A systematic review of Helicobacter pylori eradication therapy--the impact of antimicrobial resistance on eradication rates

Incidence of Helicobacter pylori infection and their clarithromycin-resistant strains in otitis media with effusion regarding phenotypic and genotypic studies

Helicobacter pylori (H. pylori) are pathogenic bacteria that infect a half of the human population, colonize gastric mucosa and can be found in gastric juice. Reflux of gastric juice has been suggested to be associated with glue ear in children. It has been suggested that tonsil and adenoid tissues are potential reservoirs of H. pylori infection. These observations raise the question as to whether H. pylori infection might have a role in otitis media with effusion (OME) in children. The objectives of this research were to evaluate the incidence and possible role of H. pylori in the pathogenesis of OME in children and to evaluate the clarithromycin-resistant strains. Molecular assessment was done to evaluate the culture results vs. molecular study. A total of 60 children, who were prone to ventilation tube insertion, adenoidectomy and/or tonsillectomy were included in the study. The control group consisted of 40 children who underwent adenoidectomy and/or tonsillectomy without the history of OME. Samples of the middle ear fluid and mucosa, adenoid tissue, tonsillar tissue and gastric lavage were cultured and underwent polymerase chain reaction (PCR) analysis then were assembled by using QIAxcel System as capillary electrophoresis for H. pylori detection. There was significant difference between the results of cultures and PCR (P < 0.05). Middle ear fluid culture was positive for H. pylori in 40% of the patients vs. 56.7% PCR results while middle ear mucosa culture was positive in 20% vs. 26.7% PCR results. Gastric lavage culture was positive in 46.6% of the patients and PCR was positive in 63.3% of the patients. Adenoid culture and PCR were positive in 56.3% for each, while tonsil culture was positive in 70% and PCR was positive in 90%. H. pylori presence in the gastric lavage, the tonsillar and adenoid tissues by culture and PCR was significantly more frequent in the study group compared to the control group. The minimum inhibitory concentration (MIC) values of clarithromycin-resistant isolates ranged from 1.5 to 8 μg/ml. This study showed the presence of H. pylori in around 50% of the patients with OME. PCR revealed its sensitivity than culture techniques. The incidence of clarithromycin resistance was found to be high among the isolates (39.6%).

Rescue Therapy for Helicobacter pylori Infection 2012

Helicobacter pylori infection is the main cause of gastritis, gastroduodenal ulcer disease, and gastric cancer. After 30 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. In designing a treatment strategy, we should not only 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 2nd-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 3rd-line "rescue" option. 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.

Randomised clinical trial: a comparative study of 10-day sequential therapy with 7-day standard triple therapy for Helicobacter pylori infection in naïve patients

BACKGROUND

The eradication rates following standard triple therapy for Helicobacter pylori infection are declining worldwide. Recent studies have shown that sequential therapy for H. pylori infection yields high cure rates.

AIM

To compare the efficacy and tolerability of a sequential regimen as first-line treatment of H. pylori infection with a standard triple regimen.

METHODS

A total of 348 naïve H. pylori-infected patients from six hospitals in Korea were assigned randomly to standard triple or sequential therapy groups. Standard triple therapy consisted of 20 mg of rabeprazole, 1 g of amoxicillin and 500 mg of clarithromycin, twice daily for 7 days. Sequential therapy consisted of a 5-day dual therapy (20 mg of rabeprazole and 1 g of amoxicillin, twice daily) followed by a 5-day triple therapy (20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily).

RESULTS

The intention-to-treat (ITT) and per-protocol (PP) eradication rates were 62.2% (95% CI 54.8-69.6%) and 76.0% (95% CI 68.5-83.5%) in the standard triple group, and 77.8% (95% CI 71.4-84.2%) and 87.9% (95% CI 82.3-93.5%) in the sequential group, respectively. The eradication rate was significantly higher in the sequential group compared with the standard triple group in both the ITT and PP populations (P = 0.002 and P = 0.013 respectively), whereas the incidence of adverse events was similar.

