and LBT groups on ITT analysis was (20% vs 14%, P = 0.551) and (9% vs 6%, P = 1.00) by PP analysis. Compliance and side effects were also comparable between the groups. A complete course of STT costs Indian Rupees (INR) 1060.00, while LBT costs only INR 360.00.

CONCLUSION

H. pylori eradication rates and the rate of ulcer recurrence were similar between the STT and LBT. The LBT is a more economical option compared to STT.

Standard triple versus levofloxacin based regimen for eradication of Helicobacter pylori

AIM

To compare the eradication rates for Helicobacter pylori (H. pylori) and ulcer recurrence of standard triple therapy (STT) and levofloxacin based therapy (LBT).

METHODS

Seventy-four patients with perforated duodenal ulcer treated with simple closure and found to be H. pylori infected on 3 mo follow up were randomized to receive either the STT group comprising of amoxicillin 1 g bid, clarithromycin 500 mg bid and omeprazole 20 mg bid or the LBT group comprising of amoxicillin 1 g bid, levofloxacin 500 mg bid and omeprazole 20 mg bid for 10 d each. The H. pylori eradication rates, side effects, compliance and the recurrence of ulcer were assessed in the two groups at 3 mo follow up.

RESULTS

Thirty-four patients in the STT group and 32 patients in the levofloxacin group presented at 3 mo follow up. H. pylori eradication rates were similar with STT and the LBT groups on intention-to-treat (ITT) analysis (69% vs 80%, P = 0.425) and (79% vs 87%, P = 0.513) by per-protocol (PP) analysis respectively. Ulcer recurrence in the STT and LBT groups on ITT analysis was (20% vs 14%, P = 0.551) and (9% vs 6%, P = 1.00) by PP analysis. Compliance and side effects were also comparable between the groups. A complete course of STT costs Indian Rupees (INR) 1060.00, while LBT costs only INR 360.00.

CONCLUSION

H. pylori eradication rates and the rate of ulcer recurrence were similar between the STT and LBT. The LBT is a more economical option compared to STT.

Helicobacter pylori eradication therapy: A review of current trends

Helicobacter pylori has been implicated in the formation of chronic gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue lymphoma and gastric cancer. Eradication of H. Pylori has been recommended as treatment and prevention for these complications. This review is based on a search of Medline, the Cochrane Database of Systemic Reviews, and citation lists of relevant publications. Subject heading and key words used include H. Pylori, current treatment and emerging therapy. Only articles in English were included. There has been a substantial decline in the H. pylori eradication rates over the years, despite the use of proton pump inhibitor and bismuth salts for triple and quadruple therapies respectively. The reasons for eradication failure are diverse, among them, antibiotic resistance is an important factor in the treatment failure. Primary resistance to clarithromycin or metronidazole significantly affects the efficacy of eradication therapy. This has led to the introduction of second line, third line "rescue," and sequential therapies for resistant cases. Subsequently, new antibiotic combinations with proton-pump inhibitors and bismuth salts are being studied in the last decade, to find out the antibiotics that are capable of increasing the eradication rates. Some of these antibiotics include Levofloxacin, Doxycycline, Rifaximin, Rifampicin, Furazolidone based therapies. Studies are ongoing to determine the efficacy of Lactoferrin based therapy.

Effects of CYP2C19 loss-of-function variants on the eradication of H. pylori infection in patients treated with proton pump inhibitor-based triple therapy regimens: a meta-analysis of randomized clinical trials

Background

There are inconsistent conclusions about whether CYP2C19 variants could affect H. pylori eradication rate in patients treated with the proton pump inhibitor (PPI)-based therapy. We therefore performed a meta-analysis of randomized clinical trials (RCTs) to re-evaluate the impact of CYP2C19 variants on PPI-based triple therapy for the above indication.

Methods

All relevant RCTs in the PubMed, Cochrane Library, EMBASE, Web of Science and two Chinese databases (up to February 2013) were systematically searched, and a pooled analysis was performed with the odds ratio (OR) and 95% confidence interval (CI) by the STATA software.

