Review article: the treatment of refractory Helicobacter pylori infection

Multiple infections and cancer: implications in epidemiology

Approximately 18% of the global cancer burden has been attributed to infectious agents, with estimates ranging from 7% in developed countries to about 22% in developing countries. Chronic infections caused by the hepatitis B and C viruses, human papilloma viruses (HPV), and Helicobacter pylori (H. pylori) are reported to be responsible for approximately 15% of all human cancers. Interestingly, although many of the infectious agents that have been associated with cancer--such as HPV, Epstein-Barr virus (EBV), and H. pylori--are highly prevalent in the world, most infected individuals do not develop cancer but remain lifelong carriers. Malignancies associated with infectious agents may result from prolonged latency as a result of chronic infections. Pathogenic infections are necessary but are not sufficient for cancer initiation or progression. Cancer initiation may require additional cofactors, including secondary infections. Therefore, in patients with chronic infection with one agent, secondary co-infection with another agent may serve as an important co-factor that may cause cancer initiation and progression. Additionally, opportunistic co-infections could significantly inhibit response to cancer treatment and increase cancer mortality. Co-infections are relatively common in areas with a high prevalence of infectious agents, especially in developing countries. These co-infections can cause an imbalance in the host immune system by affecting persistence of and susceptibility to malignant infections. Several articles have been published that focus on infectious agents and cancer. In this article, we discuss the role of infectious agents in malignancies, highlight the role of multiple/co-infections in cancer etiology, and review implications for cancer epidemiology.

Antibiotic resistance of Helicobacter pylori isolated in the Southeast Coastal Region of China

BACKGROUND

The resistance of Helicobacter pylori (H. pylori) to antibiotics is increasing worldwide, lowering its efficacy in current eradication therapies. This study evaluated H. pylori resistance to antibiotics in the southeast coastal region of China and suggests appropriate alternatives.

MATERIALS AND METHODS

Seventeen thousand seven hundred and thirty one H. pylori strains were collected from eight areas of two provinces in coastal southeast China from 2010 to 2012. The resistance of these strains to six antibiotics was tested using the agar dilution method.

RESULTS

The resistance rates to clarithromycin, metronidazole, levofloxacin, amoxicillin, gentamicin and furazolidone were 21.5, 95.4, 20.6, 0.1, 0.1 and 0.1%, respectively. Double, triple and quadruple antibacterial resistant percentages were 25.5, 7.5 and 0.1%, respectively. A positive association between the resistance to levofloxacin and to clarithromycin was found, but there was a negative correlation in the resistances to levofloxacin and to metronidazole.

CONCLUSIONS

The prevalence of H. pylori resistance to clarithromycin, metronidazole, levofloxacin and multiple antibiotics in coastal southeast China is high. Choice of therapy should be individualized based on a susceptibility test in this region of the country.

[Clinical practice guideline on the management of patients with dyspepsia. Update 2012]

The aim of the Clinical Practice Guideline (CPG) on the Management of Patients with Dyspepsia is to generate recommendations on the optimal approach to dyspepsia in the primary care and specialized outpatient setting. The main objective of this CPG is to help to optimize the diagnostic process, identifying patients with a low risk of a serious organic disease (mainly tumoral), who could be safely managed without the need for invasive diagnostic tests and/or referral to a specialist. The importance of this aim lies in the need to accurately diagnose patients with esophagogastric cancer and correctly treat peptic ulcer while, at the same time, reduce negative endoscopies in order to appropriately use the available healthcare resources. This CPG reviews the initial strategies that can be used in patients with uninvestigated dyspepsia and evaluates the possible decision to begin empirical therapy or to investigate the existence of a lesion that could explain the symptoms. This CPG also discusses functional dyspepsia, which encompasses all patients with dyspepsia with no demonstrable cause on endoscopy. Recommendations for the diagnosis and treatment of peptic ulcer and Helicobacter pylori infection are also made. To classify the scientific evidence and strengthen the recommendations, the GRADE (Grading of Recommendations Assessment, Development and Evaluation Working Group) system has been used (http://www.gradeworkinggroup.org/).

[Clinical practice guideline on the management of patients with dyspepsia. Update 2012]

The aim of the Clinical Practice Guideline (CPG) on the Management of Patients with Dyspepsia is to generate recommendations on the optimal approach to dyspepsia in the primary care and specialized outpatient setting. The main objective of this CPG is to help to optimize the diagnostic process, identifying patients with a low risk of a serious organic disease (mainly tumoral), who could be safely managed without the need for invasive diagnostic tests and/or referral to a specialist. The importance of this aim lies in the need to accurately diagnose patients with esophagogastric cancer and correctly treat peptic ulcer while, at the same time, reduce negative endoscopies in order to appropriately use the available healthcare resources.This CPG reviews the initial strategies that can be used in patients with uninvestigated dyspepsia and evaluates the possible decision to begin empirical therapy or to investigate the existence of a lesion that could explain the symptoms. This CPG also discusses functional dyspepsia, which encompasses all patients with dyspepsia with no demonstrable cause on endoscopy. Recommendations for the diagnosis and treatment of peptic ulcer and Helicobacter pylori infection are also made. To classify the scientific evidence and strengthen the recommendations, the GRADE (Grading of Recommendations Assessment, Development and Evaluation Working Group) system has been used (http://www.gradeworkinggroup.org/).

Comparison of the Eradication Rate between 1- and 2-Week Bismuth-Containing Quadruple Rescue Therapies for Helicobacter pylori Eradication

Background/Aims

First-line therapies against Helicobacter pylori, including proton pump inhibitors (PPIs) plus two antibiotics, may fail in up to 20% of patients. 'Rescue' therapy is usually needed for patients who failed the first-line treatment. This study evaluated the eradication rate of bismuth-containing quadruple rescue therapy over a 1- or 2-week period.

Methods

We prospectively investigated 169 patients with a persistent H. pylori infection after the first-line triple therapy, which was administered from October 2008 to March 2010. The patients were randomized to receive a 1- or 2-week quadruple rescue therapy (pantoprazole 40 mg b.i.d., tripotassium dicitrate bismuthate 300 mg q.i.d., metronidazole 500 mg t.i.d., and tetracycline 500 mg q.i.d.). After the 'rescue' therapy, the eradication rate, compliance, and adverse events were evaluated.

Results

The 1-week group achieved 83.5% (71/85) and 87.7% (71/81) eradication rates in the intention to treat (ITT) and per-protocol (PP) analyses, respectively. The 2-week group obtained 87.7% (72/84) and 88.9% (72/81) eradication rate in the ITT and PP analyses, respectively. There was no significant difference in the eradication rate, patient compliance or rate of adverse events between the two groups.

Conclusions

One-week bismuth-containing quadruple therapy can be as effective as a 2-week therapy after the failure of the first-line eradication therapy.

A modified bismuth-containing quadruple therapy including a short course of furazolidone for Helicobacter pylori eradication after sequential therapy failure

BACKGROUND

 Helicobacter pylori eradication has still remained a challenge, especially in case of failure to novel treatments. Therefore, we designed a study to evaluate the effects of a modified bismuth-containing quadruple therapy including a short course of furazolidone on a group of patients whose sequential therapy had been unsuccessful.

MATERIALS AND METHODS

 Thirty-six H. pylori-positive patients who had previously failed a clarithromycin-containing sequential therapy enrolled the study. They received pantoprazole (40 mg-bid), amoxicillin (1 g-bid), and bismuth subcitrate (240 mg-bid) for 2 weeks and furazolidone (200 mg-bid) just during the first week. Eight weeks after treatment, H. pylori eradication was reassessed using C14-urea breath test.

RESULTS

Thirty five patients completed the study. H. pylori eradication rates were 80.6% (95% CI = 67.6-93.5) and 82.9% (95% CI = 70.6-95.2) according to intention-to-treat and per-protocol analyses, respectively. All patients had excellent compliance to treatment, and no one interrupted therapy owing to adverse effects.

CONCLUSION

 Regarding the eradication rate (>80%), low price, and very low adverse effects, a 2-week bismuth-containing quadruple regimen including a short course of furazolidone can be an encouraging regimen for second-line H. pylori eradication in case of sequential therapy failure. Possibly, it can be improved by alterations in dose, dosing intervals, and/or duration.

Blue light for infectious diseases: Propionibacterium acnes, Helicobacter pylori, and beyond?