CONCLUSIONS

Ten-day sequential therapy is more effective and equally tolerated for eradication of H. pylori infection compared with standard triple therapy. Sequential therapy may have a role as first-line treatment for H. pylori infection.

[Helicobacter pylori eradication therapy in Korea]

Helicobacter pylori (H. pylori) is known to be associated with many gastrointestinal diseases including peptic ulcer. In Korea, eradication of H. pylori is recommended for peptic ulcer disease, low grade gastric mucosa-associated lymphoid tissue lymphoma, and early gastric cancer. Standard triple therapy using proton pump inhibitor, clarithromycin, and amoxicillin and bismuth-containing quadruple therapy have been the main first-line and second-line therapy for H. pylori in Korea. Although eradication rate of second-line quadruple therapy remains similar to that of the past, the success rate of eradication with triple therapy has decreased with increasing antimicrobial resistance to H. pylori. There is no standard third-line therapy, and some regimens that incorporate levofloxacin, moxifloxacin, and rifabutin can be used. New regimens such as sequential or concomitant therapy are suggested as alternative treatment for H. pylori. We need more well designed randomized controlled studies to choose proper treatment for H. pylori infection.

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.

Review article: non-bismuth quadruple (concomitant) therapy for eradication of Helicobater pylori

BACKGROUND

Traditional standard triple therapy for Helicobacter pylori infection (PPI-clarithromycin-amoxicillin) can easily be converted to non-bismuth quadruple (concomitant) therapy by the addition of a nitroimidazole twice daily.

AIM

To critically review evidence on the role of non-bismuth quadruple therapy (PPI-clarithromycin-amoxicillin-nitroimidazole) in the treatment of H. pylori infection.

METHODS

Bibliographical searches were performed in MEDLINE and relevant congresses.

RESULTS

The first randomised comparison of the non-bismuth quadruple therapy and the sequential (PPI-amoxicillin 5days plus PPI-clarithromycin-nitroimidazole 5days) regimens recently concluded that both were similar in terms of efficacy and safety and that the sequential administration protocol may be unnecessarily complex. Several randomised controlled trials (and one meta-analysis) have demonstrated that non-bismuth quadruple therapy is more effective than and is equally well tolerated as standard triple therapy. A meta-analysis of 15 studies (1723 patients) revealed a mean H. pylori cure rate (intention-to-treat) of 90% for non-bismuth quadruple therapy. A tendency towards better results with longer treatments (7-10days vs. 3-5days) has been observed, so it seems reasonable to recommend the length of treatment by achieving maximal cure rates (10days). Clarithromycin resistance may reduce the efficacy of non-bismuth quadruple therapy, although the decrease in eradication rates seems to be far lower than in standard triple therapy. Experience with the non-bismuth quadruple therapy in patients with metronidazole-resistant strains is still very limited.

CONCLUSIONS

Non-bismuth quadruple (concomitant) therapy appears to be an effective, safe, and well-tolerated alternative to triple therapy and is less complex than sequential therapy. Therefore, this regimen appears well suited for use in settings where the efficacy of triple therapy is unacceptably low.

Efficacy of levofloxacin and rifaximin based quadruple therapy in Helicobacter pylori associated gastroduodenal disease: a double-blind, randomized controlled trial

The aim of this study was to evaluate the efficacy of levofloxacin and rifaximin based quadruple regimen as first-line treatment for Helicobacter pylori infection. A prospectively randomized, double-blinded, parallel group, comparative study was performed. Three hundred consecutive H. pylori positive patients were randomized to receive: omeprazole, amoxicillin, clarithromycin (OAC); omeprazole, amoxicillin, levofloxacin (OAL); and omeprazole, amoxicillin, levofloxacin, rifaximin (OAL-R). The eradication rates in the intention to treat (ITT) and per protocol (PP) analyses were: OAC, 77.8% and 85.6%; OAL, 65.3% and 73.6%; and OAL-R, 74.5% and 80.2%. The eradication rate achieved with OAC was higher than with OAL on the ITT (P = 0.05) and PP analysis (P = 0.04). OAL-R regimen was not inferior to OAC. The frequency of moderate to severe adverse effects was significantly higher in OAC treatment group. Especially, diarrhea was most common complaint, and there was a significantly low rate of moderate to severe diarrhea with the rifaximin containing regimen. In conclusion, the levofloxacin and rifaximin based regimen comes up to the standard triple therapy, but has a limited efficacy in a Korean cohort. The rifaximin containing regimen has a very high safety profile for H. pylori eradication therapy.