Results

Sixteen RCT datasets derived from 3680 patients were included. There was no significant heterogeneity across the data available in this meta-analysis. There were significant differences in that rate between homozygous (HomEMs) and heterozygous (HetEMs) extensive metabolizers (OR 0.724; 95% CI 0.594–0.881), between HomEMs and poor metabolizers (PM) (OR 0.507; 95%CI 0.379–0.679), or between HetEMs and PMs (OR 0.688; 95%CI 0.515–0.920), regardless of the PPI being taken. Furthermore, sub-analysis of individual PPIs was carried out to explore the difference across all the PPIs used. A significantly low rate was seen in HomEMs vs. HetEMs taking either omeprazole (OR 0.329; 95%CI 0.195–0.553) or lansoprazole (OR 0.692; 95%CI 0.485–0.988), and also in HomEMs vs. PMs for omeprazole (OR 0.232; 95%CI 0.105–0.515) or lansoprazole (OR 0.441; 95%CI 0.252–0.771). However, there was no significant difference between HetEMs and PMs taking either one. No significant differences were observed for rabeprazole or esomeprazole across the CYP2C19 genotypes of interest.

Conclusions

Carriage of CYP2C19 loss-of-function variants is associated with increased H. pylori eradication rate in patients taking PPI-based triple therapies when omeprazole or lansoprazole is chosen. However, there is no a class effect after use of rabeprazole or esomeprazole.

In vitro anti-Helicobacter pylori activity of a flavonoid rich extract of Glycyrrhiza glabra and its probable mechanisms of action

ETHNOPHARMACOLOGICAL RELEVANCE

Glycyrrhiza glabra Linn. is regarded useful for peptic ulcer in traditional systems of medicine in India and Helicobacter pylori has been considered as one of the causative factors for peptic ulcer. Aim of the present study is to evaluate the anti-Helicobacter pylori action of GutGard(®), a flavonoid rich extract of Glycyrrhiza glabra and further to elucidate the possible mechanisms of its anti-Helicobacter pylori action.

MATERIALS AND METHODS

Agar dilution and microbroth dilution methods were used to determine the minimum inhibitory concentration of GutGard(®) against Helicobacter pylori. Protein synthesis, DNA gyrase, dihydrofolate reductase assays and anti-adhesion assay in human gastric mucosal cell line were performed to understand the mechanisms of anti-Helicobacter pylori activity of GutGard(®).

RESULTS

GutGard(®) exhibited anti-Helicobacter pylori activity in both agar dilution and microbroth dilution methods. Glabridin, the major flavonoid present in GutGard(®) exhibited superior activity against Helicobacter pylori while glycyrrhizin did not show activity even at 250 μg/ml concentration. In protein synthesis assay, GutGard(®) showed a significant time dependent inhibition as witnessed by the reduction in (35)S methionine incorporation into Helicobacter pylori ATCC 700392 strain. Additionally, GutGard(®) showed a potent inhibitory effect on DNA gyrase and dihydrofolate reductase with IC(50) value of 4.40 μg/ml and 3.33 μg/ml respectively. However, the extract did not show significant inhibition on the adhesion of Helicobacter pylori to human gastric mucosal cell line at the tested concentrations.

CONCLUSION

The present study shows that, GutGard(®) acts against Helicobacter pylori possibly by inhibiting protein synthesis, DNA gyrase and dihydrofolate reductase.

Levofloxacin/amoxicillin-based schemes vs quadruple therapy for Helicobacter pylori eradication in second-line

Worldwide prevalence of Helicobacter pylori (H. pylori) infection is approximately 50%, with the highest being in developing countries. We compared cure rates and tolerability (SE) of second-line anti-H. pylori levofloxacin/amoxicillin (LA)-based triple regimens vs standard quadruple therapy (QT). An English language literature search was performed up to October 2010. A meta-analysis was performed including randomized clinical trials comparing 7- or 10-d LA with 7-d QT. In total, 10 articles and four abstracts were identified. Overall eradication rate in LA was 76.5% (95% CI: 64.4%-97.6%). When only 7-d regimens were included, cure rate was 70.6% (95% CI: 40.2%-99.1%), whereas for 10-d combinations, cure rate was significantly higher (88.7%; 95% CI: 56.1%-109.9%; P < 0.05). Main eradication rate for QT was 67.4% (95% CI: 49.7%-67.9%). The 7-d LA and QT showed comparable efficacy [odds ratio (OR): 1.09; 95% CI: 0.63-1.87], whereas the 10-d LA regimen was significantly more effective than QT (OR: 5.05; 95% CI: 2.74-9.31; P < 0.001; I² = 75%). No differences were reported in QT eradication rates among Asian and European studies, whereas LA regimens were more effective in European populations (78.3% vs 67.7%; P = 0.05). Incidence of SE was lower in LA therapy than QT (OR: 0.39; 95% CI: 0.18-0.85; P = 0.02). A higher rate of side effects was reported in Asian patients who received QT. Our findings support the use of 10-d LA as a simple second-line treatment for H. pylori eradication with an excellent eradication rate and tolerability. The optimal second-line alternative scheme might differ among countries depending on quinolone resistance.