Blue light, particularly in the wavelength range of 405-470 nm, has attracted increasing attention due to its intrinsic antimicrobial effect without the addition of exogenous photosensitizers. In addition, it is commonly accepted that blue light is much less detrimental to mammalian cells than ultraviolet irradiation, which is another light-based antimicrobial approach being investigated. In this review, we discussed the blue light sensing systems in microbial cells, antimicrobial efficacy of blue light, the mechanism of antimicrobial effect of blue light, the effects of blue light on mammalian cells, and the effects of blue light on wound healing. It has been reported that blue light can regulate multi-cellular behavior involving cell-to-cell communication via blue light receptors in bacteria, and inhibit biofilm formation and subsequently potentiate light inactivation. At higher radiant exposures, blue light exhibits a broad-spectrum antimicrobial effect against both Gram-positive and Gram-negative bacteria. Blue light therapy is a clinically accepted approach for Propionibacterium acnes infections. Clinical trials have also been conducted to investigate the use of blue light for Helicobacter pylori stomach infections and have shown promising results. Studies on blue light inactivation of important wound pathogenic bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa have also been reported. The mechanism of blue light inactivation of P. acnes, H. pylori, and some oral bacteria is proved to be the photo-excitation of intracellular porphyrins and the subsequent production of cytotoxic reactive oxygen species. Although it may be the case that the mechanism of blue light inactivation of wound pathogens (e.g., S. aureus, P. aeruginosa) is the same as that of P. acnes, this hypothesis has not been rigorously tested. Limited and discordant results have been reported regarding the effects of blue light on mammalian cells and wound healing. Under certain wavelengths and radiant exposures, blue light may cause cell dysfunction by the photo-excitation of blue light sensitizing chromophores, including flavins and cytochromes, within mitochondria or/and peroxisomes. Further studies should be performed to optimize the optical parameters (e.g., wavelength, radiant exposure) to ensure effective and safe blue light therapies for infectious disease. In addition, studies are also needed to verify the lack of development of microbial resistance to blue light.

Eradication Treatment of Helicobacter pylori Infection: Its Importance and Possible Relationship in Preventing the Development of Gastric Cancer

Helicobacter pylori is the most important carcinogen for gastric adenocarcinoma. Bacterial virulence factors are essential players in modulating the immune response involved in the initiation of carcinogenesis in the stomach; host genetic factors contribute to the regulation of the inflammatory response and to the aggravation of mucosal damage. In terms of environmental factors, salt intake and smoking contribute to the development of lesions. Various therapeutic schemes are proposed to eradicate H. pylori infection, which could potentially prevent gastric cancer, offering the greatest benefit if performed before premalignant changes of the gastric mucosa have occurred.

The challenge of Helicobacter pylori resistance to antibiotics: the comeback of bismuth-based quadruple therapy

A proton-pump inhibitor (PPI), clarithromycin-based, triple therapy has been the recommended treatment for Helicobacter pylori eradication for the past 15 years. Due to a steady increase in H. pylori resistance to clarithromycin, this triple clarithromycin-based treatment has become progressively less efficacious. Several approaches are available to address this situation: one is to test for clarithromycin resistance so that this triple clarithromycin-based regimen is given only to those who will benefit; a second is to prescribe the drugs sequentially, beginning with amoxicillin and a PPI followed by clarithromycin and metronidazole, again with a PPI or the four drugs prescribed concomitantly; a third alternative is to use bismuth-based quadruple therapy, PPI plus a standardized three-in-one capsule, bismuth subcitrate potassium, metronidazole, and tetracycline (BMT, sold under licence as Pylera®). The advantages of these different approaches are reviewed, including the relevance of BMT three-in-one capsule in clinical practice.

Review article: rifabutin in the treatment of refractory Helicobacter pylori infection

BACKGROUND

Even with the current most effective treatment regimens, a relevant proportion of patients will fail to eradicate Helicobacter pylori infection.

AIM

To evaluate the role of rifabutin in the treatment of H. pylori infection.

METHODS

Bibliographical searches were performed in MEDLINE. Data on the efficacy of rifabutin-containing regimens on H. pylori eradication were combined and meta-analysed using the generic inverse variance method.

RESULTS

Rifabutin shows good in vitro activity against H. pylori. Mean H. pylori rifabutin resistance rate (calculated from 11 studies including 2982 patients) was 1.3% (95% confidence interval = 0.9-1.7%). When only studies including patients naïve to H. pylori eradication treatment were considered, this figure was even lower (0.6%). On the other hand, higher values of rifabutin resistance were calculated (1.59%) when only post-treatment patients were considered. Overall, mean H. pylori eradication rate (intention-to-treat analysis) with rifabutin-containing regimens (1008 patients) was 73% (67-79%). Respective cure rates for second-line (223 patients), third-line (342 patients) and fourth/fifth-line (95 patients) rifabutin therapies were 79% (67-92%), 66% (55-77%) and 70% (60-79%) respectively. For treating H. pylori infection, almost all studies have administered rifabutin 300 mg/day; this dose seems to be more effective than 150 mg/day. The ideal length of treatment remains unclear, but 10- to 12-day regimens are generally recommended. The mean rate of adverse effects was 22% (19-25%). Myelotoxicity is the most significant, although this complication was rare. Until now, all patients have recovered of leucopenia uneventfully in a few days, and there have been no reports of infection or other adverse outcomes related to it.

CONCLUSION

Rifabutin-containing rescue therapy constitutes an encouraging strategy after multiple (usually three) previous eradication failures with key antibiotics such as amoxicillin, clarithromycin, metronidazole, tetracycline and levofloxacin.

Modified Sequential Therapy Regimen versus Conventional Triple Therapy for Helicobacter Pylori Eradication in Duodenal Ulcer Patients in China: A Multicenter Clinical Comparative Study

Objective. Antimicrobial resistance has decreased eradication rates for Helicobacter pylori infection worldwide. To observe the effect of eradicating Helicobacter pylori (H. pylori) and the treatment of duodenal ulcer by 2 kinds of modified sequential therapy through comparing with that of 10-day standard triple therapy. Methods. A total of 210 patients who were confirmed in duodenal ulcer active or heal period by gastroscopy and H. pylori positive confirmed by rapid urease test, serum anti-H. pylori antibody (ELASE), or histological examination enrolled in the study. All the patients were randomly divided into three groups: group A (70 cases) and group B (70 cases) were provided 10-day modified sequential therapy; group C (70 cases) was provided 10-day standard triple therapy. Patients of group A received 20 mg of Esomeprazole, 500 mg of Clarithromycin for the first 5 days, followed by 20 mg of Esomeprazole, 500 mg of Clarithromycin, and 1000 mg of Amoxicillin for the remaining 5 days. Group B received 20 mg of Esomeprazole, 1000 mg of Amoxicillin for the first 5 days, followed by 20 mg of Esomeprazole, 500 mg of Clarithromycin, and 1000 mg of Amoxicillin for the remaining 5 days. Group C received 20 mg of Esomeprazole, 500 mg of Clarithromycin, and 1000 mg of Amoxicillin for standard 10-day therapy. All drugs were given twice daily. H. pylori eradication rate was checked four to eight weeks after taking the medicine by using a ¹³C urea breath test. In the first, second, third, seventh, twenty-first, thirty-fifth days respectively, the symptoms of patients such as epigastric gnawing, burning pain, and acidity were evaluated simultaneously. Results. Overall, 210 patients accomplished all therapy schemes, 9 case patients were excluded. The examination result indicated that the H. pylori eradication rate of each group was as follows: group A 92.5% (62/67), group B 86.8% (59/68), and group C 78.8% (52/66). The H. pylori eradication rate of group A was slightly higher than group B (P < 0.05) and both of them were obviously higher than group C (P < 0.05). Modified sequential therapy was significantly more effective in patients with clarithromycin-resistant strains (80%/67% versus 31%; P = 0.02). Symptoms improvement: all the three groups could improve the symptoms such as epigastric gnawing, burning pain, and acidity since the first day. There was no significant difference in total score descending of symptoms between each group (P > 0.05). Conclusions. All the three therapy schemes could alleviate symptoms of duodenal ulcer patients in China efficiently. But as far as eradicating H. pylori is concerned, the modified sequential therapy was better than standard triple therapy, especially the therapy scheme used in group A.

Influence of pretreatment with H2 receptor antagonists on the cure rates of Helicobacter pylori eradication

Background

Pretreatment with a proton pump inhibitor (PPI) reportedly decreases the efficacy of Helicobacter pylori (H. pylori) eradication, however, the effect of pretreatment with an H2 receptor antagonist (H2RA) on H. pylori eradication has not yet been studied. We compared the efficacy of eradication regimen (lansoprazole/amoxicillin/clarithromycin) in patients with H. pylori infection with or without H2RA pretreatment.