High Helicobacter pylori resistance to metronidazole but zero or low resistance to clarithromycin, levofloxacin, and other antibiotics in Malaysia

OBJECTIVE

Bacterial resistance to antibiotics is the single most important determinant of treatment success. The objective of this study was to determine the prevalence of Helicobacter pylori resistance to clarithromycin, amoxicillin, metronidazole, tetracycline, levofloxacin, rifabutin, and furazolidone in our local bacterial strains.

METHODS

Samples from consecutive ninety patients were obtained for culture and sensitivity testing. Resistance to individual antibiotics were tested using the E-test and MIC(90) read from the strips. Resistance to rifampicin and nitrofurantoin were used as a surrogate for rifabutin and furazolidine.

RESULTS

There was a high prevalence of resistance to metronidazole 68/90 (75.5%). No male (34/45 (75.5%) versus female (35/45 (77.7%) difference in frequency of metronidazole resistance was noted (p = 1.000). There was zero resistance (0) to clarithromycin, levofloxacin, amoxicillin, and nitrofurantoin/furazolidone. Resistance to rifampicin/rifabutin was for breakpoints of 1 and 4 μg/mL of 14.4 and 2.2% respectively.

CONCLUSIONS

Although there was high bacterial resistance to metronidazole, the absence of resistance particularly to the key antibiotics used in H. pylori eradication therapy: clarithromycin and levofloxacin is reassuring to note. Continued monitoring of antibiotic resistance should be carried out.

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.

Cholesterol enhances Helicobacter pylori resistance to antibiotics and LL-37

The human gastric pathogen Helicobacter pylori steals host cholesterol, modifies it by glycosylation, and incorporates the glycosylated cholesterol onto its surface via a cholesterol glucosyltransferase, encoded by cgt. The impact of cholesterol on H. pylori antimicrobial resistance is unknown. H. pylori strain 26695 was cultured in Ham's F12 chemically defined medium in the presence or absence of cholesterol. The two cultures were subjected to overnight incubations with serial 2-fold dilutions of 12 antibiotics, six antifungals, and seven antimicrobial peptides (including LL-37 cathelicidin and human alpha and beta defensins). Of 25 agents tested, cholesterol-grown H. pylori cells were substantially more resistant (over 100-fold) to nine agents than were H. pylori cells grown without cholesterol. These nine agents included eight antibiotics and LL-37. H. pylori was susceptible to the antifungal drug pimaricin regardless of cholesterol presence in the culture medium. A cgt mutant retained cholesterol-dependent resistance to most antimicrobials but displayed increased susceptibility to colistin, suggesting an involvement of lipid A. Mutation of lpxE, encoding lipid A1-phosphatase, led to loss of cholesterol-dependent resistance to polymyxin B and colistin but not other antimicrobials tested. The cgt mutant was severely attenuated in gerbils, indicating that glycosylation is essential in vivo. These findings suggest that cholesterol plays a vital role in virulence and contributes to the intrinsic antibiotic resistance of H. pylori.

Risk factors associated with Helicobacter pylori infection treatment failure in a high prevalence area

Triple therapy is commonly used for the treatment of Helicobacter pylori infection. We determined risk factors associated with its failure in compliant patients focusing on H. pylori density, virulence marker and 23S ribosomal RNA (rRNA) point mutations associated with clarithromycin resistance. H. pylori infection was diagnosed by 14C urea breath test (14C UBT) and rapid urease test or histology. Triple therapy with esomeprazole 20 mg b.i.d., amoxicillin 1 g b.i.d. and clarithromycin 500 mg b.i.d. was prescribed for 10 days. 14C UBT was repeated 4 weeks after treatment. In total, 111 patients [69 (62%) males] with a mean age of 46±16 years were enrolled. The mean age of treatment failure was 39±14 years compared to 48±16 years with eradication (P=0·002). Treatment failure was associated with younger mean age, point mutations in the 23S rRNA gene of H. pylori and vacA s1a and m1 when associated with cagA negativity.