Helicobacter pylori infection in clinical practice: probiotics and a combination of probiotics + lactoferrin improve compliance, but not eradication, in sequential therapy

BACKGROUND

Sequential therapy (ST) seems to offer higher success rates than triple therapy (TT) in the eradication of Helicobacter pylori (H. pylori) infection. However, from the standpoint of therapeutic compliance, there is no difference between the two treatments. Adjuvant treatment (especially with probiotics (PB) and lactoferrin (LF)) has often improved compliance and eradication rates in patients subjected to TT, while ST had never been used in association with adjuvants.

METHODS

Over a period of 2 years, we randomized and divided 227 consecutive adult patients with H. pylori infection into three groups. The patients were given ST with the addition of adjuvants, as follows: group A (ST + placebo), group B (ST + LF + PB), and group C (ST + PB). Our goal was to assess therapeutic compliance, so we prepared a questionnaire to help determine the severity of the side effects. We also determined the eradication rates for the groups.

RESULTS

Patients with ST + placebo had the worst compliance as compared with the other two groups in terms of the absence of symptoms (p < .001 between B and A; p = .001 between C and A) and the presence of intolerable symptoms (p = .016 between B and A; p = .046 between C and A). The differences between the values for the treated groups and those for the placebo group were statistically significant. On the other hand, there was no statistically significant difference in compliance between groups B and C. The eradication rate was similar for the three groups.

CONCLUSIONS

Probiotics associated with ST provide optimum therapeutic compliance compared with the placebo and, despite the need to take a larger number of tablets, they should be taken into consideration as an adjuvant to therapy for H. pylori infection. The addition of LF to the PB did not bring about any further improvements in compliance. As compared with the placebo, the eradication rate of ST did not improve by adding LF + PB or by using PB alone.

Helicobacter pylori infection: sequential therapy followed by levofloxacin-containing triple therapy provides a good cumulative eradication rate

BACKGROUND

In the eradication of H. pylori infection, even today, the main international guidelines recommend the triple therapy as first-line regimen, although its effectiveness is clearly decreasing. As second-line treatment, the bismuth-containing quadruple therapy is the most used regimen, although several other therapies are studied. The Italian guidelines recommend, alternatively, sequential therapy or triple therapy as first-line treatment and levofloxacin-containing triple therapy as second-line regimen. We wanted to assess the overall eradication rate of Helicobacter pylori infection in two therapeutic rounds following the Italian guidelines in clinical practice.

MATERIALS AND METHODS

We treated 231 consecutive Helicobacter pylori-positive patients by sequential therapy and we verified the eradication 8-10 weeks after treatment by stool antigen test. Patients positive for stool antigen test received levofloxacin-containing triple therapy, as second-line therapy, according to Italian Guidelines and they were again submitted to the fecal test 8-10 weeks after the end of treatment.

RESULTS

In the first-line regimen, we obtained an eradication rate of 92.6%, in the second-line of 75.0% and as cumulative result we achieved a 97.8% of eradication, in per-protocol analysis.

CONCLUSIONS

Sequential therapy as first-line and levofloxacin-containing triple therapy as second-line represent a good combination to eradicate Helicobacter pylori infection in only two rounds.

Impact of Lactobacillus reuteri Supplementation on Anti-Helicobacter pylori Levofloxacin-Based Second-Line Therapy. Gastroenterol Res Pract. 2012;2012:740381. [PMID: 22690211 PMCID: PMC3368352 DOI: 10.1155/2012/740381]