Material/Methods

In this retrospective study conducted at three centers, 310 patients with H. pylori infection were treated. The diagnosis of H. pylori infection was made using the rapid urease test, bacterial cultures and histological examination of endoscopic biopsy specimens. The patients were assigned to receive an eradication regimen first or following pretreatment with H2RA. Eradication was assessed using the ¹³C-urea breath test more than 4 weeks after the completion of therapy.

Results

Overall, H. pylori was eradicated in 79.7% of the cases: the eradication rate was 81.6% in the pretreatment group, and 77.6% in the eradication first group (p=0.3799, chi-square test). No significant difference in the eradication rate was observed between the two groups.

Conclusions

Pretreatment with H2RA had no significant influence on the efficacy of H. pylori eradication therapy.

Inhibitory potential of tea polyphenolics and influence of extraction time against Helicobacter pylori and lack of inhibition of beneficial lactic acid bacteria

Tea polyphenolics such as catechins are known to have the potential to inhibit many bacterial pathogens. Helicobacter pylori has been identified as an etiologic agent in the development of gastric ulcer, peptic ulcer, gastritis, and many other stomach-related diseases. In this study, we investigated the effect of 9 tea extracts--3 different brands representing 4 different processed types (white, green, oolong, and black)--on the inhibition of H. pylori. Extraction times of 2 and 5 minutes were compared. Most 5-minute extracts showed H. pylori inhibition, whereas 2-minute extracts only of Choice darjeeling black and Tazo white showed inhibition. No recovery was observed after the addition of 0.5 and 5 mM proline, indicating that tea polyphenols do not inhibit H. pylori by inhibition of proline oxidation via proline dehydrogenase. Extracts that showed inhibition were further evaluated for their effect on beneficial lactic acid bacteria. None of the samples showed inhibition, suggesting that tea might be able to inhibit H. pylori without affecting the beneficial lactic acid bacteria. High-performance liquid chromatography indicated the presence of gallic acid, quercetin, caffeine, and tea catechins (including catechin, epicatechin, and epigallocatechin) in all the tea samples. Our study indicates that tea can be potentially used as a low-cost dietary support to combat H. pylori-linked gastric diseases without affecting the beneficial intestinal bacteria.

A clinician's guide to salvage therapy for persistent Helicobacter pylori infection

Since its discovery in 1982, Helicobacter pylori has been established as a common cause of gastritis and peptic ulcer disease. H pylori infection is also closely associated with several gastric malignancies and has consequently been designated a human carcinogen. As these associations have become increasingly recognized and pursued, a growing challenge facing today's clinicians is the management of patients with persistent H pylori despite previous attempts to treat the infection. In developed countries, the most popular treatment regimen remains traditional triple therapy consisting of a proton pump inhibitor, clarithromycin, and amoxicillin for 7 to 14 days. Unfortunately, eradication rates with traditional triple therapy are disappointing, with infection persisting in as many as 25% of those treated. This article addresses the management of patients with persistent H pylori infection, including indications for confirmatory testing, reasons for treatment failure, and established and emerging salvage regimens for patients with persistent infection.

Helicobacter pylori infection: a randomized, controlled study comparing 2 rescue therapies after failure of standard triple therapies

Antibiotic resistance to amoxicillin in second-line eradication therapy for Helicobacter pylori infection is much less frequent than resistance to metronidazole. We conducted a randomized, controlled study to compare the efficacies of standard quadruple rescue therapy and a new therapy with amoxicillin replacing metronidazole for patients failing first-line eradication treatment. We randomly assigned 120 patients who failed H. pylori eradication using a proton pump inhibitor plus clarithromycin and amoxicillin to undergo a 1-week rescue therapy with esomeprazole, bismuth subcitrate, and tetracycline plus either metronidazole (EBTM group, n = 62) or amoxicillin (EBTA group, n = 58). We used follow-up endoscopy 8 weeks after the end of treatment to assess the treatment response. We also examined and analyzed antibiotic resistances and CYP2C19 genotypes. Intention-to-treat analysis demonstrated that the EBTA group had a significantly lower eradication rate than the EBTM group (62% vs. 81%, respectively, p = 0.02). Per-protocol analysis showed similar results (64% vs. 83%, p = 0.01). However, the EBTA group had less frequency of adverse events than the EBTM group (19% vs. 44%, p < 0.01). Both groups had good drug compliance (both 97%). Antibiotic susceptibility tests showed that the frequency of amoxicillin-resistant strains was much less than that of metronidazole-resistant strains (0% vs. 54%, respectively), and there were no significant differences between H. pylori eradication rates and antibiotic resistances. In conclusion, EBTA quadruple therapy demonstrated a lower eradication rate than standard EBTM therapy in second-line rescue treatment. The discrepancy between in vitro antibiotic susceptibility and in vivo eradication response is probably due to drug interactions between combined antibiotics or some unknown causes, and should not be neglected in H. pylori therapy.

Moxifloxacin-containing triple therapy versus bismuth-containing quadruple therapy for second-line treatment of Helicobacter pylori infection: a meta-analysis

BACKGROUND

Moxifloxacin-containing triple therapy has been suggested as an alternative second-line therapy for Helicobacter pylori infection.

AIMS

To systematically review the efficacy and tolerance of moxifloxacin-containing triple therapy in second-line H. pylori eradication, and to conduct a meta-analysis of studies comparing this regimen with bismuth-containing quadruple therapy.

MATERIALS AND METHODS

 Electronic databases including Medline, Embase, Cochrane controlled trials register, Web of Science, PubMed, Chinese Biomedical Literature Database (updated to December 2010), and manual searches were conducted. A meta-analysis of all randomized controlled trials (RCTs) comparing moxifloxacin-containing triple therapy to bismuth-containing quadruple therapy in the second-line treatment of H. pylori infection was performed.

RESULTS

Seven RCTs including 787 patients were assessed. The meta-analysis showed that the eradication rate in the moxifloxacin group was significantly higher than that in the quadruple therapy group (74.9 vs 61.4%, OR 1.89, 95% CI: 1.38-2.58, p < .0001); besides, the rates of side effects and discontinuing therapy because of side effects in the moxifloxacin group were significantly lower than those in the quadruple therapy group (side effects: 10.1 vs 27.8%, OR 0.27, 95% CI: 0.18-0.41, p < .00001; discontinuing therapy because of side effects: 1.4 vs 8.2%, OR 0.18, 95% CI: 0.08-0.40, p < .0001). These results were constant in the sensitivity analyses.

CONCLUSION

Moxifloxacin-containing triple regimen is more effective and better tolerated than the bismuth-containing quadruple therapy in the second-line treatment of H. pylori infection.

Treatment of Helicobacter pylori infection 2010

It is accepted that the success of Helicobacter pylori eradication treatment using standard triple therapy is declining. Resistance, particularly to clarithromycin, has been shown in numerous countries to be rising to a level where the use of standard triple therapy in its current form may no longer be justified. The two major factors influencing resistance are prior exposure to the antibiotic and compliance with therapy. Regimes based on bismuth and levofloxacin, which had previously been mainly second-line options, are now emerging as superior first-line options. Trials of sequential and concomitant therapies are also showing the usefulness of these treatments in different populations. Options for third and subsequent line therapies include furazolidone and rifabutin-based regimes. Susceptibility testing should be performed to maintain accurate data on resistance levels, and has also clinical utility in difficult to eradicate cases. None of these, however, will be successful unless compliance is improved upon. If compliance is assured and eradication confirmation pursued, it has been repeatedly illustrated that near full eradication is achievable.

Invasion and multiplication of Helicobacter pylori in gastric epithelial cells and implications for antibiotic resistance

Helicobacter pylori is a Gram-negative, spiral-shaped bacterium that infects more than 50% of the human population and can cause gastritis, peptic ulcer, or gastric malignancies. It is generally viewed as an extracellular microorganism. In a gentamicin protection assay on AGS or MKN45 cells, H. pylori could invade the epithelial cells and multiply within double-layer vesicles either on the plasma membrane or in the cytoplasm. A 5-fold increase in the number of bacteria was recultured from the infected cells at 12 h, compared with the number of invading cells at 2.5 h postinfection. The autophagic vesicles induced by H. pylori are the sites of replication and also of the degradation of the replicating bacteria after fusion with lysosomes. Many H. pylori bacteria in coccoid form associated with the plasma membrane can be released into culture. Only cell-penetrating antibiotics can enhance the intracellular killing of the replicating bacteria. The multiplication of H. pylori within cells provides a niche for its resistance to antibacterial therapy and has a significant impact on its biological life cycle.