Age-dependent eradication of Helicobacter pylori in Japanese patients

AIM: To determine the general risk factors affecting the failure rate of first-line eradication therapy in Japanese patients with Helicobacter pylori (H. pylori) infection.

METHODS: The present study enrolled 253 patients who had an H. pylori infection, underwent gastro-endoscopy, and were treated with H. pylori eradication therapy. Eradication therapy consisted of 30 mg lansoprazole plus 750 mg amoxicillin and 400 mg clarithromycin twice daily for 7 d. All of the patients underwent a ¹³C urea breath test at least 1 mo after the completion of eradication therapy. The current study investigated the independent factors associated with successful H. pylori eradication using a multiple logistic regression analysis.

RESULTS: The overall success rate in the patients was 85.8%. Among the general factors examined in the multivariate analyses, only having an age less than 50 years was found to be significantly associated with a poor response to H. pylori eradication. Moreover, side effects were the only clinical factors in the patients who were under 50 years of age that significantly influenced the poor response to H. pylori eradication.

CONCLUSION: H. pylori-positive elderly patients should undergo eradication therapy. In addition, it is necessary to improve H. pylori eradication therapy in younger patients.

First-line eradication of Helicobacter pylori: Are the standard triple therapies obsolete? A different perspective

Studies concerning the eradication of Helicobacter pylori have resulted in a proliferation of meta-analyses. To date, there are 303 meta-analyses cited in PubMed, 113 dealing with the therapy of the infection. A chronological analysis of the results of meta-analyses performed between 1998 and 2010 shows that first-line standard triple therapies achieved eradication rates on an intention-to-treat basis of around 80%; prolonging treatment to 14, but not 10 d should improve the results. The proton pump inhibitors have a similar efficiency, and giving a double dose is more efficient than the standard doses of these drugs. Triple and quadruple therapies proved to be equivalent. Based on meta-analytical data, the decrease in efficiency over time cannot be substantiated: eradication rates < 80% followed from the introduction of triple therapies. As alternatives, ranitidine bismuth citrate-, levofloxacin- or furazolidone-based therapies were shown to obtain the same eradication rates as standard triple regimens. Sequential therapies and quadruple non-bismuth-based therapies were superior to standard triple therapies but their use is limited to certain countries. In the author’s opinion, and from a meta-analytical viewpoint, standard triple therapies cannot yet be considered obsolete. Furthermore, non-inferiority trials are proposed for the future, including assessment of local contemporary antimicrobial resistance profiles and the CagA and CYP2C19 status of the enrolled patients.

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.

Sequential therapy for Helicobacter pylori eradication: a critical review

BACKGROUND

Alternative treatment regimens for standard triple therapy are urgently needed.

AIM

To critically review the evidence on the role of "sequential" regimen for the treatment of Helicobacter pylori infection.

METHODS

Bibliographical searches were performed in MEDLINE and international congresses.

RESULTS

Several pooled-data analyses and meta-analyses have demonstrated that sequential regimen is more effective than standard triple therapy. Sequential therapy is not affected by bacterial (CagA status, infection density) and host factors (underlying disease, smoking). Clarithromycin resistance seems to be the only factor reducing their efficacy. However, even in these patients, an acceptable >75% eradication rate can be achieved. Unfortunately, almost all the studies have been performed in Italy. Whether it is necessary to provide the drugs sequentially or if the 4 components of sequential therapy can be given concurrently is unclear. Nonbismuth quadruple therapy seems to be an effective and safe alternative to triple therapy and is less complex than sequential therapy.