Introduction. Helicobacter pylori eradication therapy has the potential burden of antibiotic-associated gastrointestinal (GI) side effects. The occurrence of side effects is among the major drawbacks of such regimens. GI manifestations may be related to alterations in the intestinal microflora. Probiotics can prevent or reduce antibiotic-associated side effects and have an inhibitory effect on H. pylori. Methods. To define the efficacy of Lactobacillus reuteri supplementation in H. pylori eradication and in preventing GI-associated side effects during a second-line levofloxacin triple therapy. 90 H. pylori-positive patients receive for 7 days a second-line triple therapy with esomeprazole, levofloxacin, and amoxicillin with L. reuteri for 14 days (group 1) and without probiotic supplementation (group 2). Each subject received a validated questionnaire to record symptoms everyday for 4 weeks from the start of therapy. H. pylori status and side effects were assessed 6 weeks after treatment. Results. The eradication rate was significantly influenced by probiotic supplementation with L. reuteri (group 1: 36/45, 80%; group 2: 28/45 62%; P < 0.05). The incidence of nausea and diarrhoea in group 1 was significantly lower than that in group 2. Conclusion. In H. pylori-positive subjects L. reuteri supplementation increases the eradication rate while reducing the incidence of the most common side effects associated with antibiotic therapy in second-line treatment.

The status of antimicrobial resistance of Helicobacter pylori in Eastern Azerbaijan, Iran: comparative study according to demographics

Helicobacter pylori-associated infections are extremely common in Iran, but few data about antibiotic sensitivity of H. pylori are available for this region. The purpose of this study was to investigate the prevalence of resistance in isolates against commonly used antibiotics in Eastern Azerbaijan, Iran, and the dependence of prevalence on the sex and age of patients. H. pylori isolates were collected by culture from gastric biopsies. Antibiotic susceptibility of isolates was determined by use of the disk agar diffusion test, and the minimum inhibitory concentration of clarithromycin was established by use of the Etest. A total 395 of biopsy specimens were studied; 112 samples of H. pylori were isolated (28.3 %), 55 (49 %) from males and 57 (51 %) from females. The prevalence of resistance to clarithromycin, metronidazole, erythromycin, amoxicillin, ciprofloxacin, rifampin, nitrofurantoin, and tetracycline were 16 (14.3 %), 86 (76.8 %), 29 (26.0 %), 32 (28.6 %), 37 (33.0 %), 32 (28.6 %), 13 (11.6 %), and 21 (18.7 %), respectively. Antimicrobial resistance was not statistically significantly associated with sex or age. Furthermore, the prevalence of resistance to metronidazole was high and that to clarithromycin was reasonable, consistent with reported low success in H. pylori treatment in this area. Therefore, continuous surveillance of antibiotic resistance of H. pylori is essential.

Immunological response to parenteral vaccination with recombinant hepatitis B virus surface antigen virus-like particles expressing Helicobacter pylori KatA epitopes in a murine H. pylori challenge model

Virus-like particles (VLPs) based on the small envelope protein of hepatitis B virus (HBsAg-S) are immunogenic at the B- and T-cell level. In this study, we inserted overlapping sequences encoding the carboxy terminus of the Helicobacter pylori katA gene product into HBsAg-S. The HBsAg-S-KatA fusion proteins were able to assemble into secretion-competent VLPs (VLP-KatA). The VLP-KatA proteins were able to induce KatA-specific antibodies in immunized mice. The mean total IgG antibody titers 41 days post-primary immunization with VLP-KatA (2.3 × 10(3)) were significantly greater (P < 0.05) than those observed for vaccination with VLP alone (5.2 × 10(2)). Measurement of IgG isotypes revealed responses to both IgG1 and IgG2a (mean titers, 9.0 × 10(4) and 2.6 × 10(4), respectively), with the IgG2a response to vaccination with VLP-KatA being significantly higher than that for mice immunized with KatA alone (P < 0.05). Following challenge of mice with H. pylori, a significantly reduced bacterial load in the gastric mucosa was observed (P < 0.05). This is the first report describing the use of VLPs as a delivery vehicle for H. pylori antigens.

Kefir improves the efficacy and tolerability of triple therapy in eradicating Helicobacter pylori

Preliminary evidence has suggested that probiotics may improve eradication rates in patients infected with Helicobacter pylori treated by triple therapy. This study examined the effect of combining triple therapy with kefir, a fermented milk drink containing probiotics. A randomized, double-blind study was carried out on 82 consecutive patients with symptoms of dyspepsia and H. pylori infection confirmed by the urea breath test. Patients were given a two times a day, 14-day course of lansoprazole (30 mg), amoxicillin (1,000 mg), and clarithromycin (500 mg) with either 250 mL of kefir twice daily (triple therapy + kefir, n = 46) or 250 mL of milk containing placebo (triple therapy + placebo, n = 36). Side effects were determined using a standard questionnaire form at 15 days after beginning treatment. Patients returned for urea breath tests 45 days after beginning treatment. Significantly more triple therapy + kefir patients achieved eradication (36 of 46 [78.2%]) compared with triple therapy + placebo patients (18 of 36 [50.0%]) (P = .026, χ(2) test). Side effects were significantly less frequent and less severe in triple therapy + kefir patients than in triple therapy + placebo patients. We conclude that a 14-day regimen of triple therapy with kefir is more effective in achieving H. pylori eradication than is triple therapy alone.