High efficacy of 14-day triple therapy-based, bismuth-containing quadruple therapy for initial Helicobacter pylori eradication

BACKGROUND

The success rate of currently recommended 7-day triple therapy with a PPI plus amoxicillin and clarithromycin has fallen into the unacceptable range. It is urgent to look for a new strategy to treat the infection of Helicobacter pylori.

AIMS

To observe the efficacy of triple therapy-based, bismuth-containing quadruple therapy for H. pylori treatment.

METHODS

A total of 160 patients with functional dyspepsia who were Hp+ were randomly assigned into two groups. Regimen: Omeprazole 20 mg, Amoxicillin 1.0 g, Clarithromycin 500 mg and Bismuth Potassium Citrate 220 mg, twice a day. Eighty patients received 7-day quadruple therapy and 80 patients received the same therapy for 14 days. Six weeks after treatment, H. pylori eradication was assessed by (13)C-urea breath test. Minimal inhibitory concentrations of metronidazole, clarithromycin and amoxicillin of clinical isolates were determined by the twofold agar dilution method.

RESULTS

Fourteen-day therapy led to a significant increase of H. pylori eradication success when compared to 7-day therapy in the intention-to-treat analysis (93.7 vs 80.0%; p = .01), and the per-protocol analysis (97.4 vs 82.0%; p = .0016). The H. pylori resistance rates to metronidazole, clarithromycin and amoxicillin were 42.1, 18.0 and 0%. Fourteen-day therapy was significantly more effective in patients with clarithromycin-resistant strains. Incidences of adverse events were comparable.

CONCLUSIONS

Addition bismuth and prolonging treatment duration can overcome H. pylori resistance to clarithromycin and decrease the bacterial load. Fourteen-day triple therapy-based, bismuth-containing quadruple therapy achieved ITT success rate 93% and could be recommended as the first line eradication regimen.

Regulatory circuits in Helicobacter pylori : network motifs and regulators involved in metal-dependent responses

The ability of Helicobacter pylori, one of the most successful human bacterial pathogens, to colonize the acidic gastric niche persistently, depends on the proper homeostasis of intracellular metal ions, needed as cofactors of essential metallo-proteins involved in acid acclimation, respiration and detoxification. This fundamental task is controlled at the transcriptional level mainly by the regulators Fur and NikR, involved in iron homeostasis and nickel response, respectively. Herein, we review the molecular mechanisms that underlie the activity of these key pleiotropic regulators. In addition, we will focus on their involvement in the transcriptional regulatory network of the bacterium, pinpointing a surprising complexity of network motifs that interconnects them and their gene targets. These motifs appear to confer versatile dynamics of metal-dependent responses by extensive horizontal connections between the regulators and feedback control of metal-cofactor availability.

A randomized controlled trial: efficacy and safety of azithromycin, ofloxacin, bismuth, and omeprazole compared with amoxicillin, clarithromycin, bismuth, and omeprazole as second-line therapy in patients with Helicobacter pylori infection

BACKGROUND

Helicobacter pylori infection of the stomach is widespread among human populations and is considered to play a major role in the pathogenesis of various diseases such as peptic ulcer, adenocarcinoma, and mucosa associated lymphoid tissue (MALT) lymphoma of the stomach. To increase H. pylori eradication rate without increasing bacterial resistance, various regimens have been recommended. Commonly the association of at least two antibiotics with a proton-pump inhibitor is used. The treatment regimens for second-line therapy, suggested in studies from the western world may not be ideal in Iran.

AIM

In this study, we evaluated the safety and efficacy of a new quadruple therapy regimen and compared it with the standard second-line treatment for H. pylori eradication.

METHODS

We selected 220 H. pylori positive patients, with a clear indication of eradication therapy, who did not respond to a 2 weeks treatment with metronidazole, amoxicillin, omeprazole, and bismuth. They were randomized into two groups. Group A (n = 110) were treated with azithromycin, ofloxacin, bismuth, and omeprazole and group B (n = 110) with amoxicillin, clarithromycin, bismuth, and omeprazole for 2 weeks. Four weeks after the end of treatment, urea breath test was performed for all subjects to confirm eradication.

RESULTS

In intention-to-treat analysis, the rate of H. pylori eradication in groups A and B was 77.3% (85/110) and 64.5% (71/110) respectively (p = .027). In per-protocol analysis, the rate of H. pylori eradication in groups A and B was 86.7 and 74.7%, respectively (p = .026). The incidence of poor compliance was lower, although not significantly so, in group A than group B (3.5 vs 4.3%). No major adverse events occurred in both groups.

CONCLUSION

Two weeks of treatment with ofloxacin, azithromycin, omeprazole, and bismuth is an effective and safe regimen for H. pylori eradication as second-line therapy.

CYP2C19 genotypes in the pharmacokinetics/pharmacodynamics of proton pump inhibitor-based therapy of Helicobacter pylori infection

IMPORTANCE OF THE FIELD

Proton pump inhibitors (PPIs) are potent gastric acid inhibitors. Therapies with a PPI and antibiotics are used to cure Helicobacter pylori (H. pylori) infection, which is closely related to many gastrointestinal diseases. Most PPIs are mainly metabolized by cytochrome 2C19 (CYP2C19). The genetic polymorphisms of CYP2C19 may lead to the differences in pharmacokinetics (PK), pharmacodynamics (PD) and clinical efficacy of PPIs.

AREAS COVERED IN THIS REVIEW

The roles of PPIs on the eradication of H. pylori are summarized. The impact f CYP2C19 polymorphism on the PK and PD of PPIs is addressed and related to the present status of therapy for H. pylori infection. The opinions on the strategy of PPIs-based therapies of H. pylori infection are provided.

WHAT THE READER WILL GAIN

Update the factors that may influence the PPIs-based therapies of H. pylori infection.

TAKE HOME MESSAGE

The eradication rates of H. pylori infection are significantly different between patients who are CYP2C19 extensive metabolizers and poor metabolizers, partly because of the differences in the PK and PD of PPIs. Nonetheless, the differences can be improved by adjusting the regimens of PPIs and using antibiotics that have less H. pylori-resistance.

Empiric quadruple vs. triple therapy for primary treatment of Helicobacter pylori infection: Systematic review and meta-analysis of efficacy and tolerability

OBJECTIVES

Recent treatment guidelines recommend two first-line therapies for Helicobacter pylori infection: proton pump inhibitor (PPI), bismuth, tetracycline, and metronidazole (quadruple therapy) or PPI, clarithromycin, and amoxicillin (triple therapy). We performed a systematic review and meta-analysis to compare the efficacy and tolerability of these regimens as first-line treatment of H. pylori.

METHODS

A search of MEDLINE, EMBASE, Google Scholar, the Cochrane Central Register of Controlled Trials, ACP Journal Club, the Database of Abstracts of Reviews of Effectiveness, Cochrane Methodology Register, Health Technology Assessment Database, and abstracts from prominent gastrointestinal scientific meetings was carried out. Randomized controlled trials (RCTs) comparing bismuth quadruple therapy to clarithromycin triple therapy were selected for meta-analysis. Two independent reviewers extracted data, using standardized data forms. Meta-analysis was carried out with the metan command in Stata 10.1. Funnel plots and subgroup analyses were carried out.

RESULTS

Nine RCTs (N=1,679) were included. Although dosing regimens of clarithromycin triple therapy were quite consistent between trials, dosing regimens varied considerably for bismuth quadruple therapy. Bismuth quadruple therapy achieved eradication in 78.3% of patients, whereas clarithromycin triple therapy achieved an eradication rate of 77.0% (risk ratio (RR)=1.002, 95% confidence interval (CI): 0.936-1.073). There was moderate heterogeneity and no evidence for significant publication bias. Subgroup analyses by study location, treatment duration, and study population did not account for the heterogeneity. There were no statistically significant differences in side effects yielded by quadruple vs. clarithromycin triple therapy (RR=1.04, 95% CI: 1.04-1.14).

CONCLUSIONS

Quadruple and triple therapies yielded similar eradication rates as primary therapy for H. pylori infection. Both therapies yielded suboptimal eradication rates. Patient compliance and side effects are similar for quadruple and triple therapies.

Helicobacter pylori: diagnosis and treatment

PURPOSE OF REVIEW

Multiple diagnostic methods and treatment strategies have been developed to detect and treat the Helicobacter pylori infection. Many of them have stood the test of time; others lost their value with the introduction of new test and treatment modalities. This review focuses on the current diagnostic methods and their clinical implications, as well as on established and novel treatment strategies.

RECENT FINDINGS

The increasing antimicrobial resistance has resulted in a decline of the success rate of recommended eradication regimens. The current guidelines recommend as first-line treatment clarithromycin, amoxicillin or metronidazole, and proton pump inhibitor twice daily, but recent studies have demonstrated an increasing eradication failure with these regimens. Several treatment modifications have been adopted regarding duration and combination of substances.