CONCLUSIONS

Sequential therapy is a novel promising treatment approach that deserves consideration as a treatment strategy for H. pylori infection. However, further robust assessment across a much broader range of patients is required before sequential therapy could supplant existing treatment regimens and be generally recommended in clinical practice.

Clarithromycin resistance and point mutations in the 23S rRNA gene in Helicobacter pylori isolates from Malaysia

OBJECTIVE

To determine the prevalence of primary clarithromycin resistance amongst Helicobacter pylori (H. pylori) strains in Malaysian patients with gastroduodenal diseases, by using restriction fragment length polymorphism (RFLP) in domain V of 23S rRNA.

METHODS

Gastric biopsies were obtained from H. pylori positive patients undergoing gastroscopy. DNA extraction was followed by PCR amplification using the primers Hp23-1 and Hp23-2 flanking a region of 425bp within the bacterial 23S rRNA peptidyltranferase (Hp23S fragment). Analysis of the 23S rRNA gene mutations is based on the generation of restriction sites for two restriction enzymes: BbsI and BsaI, which correspond to the base substitutions characteristic of clarithromycin resistance from A to G at positions 2142 and 2143, respectively.

RESULTS

Gastric biopsy samples were obtained from 107 patients. A fragment of size 425bp corresponding to that expected from amplification of domain V of 23S rRNA was PCR-amplified from only 105 samples. The amplicon was subsequently subjected to restriction by BbsI and BsaI. Only 1 sample (0.95%) had the BbsI mutation (base substitution at A2142G) and 2 samples (1.90%) the BsaI mutation (base substitution at A2143G). Thus 3 of 105 (2.9%) samples harbored clarithromycin resistant strains.

CONCLUSION

In our experience, PCR-RFLP is a rapid and precise method to detect the resistance of H. pylori to clarithromycin. Using this method, a low prevalence of clarithromycin resistance was detected in our local Malaysian strains. This augurs well for the continued use of clarithromycin as a first line drug in the treatment and eradication of H. pylori infection.

Ten and eight-day sequential therapy in comparison to standard triple therapy for eradicating Helicobacter pylori infection: a randomized controlled study on efficacy and tolerability

BACKGROUND

Sequential therapy (SQT) is effective in the eradication of Helicobacter pylori and could become an alternative to standard triple therapy (STT).

AIM

To compare the efficacy and tolerability of SQT, for either 8 or 10 days, with a 7-day STT.

METHODS

A total of 270 naive H. pylori-positive patients were randomized to receive: SQT for 8 days (SQT-8, n=90) or 10 days (SQT-10, n=90) including esomeprazole 20 mg twice daily (bid) associated with amoxicillin 1000 mg bid (early 4 and 5 d, respectively), followed by esomeprazole 20 mg bid associated with clarithromycin 500 mg bid plus tinidazole 500 mg bid (last 4 and 5 d, respectively); STT (n=90) including esomeprazole 20 mg bid plus amoxicillin 1000 mg bid and clarithromycin 500 mg bid for 7 days. Tolerability was assessed by scoring the severity of symptoms.

RESULTS

Eradication rates after SQT-8 and SQT-10 were higher than that of after STT at both intention-to-treat (83% and 86% vs. 66%, P<0.02) and per-protocol analysis (90% and 88% vs. 75%, P<0.05), whereas no difference was found between the 2 SQTs.

CONCLUSIONS

This study shows that SQT, for 8 or 10 days, is well tolerated and highly effective in H. pylori eradication and could represent a valid alternative to STT. Further studies, with more power, on larger populations and from other countries are necessary to validate the present findings.

Helicobacter pylori first-line treatment and rescue option containing levofloxacin in patients allergic to penicillin

AIM

To assess the efficacy and tolerability of Helicobacter pylori first-line treatment (omeprazole-clarithromycin-metronidazole) and second-line rescue option (omeprazole-clarithromycin-levofloxacin) in patients allergic to penicillin.