Recent trends in primary antimicrobial resistance of Helicobacter pylori in Finland

The antimicrobial susceptibility of Helicobacter pylori is an important predictor of the success of eradication therapy. To evaluate recent changes in primary antimicrobial resistance of H. pylori isolated from Finnish patients, the clinical records of H. pylori-positive patients referred for endoscopy to Herttoniemi Hospital (Helsinki, Finland) during 2000-2008 were investigated retrospectively. Stored H. pylori strains from 505 patients without previous eradication therapy were tested for clarithromycin, metronidazole, levofloxacin, tetracycline and amoxicillin susceptibility by Etest. Data on local consumption of antimicrobials were collected and correlations between consumption and resistance were calculated. During the 9-year study period, metronidazole resistance was high (range 29-59%, overall 41%). After an initial increase in clarithromycin resistance (0% in 2000 to 16% in 2003), resistance to clarithromycin decreased to 4% in 2008. No significant correlation was detected between consumption of macrolides and resistance of clarithromycin. Resistance to levofloxacin varied between 0% and 12%. Primary metronidazole resistance in H. pylori is at a high level, however levofloxacin and clarithromycin resistances are still at a reasonable level. Thus, primary clarithromycin resistance in H. pylori in Finland has not become such a problem as in many other countries. Primary resistance to the antimicrobials studied varied considerably from year to year.

The efficacy of Helicobacter pylori eradication regimen with and without vitamin C supplementation

BACKGROUND

Vitamin C in gastric juice and in vitro has been shown to inhibit the growth of Helicobacter pylori (H. pylori).

AIMS

The purpose of this study was to investigate the effect of addition of vitamin C to eradication regimen on H. pylori eradication rate.

PATIENTS

This randomised controlled clinical trial was conducted on 312 patients with H. pylori infection who had referred to the Taleghani Research Center of Gastroenterology and Liver Disease.

METHODS

Patients were randomly divided into two groups. Group A patients (162 patients) received amoxicillin 1g and metronidazole 500 mg b.i.d., bismuth 240 mg b.i.d. and omeprazole 40 mg q.i.d. in two divided doses. Patients in group B (150 patients) received the same regimen plus 500 mg vitamin C per day. All patients received therapy for 2 weeks. Four weeks later all patients underwent urea breath test and results were compared.

RESULTS

A total of 140 patients in group A and 141 in group B completed the study. On intention-to-treat analysis 48.8% of patients in group A in comparison to 78% in group B responded to eradication therapy and had negative urea breath test (p<0.0001).

CONCLUSION

Addition of vitamin C to H. pylori treatment regimen of amoxicillin, metronidazole and bismuth can significantly increases H. pylori eradication rate.

Second-line levofloxacin-based triple schemes for Helicobacter pylori eradication

BACKGROUND

The recommended second-line therapy for Helicobacter pylori (H. pylori) eradication is a quadruple regimen that fails in up to 30% of patients. Several recent studies suggest levofloxacin-based triple therapies as an alternative rescue treatment. However, dosage and length of levofloxacin-based regimens have not been established.

AIM

To compare the efficacy and tolerability of four second-line levofloxacin-based schemes for H. pylori eradication.

METHODS

One hundred and sixty patients (aged 18-70 years, 72 male patients) who were H. pylori positive after standard triple therapies were randomised to receive esomeprazole 20mg b.d. and amoxicillin 1g b.d. plus levofloxacin 500 mg o.d., for 7 or 10 days (Groups A and B) or levofloxacin 500 mg b.d. for 7 days or 10 days (Groups C and D). H. pylori status was assessed by 13-C Urea Breath Test or rapid urease test, before and 6 weeks after therapy. Incidence of side effects was evaluated by a questionnaire.