SUMMARY

The currently recommended first-line treatments are effective and well tolerated. In areas with high antimicrobial resistance rates, new antibiotic combinations and modifications in the sequence of drug administration are proposed as alternative treatment options to standard triple therapy. Future treatment strategies have to focus on regional antimicrobial resistance adopted treatment selection and the development of new antibiotics.

Second-line rescue therapy of helicobacter pylori infection

Helicobacter pylori infection is the main known cause of gastritis, gastroduodenal ulcer disease and gastric cancer. After more than 20 years of experience in H. pylori treatment, however, the ideal regimen to treat this infection has still to be found. Nowadays, apart from having to know well first-line eradication regimens, we must also be prepared to face treatment failures. Therefore, in designing a treatment strategy we should not focus on the results of primary therapy alone, but also on the final (overall) eradication rate. The choice of a 'rescue' treatment depends on which treatment is used initially. If a first-line clarithromycin-based regimen was used, a second-line metronidazole-based treatment (quadruple therapy) may be used afterwards, and then a levofloxacin-based combination would be a third-line 'rescue' option. Alternatively, it has recently been suggested that levofloxacin-based 'rescue' therapy constitutes an encouraging second-line strategy, representing an alternative to quadruple therapy in patients with previous PPI-clarithromycin-amoxicillin failure, with the advantage of efficacy, simplicity and safety. In this case, quadruple regimen may be reserved as a third-line 'rescue' option. Finally, rifabutin-based 'rescue' therapy constitutes an encouraging empirical fourth-line strategy after multiple previous eradication failures with key antibiotics such as amoxicillin, clarithromycin, metronidazole, tetracycline, and levofloxacin. Even after two consecutive failures, several studies have demonstrated that H. pylori eradication can finally be achieved in almost all patients if several 'rescue' therapies are consecutively given. Therefore, the attitude in H. pylori eradication therapy failure, even after two or more unsuccessful attempts, should be to fight and not to surrender.

Treatment of Helicobacter pylori infection

This article aims to examine current best practice in the field reference to first-line, second-line, rescue and emerging treatment regimens for Helicobacter pylori eradication. The recommended first-line treatment in published guidelines in Europe and North American is proton pump inhibitor combined with amoxicillin and clarithromycin being the favoured regimen. Rates of eradication with this regimen however are falling alarmingly due to a combination of antibiotic resistance and poor compliance with therapy. Bismuth based quadruple therapies and levofloxacin based regimes have been shown to be effective second line regimens. Third-line options include regimes based on rifabutin or furazolidone, but susceptibility testing is the most rational option here, but is currently not used widely enough. Sequential therapy is promising but needs further study and validation outside of Italy. Although the success of first line treatments is falling, if compliance is good and a clear treatment paradigm adhered to, almost universal eradication rates can still be achieved. If compliance is not achievable, the problem of antibiotic resistance will continue to beset any combination of drugs used for H. pylori eradication.

In vitro antibacterial activity of acyl-lysyl oligomers against Helicobacter pylori

The gastric pathogen Helicobacter pylori has developed resistance to virtually all current antibiotics; thus, there is a pressing need to develop new anti-H. pylori therapies. The goal of this work was to evaluate the antibacterial effect of oligo-acyl-lysyl (OAK) antimicrobial peptidomimetics to determine if they might represent alternatives to conventional antibiotic treatment of H. pylori infection. A total of five OAK sequences were screened for growth-inhibitory and/or bactericidal effects against H. pylori strain G27; four of these sequences had growth-inhibitory and bactericidal effects. The peptide with the highest efficacy against strain G27, C12K-2beta12, was selected for further characterization against five additional H. pylori strains (26695, J99, 7.13, SS1, and HPAG1). C12K-2beta12 displayed MIC and minimum bactericidal concentration (MBC) ranges of 6.5 to 26 microM and 14.5 to 90 microM, respectively, across the six strains after 24 h of exposure. G27 was the most sensitive H. pylori strain (MIC = 6.5 to 7 microM; MBC = 15 to 20 microM), whereas 26695 was the least susceptible strain (MIC = 25 to 26 microM; MBC = 70 to 90 microM). H. pylori was completely killed after 6 to 8 h of incubation in liquid cultures containing two times the MBC of C12K-2beta12. The OAK demonstrated strong in vitro stability, since efficacy was maintained after incubation at extreme temperatures (4 degrees C, 37 degrees C, 42 degrees C, 50 degrees C, 55 degrees C, 60 degrees C, and 95 degrees C) and at low pH, although reduced killing kinetics were observed at pH 4.5. Additionally, upon transient exposure to the bacteria, C12K-2beta12 showed irreversible and significant antibacterial effects and was also nonhemolytic. Our results show a significant in vitro effect of C12K-2beta12 against H. pylori and suggest that OAKs may be a valuable resource for the treatment of H. pylori infection.

Characterization of clarithromycin resistance in Malaysian isolates of Helicobacter pylori

AIM: To characterize the types of mutations present in the 23S rRNA genes of Malaysian isolates of clarithromycin-resistant Helicobacter pylori (H pylori).

METHODS: Clarithromycin susceptibility of H pylori isolates was determined by E test. Analyses for point mutations in the domain V of 23S rRNA genes in clarithromycin-resistant and -sensitive strains were performed by sequence analysis of amplified polymerase chain reaction products. Restriction fragment length polymorphism was performed using BsaI and MboII enzymes to detect restriction sites that correspond to the mutations in the clarithromycin-resistant strains.

RESULTS: Of 187 isolates from 120 patients, four were resistant to clarithromycin, while 183 were sensitive. The MIC of the resistant strains ranged from 1.5 to 24 &mgr;g/mL. Two isolates had an A2142G mutation and another two had A2143G mutations. A T2182C mutation was detected in two out of four clarithromycin-resistant isolates and in 13 of 14 clarithromycin-sensitive isolates. Restriction enzyme analyses with BsaI and MboII were able to detect the mutations.

CONCLUSION: Clarithromycin resistance is an uncommon occurrence among Malaysian isolates of H pylori strains and the mutations A2142G and A2143G detected were associated with low-level resistance.

Efficacy of a 7-day course of furazolidone, levofloxacin, and lansoprazole after failed Helicobacter pylori eradication

Background

Increasing resistance to clarithromycin and nitroimidazole is the main cause of failure in the Helicobacter pylori eradication. The ideal retreatment regimen remains unclear, especially in developing countries, where the infection presents high prevalence and resistance to antibiotics. The study aimed at determining the efficacy, compliance and adverse effects of a regimen that included furazolidone, levofloxacin and lansoprazole in patients with persistent Helicobacter pylori infection, who had failed to respond to at least one prior eradication treatment regimen.

Methods

This study included 48 patients with peptic ulcer disease. Helicobacter pylori infection was confirmed by a rapid urease test and histological examination of samples obtained from the antrum and corpus during endoscopy. The eradication therapy consisted of a 7-day twice daily oral administration of lansoprazole 30 mg, furazolidone 200 mg and levofloxacin 250 mg. Therapeutic success was confirmed by a negative rapid urease test, histological examination and 14C- urea breath test, performed 12 weeks after treatment completion. The Chi-square method was used for comparisons among eradication rates, previous treatments and previous furazolidone use.

Results

Only one of the 48 patients failed to take all medications, which was due to adverse effects (vomiting). Per-protocol and intention-to-treat eradication rates were 89% (95% CI- 89%–99%) and 88% (88–92%), respectively. Mild and moderate adverse effects were reported by 41 patients (85%). For patients with one previous treatment failure, the eradication rate was 100%. Compared to furazolidone-naïve patients, eradication rates were lower in those who had failed prior furazolidone-containing regimen(s) (74% vs. 100%, p = 0.002).

Conclusion

An empiric salvage-regimen including levofloxacin, furazolidone and lansoprazole is very effective in the eradication of Helicobacter pylori, particularly in patients that have failed one prior eradication therapy.

Fluorescence in situ hybridization confirms clearance of visible Helicobacter spp. associated with gastritis in dogs and cats

BACKGROUND

The results of studies examining the role of Helicobacter spp. in the pathogenesis of canine and feline gastritis are inconclusive. Furthermore, data evaluating the effectiveness of medical therapy for eradication of Helicobacter infection are limited.

AIM

To detect Helicobacter spp. in mucosal biopsies of dogs and cats diagnosed with gastritis, with fluorescence in situ hybridization (FISH).

ANIMALS

Three dogs and 2 cats with signs of chronic gastrointestinal disease.