PATIENTS

Prospective multicenter study including consecutive patients allergic to penicillin. Therapy regimens: First-line treatment (50 patients): Omeprazole (20mg b.i.d.), clarithromycin (500 mg b.i.d.) and metronidazole (500 mg b.i.d.) for 7 days. Second-line treatment (15 therapy failures out of the aforementioned 50 patients): Omeprazole (20mg b.i.d.), clarithromycin (500 mg b.i.d.) and levofloxacin (500 mg b.i.d.) for 10 days.

OUTCOME VARIABLE

Negative (13)C-urea breath test 8 weeks after completion of treatment.

RESULTS

(1) First-line treatment (omeprazole-clarithromycin-metronidazole): Per-protocol and intention-to-treat eradication rates were 55% (27/49; 95%CI=40-70%) and 54% (27/50; 95%CI=39-69%). Compliance with treatment and follow-up was complete in 98% of cases (one patient was not compliant due to nausea). Adverse events were reported in 5 patients (10%): 4 nausea, 1 diarrhoea. (2) Second-line treatment (omeprazole-clarithromycin-levofloxacin): Per-protocol and intention-to-treat eradication rates were both 73% (11/15; 95%CI=45-92%). Compliance with treatment and follow-up was complete in all the cases. Adverse events were reported in 4 patients (20%), which did not prevent the completion of treatment: Mild nausea (2 patients), and vomiting and myalgias/arthralgias (1 patient).

CONCLUSION

In H. pylori infected patients allergic to penicillin, the generally recommended first-line treatment with omeprazole, clarithromycin and metronidazole has low efficacy for curing the infection. On the other hand, a levofloxacin-containing regimen (together with omeprazole and clarithromycin) represents an encouraging second-line alternative in the presence of penicillin allergy.

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.

Is antimicrobial susceptibility testing necessary before first-line treatment for Helicobacter pylori infection? Meta-analysis of randomized controlled trials

BACKGROUND

With the wide use of antibiotics, antibiotic-resistant Helicobacter pylori strains are becoming increasingly prevalent. It has been hypothesized that culture-guided therapy might help to increase treatment success. But the effects and the costs still remain controversial.

AIMS

To systematically review the efficacy and the cost of culture-guided triple therapy, compared to standard triple regimen for first-line treatment of Helicobacter pylori infection.

METHODS

A search of the Cochrane Library, PubMed, EMBASE, Science Citation Index Expanded and CBM was performed. Randomized controlled trials comparing culture-guided triple therapy to standard triple therapy in the first-line treatment of Helicobacter pylori infection were selected for meta-analysis. Relative risk was used as a measure of the effect of two regimens mentioned above with a fixed-effects model using the methods of DerSimonian and Laird.

RESULTS

Five randomized controlled trials totaling 701 patients were included. The meta-analysis showed that culture-guided triple therapy was superior referring to a higher eradication rate from intention-to-treat analyses (RR, 0.84; 95% CI,0.77, 0.90; p<0.00001) and a lower overall cost.

CONCLUSION

Culture-guided triple therapy was more effective than standard triple therapy for first-line treatment of Helicobacter pylori infection. Based on the only paper focused on the overall cost, the culture-guided triple therapy was also more cost saving. Antimicrobial susceptibility testing is necessary before first-line treatment for Helicobacter pylori infection.

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.

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.

Efficacy of a new therapeutic regimen versus two routinely prescribed treatments for eradication of Helicobacter pylori: a randomized, double-blind study of doxycycline, co-amoxiclav, and omeprazole in Iranian patients

This study compared a new regimen (group A: doxycycline, co-amoxiclav, omeprazole) and two routinely prescribed regimens (group B: amoxicillin, omeprazole, furazolidone, bismuth; group C: amoxicillin, clarithromycin, omeprazole) to find an acceptable first-line treatment option for Helicobacter pylori. The study population consisted of 189 patients who referred to our clinic to undergo endoscopy due to ulcer-like dyspepsia. The H. pylori eradication rate was 68% in group A, 56% in group B, and 70% in group C according to per-control analysis. There was no statistically significant difference in H. pylori eradication between groups A and B (P = 0.187), groups A and C (P = 0.857), and groups B and C (P = 0.15). In conclusion, although none of the three eradication regimens can be recommended as a first-line eradication treatment, the new regimen is at least as effective and probably better tolerated than the two routinely applied regimens.