RESULTS

No dropouts were observed. Eradication of H. pylori infection was successful in: 65% of patients in Group A; 90% in Group B; 70% in Group C; 85% in Group D. Based upon duration of treatment, eradication rates were: 67.5% in 7 days groups and 87.5% in 10 days groups (p=0.004). Dosage of levofloxacin did not affect the eradication rates (77.5% both in the once daily and twice daily groups). Mild adverse events were reported overall in 16% of patients (22.5% in 7 days groups; 27.5% in 10 days groups; p=0.58; 12% in the once daily group; 32.5% in the twice daily group; p=0.04).

CONCLUSIONS

10 days levofloxacin-based second-line regimens were effective in curing H. pylori infection in more than 85% of patients with a lower incidence of adverse effects in levofloxacin single-dosage scheme. The 10 days levofloxacin-based regimens were more effective than 7 days course of treatment showing that duration of therapy is the crucial factor affecting eradication rate.

Meta-analysis: efficacy of bovine lactoferrin in Helicobacter pylori eradication

BACKGROUND

Several randomized-controlled trials (RCTs) have sought to determine the efficacy of bovine lactoferrin in Helicobacter pylori eradication with equivocal results.

AIM

To evaluate the effect of bovine lactoferrin supplementation in H. pylori eradication.

METHODS

Electronic databases, reviews, bibliographies, abstracts and conference proceedings were searched. Included trials had to be randomized or quasi-randomized and controlled, using bovine lactoferrin in the intervention group, treating Helicobacter-infected subjects and evaluating eradication of H. pylori as an outcome.

RESULTS

The search identified five eligible RCTs (of 169). Data were available for 682 subjects (bovine lactoferrin group-n = 316; control group-n = 366). The pooled odds ratio (five studies) for eradication by intention-to-treat analysis was 2.22 (95% CI 1.44-3.44; P = 0.0003) using the fixed effects model (FEM) and 2.24 (95% CI 1.15-4.35; P = 0.0003) using the random effects model (REM) (Cochran's Q = 6.83; P = 0.145). The pooled risk difference was 0.11 (95% CI 0.05-0.16; P = 0.0001) by FEM (Cochran's Q = 6.67; P = 0.154) and 0.10 (95% CI 0.04-0.17; P = 0.0023) by REM. There was no significant difference in incidence of adverse effects.

CONCLUSION

Bovine lactoferrin potentially improves H. pylori eradication rates without any impact on adverse effects, but available evidence is limited and further research is necessary to confirm the findings.

Helicobacter pylori eradication therapy success regarding different treatment period based on clarithromycin or metronidazole triple-therapy regimens

BACKGROUND

The study compares the eradication success of standard first-line triple therapies of different durations (7, 10, and 14 days).

MATERIALS AND METHODS

A total of 592 naive Helicobacter pylori-positive patients were randomized to receive pantoprazole, amoxicillin, and clarithromycin or metronidazole for 14 days (PACl14 or PAM14), 10 days (PACl10 or PAM10), or 7 days (PACl7 or PAM7). H. pylori eradication was assessed by histological, microbiological, and rapid urease examination.

RESULTS

The intention-to-treat (ITT) and per-protocol (PP) analyses have shown no overall statistically significant differences between the eradication success of PACl and PAM treatment groups (ITT p = .308, PP p = .167). Longer treatment duration has yielded statistically significant increase in eradication success for clarithromycin (ITT p = .004; PP p = .004) and metronidazole (ITT p = .010; PP p = .034) based regimens. Namely, PACl10, PACl14, and PAM14 protocols resulted in eradication success exceeding 80% in ITT and 90% in PP analysis. Primary resistance to clarithromycin and metronidazole equals 8.2% and 32.9%, respectively. Prolonging the metronidazole-based treatment duration in patients with resistant strains resulted in statistically significant higher eradication success.

CONCLUSIONS

For all antimicrobial combinations, 14 days protocols have led to a significant increase of H. pylori eradication success when compared to 10 and 7 days, respectively. Prolonging the treatment duration can overcome the negative effect of metronidazole resistance. Only PAM14, PACl10 protocols achieved ITT success > 80% and should be recommended as the first line eradication treatment in Croatia.

Efflux pump gene hefA of Helicobacter pylori plays an important role in multidrug resistance

AIM: To determine whether efflux systems contribute to multidrug resistance of H pylori.