METHODS

Dogs and cats infected with Helicobacter spp. were treated with triple antimicrobial therapy and fed an elimination diet for 21 days. Helicobacter spp. status in endoscopic (3 dogs, 1 cat) or surgical biopsies (1 cat) of gastric mucosa was compared pre- and posttreatment in each animal by histology, FISH analysis, and polymerase chain reaction (PCR).

RESULTS

Gastritis of varying severity with intraglandular spiral bacteria was observed in all animals. Pretreatment diagnostic tests confirmed the presence of mucosal Helicobacter spp. in all animals by FISH and histopathology and in 4/5 animals by PCR. Rapid resolution of vomiting episodes was observed in all animals. Gastric biopsies performed after triple therapy revealed clearance of visible Helicobacter spp. by histopathology and negative FISH analysis, as well as PCR in all animals.

CONCLUSIONS AND CLINICAL IMPORTANCE

Application of FISH to routine biopsy specimens enabled rapid and specific identification of Helicobacter spp. within the gastric mucosa of dogs and cats. Although medical therapy was useful in resolution of clinical signs and clearance of visible Helicobacter spp. in gastric biopsies, gastric inflammation persisted.

Second-line treatment for Helicobacter pylori infection based on moxifloxacin triple therapy: a randomized controlled trial

BACKGROUND

In eradication of Helicobacter pylori infection, standard quadruple second-line therapy consisting of proton pump inhibitor (PPI), bismuth, metronidazole and tetracycline often fails and shows poor patient compliance. The aim of our study was to evaluate the efficacy and tolerability of moxifloxacin-based triple therapy as an alternative second-line protocol.

METHODS

A total of 160 patients, in whom the initial standard PPI triple therapy had failed to eradicate H. pylori infection, were included in the study. The initial H. pylori status was assessed using the (13)C-urea breath test. Patients were randomized to one of the following 7-day treatment regimens: (1) OMM: omeprazole 20 mg twice a day, moxifloxacin 400 mg/day, metronidazole 500 mg three times a day; and (2) OBMT: omeprazole 20 mg twice a day, colloidal bismuth subcitrate 120 mg four times a day, metronidazole 500 mg three times a day, tetracycline 500 mg four times a day. Patient compliance and adverse events were evaluated one week after completion of therapy. H. pylori status was re-assessed with the (13)C-urea breath test six weeks after the end of therapy.

RESULTS

The eradication rates were 73.2% (60/82) and 78.9% (60/76) with moxifloxacin-based triple therapy, and 53.8% (42/78) and 64.6% (42/65) with bismuth-based quadruple therapy, by intention-to-treat (p = 0.018) and per-protocol (p = 0.088) analyses, respectively. Adverse events/intolerability were described in 12/82 patients in the OMM group and 18/78 patients in the OBMT group. Compliance with treatment was 92.7% in the OMM group and 83.3% in the OBMT group.

CONCLUSION

Moxifloxacin-based triple therapy is a highly effective second-line eradication treatment in H. pylori infection. Because of its high levels of safety and tolerability, this protocol represents an adequate alternative to the standard bismuth-based quadruple therapy.

Prevalence of antimicrobial resistance in Helicobacter pylori isolates in Taiwan in relation to consumption of antimicrobial agents

During 1998-2004, a total of 218 Helicobacter pylori isolates were obtained from patients who were randomised to receive one of the following regimens in a medical centre in Taiwan: lansoprazole, amoxicillin and clarithromycin (LAC) therapy; or lansoprazole, metronidazole and clarithromycin (LMC) therapy. In the LMC group, resistance rates for metronidazole and clarithromycin reduced from 48.6% (1998-2000) to 20.4% (2001-2004) (P<0.05) and from 13.5% to 6.3% (P<0.05), respectively. Analysis of annual antimicrobial consumption found that metronidazole use was slowly decreased both in the total population and in gastrointestinal disease patients. The per-protocol analysis revealed a higher eradication rate for patients using LMC therapy in 2001-2004 (82.6% vs. 75.0%), whilst there was similar efficacy for LAC therapy (84.8% vs. 84.2%). This observation suggests an effective programme to control H. pylori antibiotic resistance and hence elevate its cure rate.

Efficacy of levofloxacin-based rescue therapy for Helicobacter pylori infection after standard triple therapy: a randomized controlled trial

OBJECTIVES

This prospective study was designed to determine the efficacy of a levofloxacin-based rescue therapy for Helicobacter pylori infection after failure of standard triple therapies. We also surveyed the predictors of this rescue therapy.

PATIENTS AND METHODS

From June 2005 to March 2007, 1036 patients infected with H. pylori received standard triple regimens (proton pump inhibitor, clarithromycin and amoxicillin). H. pylori eradication was achieved in 855 (82.5%) subjects. One hundred and sixty-six eradication-failure patients were enrolled and randomly assigned to receive a 7 day eradication therapy with esomeprazole, bismuth subcitrate, tetracycline and metronidazole (EBTM) or esomeprazole, amoxicillin and levofloxacin (EAL). Follow-up endoscopy was done 16 weeks later to assess the treatment response. Patients' response, CYP2C19 genotypes and antibiotic resistances were also examined.

RESULTS

Intention-to-treat analysis revealed that both groups showed similar eradication rates [EBTM 63.9%; 95% confidence interval (CI): 53.6-74.2 and EAL 69.9%; 95% CI: 60.1-79.7] (P = 0.89). Per-protocol results were EBTM = 84.1% (95% CI: 75.1-93.1) and EAL = 75.3% (95% CI: 65.8-84.8) (P = 0.82). Both regimens had similar compliance (P = 0.32), but the EBTM group had more adverse events (P = 0.27). Logistic regression analysis showed that poor compliance, CYP2C19 homozygous extensive metabolizer genotype and levofloxacin resistance were important predictors for eradication failure.

CONCLUSIONS

The EAL regimen can achieve an efficacy similar to that of the standard EBTM therapy. It may be very useful in countries where bismuth salts are not available. Compliance, CYP2C19 genotype and resistances to antibiotics may influence the outcome of levofloxacin-based rescue therapy. It seems advisable to reserve levofloxacin for rescue treatment to avoid an increase in the resistance phenomenon.

Virulence factor genotypes of Helicobacter pylori affect cure rates of eradication therapy

The cure rates of Helicobacter pylori infection by using a combination of a proton pump inhibitor (PPI) and antimicrobial agents are mainly influenced by bacterial susceptibility to antimicrobial agents and the magnitude of acid inhibition during the treatment. Currently used empirical triple therapies do not reliably produce a > or =80% cure rate on an intention-to-treat basis. Therefore, tailored regimens based on relevant microbiological findings and pharmacogenomics are recommended for attaining an acceptable > or =95% cure rate. Recently, virulence factors of H. pylori, such as cagA and vacA, are reported to be major factors determining the cure rates. Individuals infected with strains with cagA-negative and vacA s2 genotypes have significantly increased risk of eradication failure of H. pylori infection. These virulence factors enhance gastric mucosal inflammation and are associated with the development of peptic ulcer and gastric cancer. H. pylori virulence factors induce proinflammatory cytokines, such as interleukin (IL)-1, IL-8, and tumor necrosis factor (TNF)- which influence mucosal inflammation and/or gastric acid secretion. When physicians select an H. pylori eradication regimen with an acceptable cure rate, they might need to consider H. pylori virulence factors, especially cagA and vacA.

Helicobacter pylori eradication improves gastric histology and decreases serum gastrin, pepsinogen I and pepsinogen II levels in patients with duodenal ulcer

BACKGROUND AND AIM

The aim of this study was to assess the gastric histopathology and serum gastrin-17 and pepsinogens profiles in patients with duodenal ulcer before and after Helicobacter pylori eradication in a population with a very high prevalence of H. pylori. At the same time we assessed the role of H. pylori density on these variables.

METHODS

Eighty Caucasian patients with H. pylori-associated duodenal ulcer before treatment and 1 year after randomized eradication were studied. Among patients with unsuccessful eradication two groups were distinguished according to the data obtained after treatment: the group with negative rapid urease test and decreased bacterial density according to morphological score (partial elimination group); the group with positive rapid urease test and high bacterial density (failed eradication group).

RESULTS

One year after successful eradication, serum levels of gastrin-17, pepsinogen I and pepsinogen II decreased. Similar changes of serum pepsinogen I and pepsinogen II levels were observed in patients with partial elimination of H. pylori infection. In the group with successful eradication, inflammation, activity, atrophy and number of lymphoid follicles in the antral mucosa fell. In the group with partial elimination, antral mucosa activity and H. pylori score reduced. Other morphological changes were statistically non-significant.

CONCLUSION

Patients with duodenal ulcer after successful eradication have improvement of morphological and functional characteristics of gastric mucosa.

“Rescue” regimens after Helicobacter pylori treatment failure

Helicobacter pylori (H pylori) infection is the main cause of gastritis, gastroduodenal ulcer disease, and gastric cancer. After more than 20 years of experience in H pylori treatment, in my opinion, the ideal regimen to treat this infection is still to be found. Currently, apart from having to know first-line eradication regimens well, we must also be prepared to face treatment failures. Therefore, in designing a treatment strategy we should not focus on the results of primary therapy alone, but also on the final (overall) eradication rate. The choice of a “rescue” treatment depends on which treatment is used initially. If a clarithromycin-based regimen was used initially, a subsequent metronidazole-based treatment (quadruple therapy) may be used afterwards, and then a levofloxacin-based combination would be a third “rescue” option. Alternatively, it has recently been suggested that levofloxacin-based rescue therapy constitutes an encouraging second-line strategy, representing an alternative to quadruple therapy in patients with previous PPI-clarithromycin-amoxicillin failure, with the advantage of efficacy, simplicity and safety. In this case, a quadruple regimen may be reserved as a third-line rescue option. Finally, rifabutin-based rescue therapy constitutes an encouraging empirical fourth-line strategy after multiple previous eradication failures with key antibiotics such as amoxicillin, clarithromycin, metronidazole, tetracycline, and levofloxacin. Even after two consecutive failures, several studies have demonstrated that H pylori eradication can finally be achieved in almost all patients if several rescue therapies are consecutively given. Therefore, the attitude in H pylori eradication therapy failure, even after two or more unsuccessful attempts, should be to fight and not to surrender.

Failure of first-line eradication treatment significantly increases prevalence of antimicrobial-resistant Helicobacter pylori clinical isolates

OBJECTIVES

Helicobacter pylori infection is a major health problem worldwide, and effective eradication of the infection is mandatory. The efficacy of recommended eradication regimens is approximately 70%. To avoid treatment failure and the consequent development of secondary resistance(s), it is important to choose the most appropriate first-line treatment regimen. This choice should also be made based on the knowledge of the antimicrobial resistance peculiar to a given geographical area. We evaluated the prevalence of antimicrobial-resistant H pylori strains isolated from naive patients and from patients with previous unsuccessful treatments.

METHODS

This study examined 109 H pylori-infected subjects (Group 1) who had never received an eradication treatment and 104 H pylori-infected subjects (Group 2) who had failed one or more eradication treatments. Resistance to amoxicillin (AMO), tetracycline (TET), clarithromycin (CLA), metronidazole (MET) and levofloxacin (LEV) was determined using the epsilometer test. The significance of differences was evaluated by the chi2 test.

RESULTS

The prevalence of antimicrobial resistance was 0% versus 3.1% to AMO, 0% versus 2% to TET, 27% versus 41.3% to MET (p<0.05), 18% versus 45.8% to CLA (p<0.05) and 3% versus 14.6% to LEV (p<0.05) in Group 1 vs Group 2, respectively. In Group 2, there was an increased prevalence of H pylori strains resistant to multiple antimicrobials.

CONCLUSIONS

This study confirms the high prevalence of H pylori strains resistant to CLA and MET, and indicates that unsuccessful treatments significantly increase resistance. Choosing eradication regimens other than standard triple therapy as a first-line therapy should be advisable in areas with high primary antimicrobial resistance prevalence.

The effects of probiotics on PPI-triple therapy for Helicobacter pylori eradication

BACKGROUND

This study was performed to evaluate whether the addition of probiotics to proton pump inhibitor (PPI)-based triple therapy increases the likelihood of successful Helicobacter pylori eradication.

MATERIALS AND METHODS

Three hundred and forty-seven H. pylori-infected patients were randomized into a triple-plus-yogurt group (yogurt group, n = 168) or a triple-only group (control group, n = 179). Triple therapy consisted of PPI b.i.d., clarithromycin 500 mg b.i.d., and amoxicillin 1 g b.i.d. for 7 days. Yogurt group received triple therapy for 1 week and one bottle of Will yogurt per day for at 3 weeks, starting on the first day of triple therapy. Will yogurt (a Korean brand) contains Lactobacillus acidophilus HY2177, Lactobacillus casei HY2743, Bifidobacterium longum HY8001, and Streptococcus thermophilus B-1. (13)C-urea breath test was performed at least 4 weeks after completion of triple therapy. Eradication rates, compliances, and adverse events were compared.

RESULTS

By intention-to treat analysis the H. pylori eradication rates in the yogurt group 79.2% (133 of 168) was similar to that in the control group 72.1% (129 of 179) (p = .124). However, by per-protocol (PP) analysis, the eradication rate in the yogurt group, 87.5% (133 of 152) was higher than that in the control group, 78.7% (129 of 164) (p = .037). Common adverse events were metallic taste (11.8%) and diarrhea (8.6%). The frequency of adverse effects in the yogurt group 41.1% (69/168) were higher than in the control group, 26.3% (47 of 179) (p = .003). However, most adverse events were mild to moderate in intensity, and the severities of adverse effects were similar in both groups (p = .401).

CONCLUSIONS

The addition of Will yogurt to triple therapy did not reduce the side-effects of triple therapy. But it increased the H. pylori eradication rate by PP analysis, encouraging more research in this field.

Helicobacter pylori eradication therapy: indications, efficacy and safety

BACKGROUND

Helicobacter pylori infects up to half of the world's population. It remains the major cause of peptic ulcer disease and is recognised as a carcinogen for its role in gastric carcinogenesis. Successful eradication of the bacteria is associated with improved health outcomes including fewer dyspeptic symptoms, reduced peptic ulcer recurrence and rebleeding, reduced peptic ulcer risk with NSAIDs and as a cure for low-grade gastric MALT lymphoma. The risk of gastric cancer is reduced in those without premalignant mucosal abnormalities at the time of eradication.

OBJECTIVE

This review outlines the current indications and options for therapy of H. pylori with particular reference to drug-induced adverse events associated with treatment.

METHODS

The indications for H. pylori eradication are evidence-based and in accordance with recent consensus statements and recommendations. The eradication treatment is based on numerous clinical trials and meta-analyses.

RESULTS/CONCLUSION

Eradication therapy, in general, is safe and well tolerated. Antibiotic therapy may be associated with significant drug adverse reactions, especially gastrointestinal symptoms.

Quadruple rescue therapy for Helicobacter pylori infection after two treatment failures

BACKGROUND

A standard third-line therapy for Helicobacter pylori infection is lacking, and antimicrobial sensitivity data for patients who failed eradication therapy are often unavailable in clinical practice. We therefore designed the prospective study to assess the efficacy of levofloxacin, amoxicillin, bismuth and rabeprazole quadruple therapy as a third-line treatment for H. pylori infection.

PATIENTS AND METHODS

From September 2005 to August 2007, 37 consecutive H. pylori-infected patients who had failed standard first-line and second-line treatments underwent a 10-day quadruple therapy comprising rabeprazole (20 mg b.i.d.), bismuth subcitrate (300 mg q.d.s.), amoxicillin (500 mg q.d.s.) and levofloxacin (500 mg o.d.). Follow-up endoscopy with rapid urease test, histological examination and culture was performed at 6 weeks after the end of treatment to evaluate the response to therapy.

RESULTS

Helicobacter pylori was successfully eradicated in 31 out of 37 patients (84% by both intention-to-treat analysis and per-protocol analysis). All patients complied with the eradication therapies, and only seven patients (19%) complained of mild-to-moderate adverse events. Amoxicillin- and levofloxacin-resistant strains were observed in 17% and 22% of the patients, respectively. There were no significant differences between H. pylori eradication rates and antibiotic resistances.

CONCLUSIONS

The 10-day levofloxacin- and amoxicillin-based quadruple therapy is well tolerated and achieves a high eradication rate as a third-line empirical treatment for H. pylori infection.

Second-line treatment for Helicobacter pylori infection: 10-day moxifloxacin-based triple therapy versus 2-week quadruple therapy

BACKGROUND AND AIM

The aim of this study was to test the efficacy of 10-day moxifloxacin-based triple therapy versus 2-week quadruple therapy for the second-line treatment of Helicobacter pylori infection.