METHODS: A chloramphenicol-induced multidrug resistance model of six susceptible H pylori strains (5 isolates and H pylori NCTC11637) was developed. Multidrug-resistant (MDR) strains were selected and the minimal inhibitory concentration (MIC) of erythromycin, metronidazole, penicillin G, tetracycline, and ciprofloxacin in multidrug resistant strains and their parent strains was determined by agar dilution tests. The level of mRNA expression of hefA was assessed by fluorescence real-time quantitative PCR. A H pylori LZ1026 knockout mutant (ΔH pylori LZ1026) for (putative) efflux protein was constructed by inserting the kanamycin resistance cassette from pEGFP-N2 into hefA, and its susceptibility profiles to 10 antibiotics were evaluated.

RESULTS: The MIC of six multidrug-resistant strains (including 5 clinical isolates and H pylori NCTC11637) increased significantly (≥ 4-fold) compared with their parent strains. The expression level of hefA gene was significantly higher in the MDR strains than in their parent strains (P = 0.033). A H pylori LZ1026 mutant was successfully constructed and the ΔH pylori LZ1026 was more susceptible to four of the 10 antibiotics. All the 20 strains displayed transcripts for hefA that confirmed the in vitro expression of these genes.

CONCLUSION: The efflux pump gene hefA plays an important role in multidrug resistance of H pylori.

Glutamate racemase as a target for drug discovery

The bacterial cell wall is a highly cross-linked polymeric structure consisting of repeating peptidoglycan units, each of which contains a novel pentapeptide substitution which is cross-linked through transpeptidation. The incorporation of D-glutamate as the second residue is strictly conserved across the bacterial kingdom. Glutamate racemase, a member of the cofactor-independent, two-thiol-based family of amino acid racemases, has been implicated in the production and maintenance of sufficient d-glutamate pool levels required for growth. The subject of over four decades of research, it is now evident that the enzyme is conserved and essential for growth across the bacterial kingdom and has a conserved overall topology and active site architecture; however, several different mechanisms of regulation have been observed. These traits have recently been targeted in the discovery of both narrow and broad spectrum inhibitors. This review outlines the biological history of this enzyme, the recent biochemical and structural characterization of isozymes from a wide range of species and developments in the identification of inhibitors that target the enzyme as possible therapeutic agents.

Expression, purification, crystallization and preliminary X-ray analysis of an NAD-dependent glyceraldehyde-3-phosphate dehydrogenase from Helicobacter pylori

Helicobacter pylori is a dangerous human pathogen that resides in the upper gastrointestinal tract. Little is known about its metabolism and with the onset of antibiotic resistance new treatments are required. In this study, the expression, purification, crystallization and preliminary X-ray diffraction of an NAD-dependent glyceraldehyde-3-phosphate dehydrogenase from H. pylori are reported.

What is new in the management of Helicobacter pylori?

Since the discovery of Helicobacter pylori in the early 1980s several treatment regimens have been developed to effectively treat this infection. International guidelines have allowed consensus on the best management and improved eradication rates. In recent years increasing antimicrobial resistance and falling eradication rates highlight the need for updated guidelines. In this article we review the most recent European management guidelines and in view of the unavailability of some drugs consider new treatment regimens for the management of H. pylori in Ireland.

A report card to grade Helicobacter pylori therapy

Helicobacter pylori causes a serious bacterial infectious disease, and the expectations of therapy should reflect this fact. Increasing antibiotic resistance, especially to clarithromycin, has significantly undermined the effectiveness of legacy triple therapy consisting of a proton pump inhibitor, clarithromycin, and amoxicillin. Current cure rates are consistently below 80% intention-to-treat, the accepted threshold separating acceptable from unacceptable treatment results. Grading clinical studies into effectiveness categories using prespecified criteria would allow clinicians to objectively identify and compare regimens. We offer a therapy report card similar to that used to grade the performance of school children. The intention-to-treat cure rate categories are: F or unacceptable ( 80%), D or poor (81-84%), C or fair (85-89%), B or good (90-95%), and A or excellent (95-100%). The category of "excellent" is based on the cure rates expected with other prevalent bacterial infectious diseases. We propose that only therapies that score "excellent" (grade = A) should be prescribed. Regimens scoring as B or "good" can be used if "excellent" results are not obtainable. In most regions legacy triple therapy should be abandoned as unacceptable. Quadruple therapy and sequential therapy are reasonable alternatives for initial therapy.