METHODS

One hundred and ninety-two patients who had failed previous H. pylori eradication on standard triple therapy were randomized to one of two regimens: 1, moxifloxacin (400 mg q.d.), amoxicillin (1000 mg b.i.d.), and esomeprazole (20 mg b.i.d.) for 10 days (the 10MEA group), or 2, esomeprazole (20 mg b.i.d.), tripotassium dicitrate bismuthate (300 mg q.i.d.), metronidazole (500 mg t.i.d.), and tetracycline 500 mg (q.i.d.) for 14 days (the 14EBMT group). The eradication rates, drug compliances, and side-effect rates of these two regimens were compared.

RESULTS

Eradication rates by intention-to-treat and per-protocol analyses in the 10MEA and 14EMBT groups were 71.9% and 82.6%, and 71.7% and 90.5% (p = .973 and .321), respectively. The 10MEA group was significantly superior to the 14EMBT group in terms of side-effect rates (12.2% vs. 39.6%, p = .001), and discontinuation rates due to side-effects were lower in the 10MEA group than in the 14EMBT group (0.7% vs. 13.2%, p < .001). Moreover, compliance was higher in the 10MEA group (94.2% (131/139)) than in the 14EBMT group (83.0% (44/53)) (p = .014).

CONCLUSION

The 10-day moxifloxacin-based triple therapy was found to have a high eradication rate with few side-effects and good drug compliance. These findings suggest that this regimen is a safe and effective second-line treatment option for H. pylori infection in Korea.

Clarithromycin resistance, tumor necrosis factor alpha gene polymorphism and mucosal inflammation affect H. pylori eradication success

Several bacterial and host-related factors concur in causing Helicobacter pylori eradication failure. We ascertained the role of bacterial virulence genes (cagA, vacA), clarithromycin resistance [Cla(R), 23S ribosomal RNA (rRNA) mutations], host polymorphism of CYP2C19 (polyphosphoinositide, PPI, metabolism) and of the cytokines IL-1B-31C>T, IL-1RN VNTR, IFN-gamma+874A>T, TNF-alpha-1031T>C, TNF-alpha-857C>T, TNF-alpha-376G>A, TNF-alpha-308G>A, TNF-alpha-238G>A, IL-10-1082A>G, IL-10-819C>T, IL-10-592C>A, IL-12A+6686G>A, IL-12B+15485A>C. Two groups of H. pylori-infected and H. pylori-treated patients were retrospectively identified: 45 not eradicated and 57 eradicated. Treatment failure was significantly correlated with Cla(R) (all resistant strains in non-eradicated patients); with TNF-alpha-238, IL10-819, IL10-592, IL-12B+15485 single nucleotide polymorphism (SNP); with IL10 ATA/ATA haplotype; and with antral inflammatory grade. On considering Cla(S)-infected patients only, logistic regression analysis (eradication = dependent; TNF-alpha-238, IL12B + 15485 genotypes, IL10 ATA/ATA as present or absent, antral gastritis grade = covariates) confirmed as significantly correlated with eradication antral gastritis grade only (Exp(B) = 6.48; 95% CI, 1.2-35.01). In conclusion, the bacterial determinant causing triple therapy failure is clarithromycin resistant, being virulence genes not involved. The host related factors that favor eradication are those linked to inflammation: a higher inflammatory infiltrate in the mucosa, possibly favored by genotypes able to down regulate the anti-inflammatory cytokine response, enhance the chance of eradication success.

One-week versus two-week furazolidone-based quadruple therapy as the first-line treatment for Helicobacter pylori infection in Iran

BACKGROUND AND AIM

Furazolidone-based regimens for the eradication of Helicobacter pylori are low cost and effective although less tolerable. Our aim was to compare the efficacy and compliance of 1-week furazolidone-based quadruple therapy (furazolidone, amoxicillin, bismuth subcitrate, omeprazole; FABO) with 2-week quadruple therapy using the same drugs.

METHODS

One hundred and fifty-six consecutive patients with H. pylori related diseases were enrolled in our study. The patients were randomized into two groups of FABO1 and FABO2 groups receiving, 1 or 2 weeks' quadruple H. pylori eradication therapies, respectively, as follows: furazolidone (200 mg twice daily), amoxicillin (1 g twice daily), bismuth (240 mg twice daily) and omeprazole (20 mg twice daily). The chi(2) test was used to compare the efficacy of the therapies.

RESULTS

The per-protocol eradication rate in FABO1 and FABO2 groups were 56/66 (84.8%) and 57/69 (82.6%), respectively. The intention-to-treat eradication rate was 56/78 (71.8%) in FABO1 group and 57/78 (73.1%) in FABO2 group. There was not any significant statistical difference between two groups. A significant decrease in compliance in FABO2 group was seen.

CONCLUSION

This is an encouraging report showing a therapy with possible success in decreasing the duration of H. pylori infection as well as reaching the eradication rate of 80%.

American College of Gastroenterology guideline on the management of Helicobacter pylori infection

Helicobacter pylori (H. pylori) remains a prevalent, worldwide, chronic infection. Though the prevalence of this infection appears to be decreasing in many parts of the world, H. pylori remains an important factor linked to the development of peptic ulcer disease, gastric malignanc and dyspeptic symptoms. Whether to test for H. pylori in patients with functional dyspepsia, gastroesophageal reflux disease (GERD), patients taking nonsteroidal antiinflammatory drugs, with iron deficiency anemia, or who are at greater risk of developing gastric cancer remains controversial. H. pylori can be diagnosed by endoscopic or nonendoscopic methods. A variety of factors including the need for endoscopy, pretest probability of infection, local availability, and an understanding of the performance characteristics and cost of the individual tests influences choice of evaluation in a given patient. Testing to prove eradication should be performed in patients who receive treatment of H. pylori for peptic ulcer disease, individuals with persistent dyspeptic symptoms despite the test-and-treat strategy, those with H. pylori-associated MALT lymphoma, and individuals who have undergone resection of early gastric cancer. Recent studies suggest that eradication rates achieved by first-line treatment with a proton pump inhibitor (PPI), clarithromycin, and amoxicillin have decreased to 70-85%, in part due to increasing clarithromycin resistance. Eradication rates may also be lower with 7 versus 14-day regimens. Bismuth-containing quadruple regimens for 7-14 days are another first-line treatment option. Sequential therapy for 10 days has shown promise in Europe but requires validation in North America. The most commonly used salvage regimen in patients with persistent H. pylori is bismuth quadruple therapy. Recent data suggest that a PPI, levofloxacin, and amoxicillin for 10 days is more effective and better tolerated than bismuth quadruple therapy for persistent H. pylori infection, though this needs to be validated in the United States.

First-line triple therapy with levofloxacin for Helicobacter pylori eradication

BACKGROUND

At present, the efficacy of proton pump inhibitor-clarithromycin-amoxicillin regimen is relatively low.

AIM

To evaluate the efficacy and tolerability of a first-line triple clarithromycin-free regimen including ranitidine bismuth citrate, levofloxacin and amoxicillin.

DESIGN

Prospective study.

PATIENTS

Helicobacter pylori-positive patients complaining of dyspeptic symptoms referred for gastroscopy.

INTERVENTION

Levofloxacin (500 mg b.d.), amoxicillin (1 g b.d.) and ranitidine bismuth citrate (400 mg b.d.) was prescribed for 10 days.

OUTCOME

Eradication was confirmed by a (13)C-urea breath test 8 weeks after therapy. Compliance with therapy was determined by questioning and the recovery of empty envelopes of medications. Incidence of adverse effects was evaluated by means of a specific questionnaire.

RESULTS

Sixty-four patients were included (30% peptic ulcer, 70% functional dyspepsia). Almost all (97%) patients took all the medications correctly. Per-protocol and intention-to-treat eradication rates were 88.5% (95% CI =78-95%) and 84.4 (74-91%). Adverse effects were reported in 9.5% of the patients, mainly including diarrhoea (7.9%); none of them were severe.

CONCLUSION

This new 10-day levofloxacin-based combination represents an alternative to clarithromycin-based therapy, as it meets the criteria set for regimens used as primary H. pylori treatment: effectiveness (>80%), simplicity (twice-daily dosing and excellent compliance) and safety (low incidence of adverse effects).

Helicobacter pylori primary resistant strains over 11 years in French children

The yearly prevalence between 1994 and 2005 of primary resistance to amoxicillin, metronidazole, and clarithromycin of 377 Helicobacter pylori strains isolated from children was studied. All the H. pylori strains were susceptible to amoxicillin, 138/377 (36.7%) were resistant to metronidazole, 86/377 (22.8%) to clarithromycin, and 30/377 (7.9%) to both metronidazole and clarithromycin. Over the entire period, resistance to clarithromycin did not change, whereas metronidazole resistance decreased significantly from 43.3% (1994-1998) to 32% (1999-2005), P = 0.001.