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.

The efficacy of ranitidine bismuth citrate, amoxicillin and doxycycline or tetracycline regimens as a first line treatment for Helicobacter pylori eradication

BACKGROUND

The eradication rates of Helicobacter pylori (H. pylori) clearly decreased with standard PPI-based triple therapies.

AIM

To assess the efficacy of two different triple therapies consisting of ranitidine bismuth citrate-amoxicillin-doxycycline and ranitidine bismuth citrate-amoxicillin-tetracycline combinations as a first line treatment option.

METHODS

One hundred and fifteen consecutive dyspeptic patients in whom H. pylori infection was diagnosed for the first time were enrolled in this study. The patients were randomized into two groups. Group 1 (n=57) was assigned to receive a 14-day triple therapy consisting of ranitidine bismuth citrate 400 mg (b.i.d.), amoxicillin 1 g (b.i.d) and doxycycline 100 mg (b.i.d.). Group 2 (n=58) was assigned to receive a 14-day triple therapy consisting of ranitidine bismuth citrate 400 mg (b.i.d.), amoxicillin 1 g (b.i.d.) and tetracycline 500 mg (q.i.d.).

RESULTS

The eradication was achieved in 45.7% (21/46) and 40.8% (20/49) of the patients in group 1 and group 2, according to per protocol analysis. The intention-to-treat eradication rates were 36.8% (21/57) and 34.5% (20/58) in group 1 and group 2, respectively.

CONCLUSIONS

Two-week therapy with neither ranitidine bismuth citrate-amoxicillin-doxycycline nor ranitidine bismuth citrate-amoxicillin-tetracycline is adequately effective for H. pylori eradication as a first line therapy.

Moxifloxacin-based triple therapy versus clarithromycin-based triple therapy for first-line treatment of Helicobacter pylori infection: a meta-analysis of randomized controlled trials

BACKGROUND

Moxifloxacin-based triple therapy has been suggested as an alternative first line therapy to clarithromycin-based triple therapy for Helicobacter pylori infection.

AIMS

To systematically review the efficacy and tolerance of moxifloxacin-based triple therapy, and to conduct a meta-analysis of studies comparing this regimen with clarithromycin-based triple therapy.

METHODS

A search of The Cochrane Library, PUBMED, EMBASE, EBM Review databases, Science Citation Index Expanded, and CMB (Chinese Biomedical Literature Database) was performed. Randomized controlled trials comparing moxifloxacin-based triple therapy to gold standard triple therapy in the first-line treatment of Helicobacter pylori infection were selected for meta-analysis. Relative risk was used as a measure of the effect of the two above-mentioned regimens with a fixed-effects model using the methods of DerSimonian and Laird.

RESULTS

Four randomized controlled trials totaling 772 patients were included. The meta-analysis showed that the mean eradication rate was 84.1 (318/378) in the moxifloxacin-based triple therapy group and 73.6 (290/394) in the clarithromycin-based triple therapy group; there was statistical significance between the two groups (RR, 1.13; 95% CI, 1.01, 1.27; P=0.04). There were no statistically significant difference in the overall side effects (RR, 0.61; 95% CI, 0.25, 1.48; P<0.28).

CONCLUSIONS

Moxifloxacin-based triple therapy is more effective and does not increase the incidence of overall side effects compared to clarithromycin-based triple therapy in the treatment of H. pylori infection.

H. pylori treatment: new wine in old bottles?

Treatment of Helicobacter pylori infection has become a problem in many clinical settings. Eradication rates are at the lowest levels seen in the past decade and are likely to fall further as antimicrobial resistance becomes more prevalent worldwide. Culture of H. pylori and antimicrobial sensitivity testing is still not generally available; therefore treatment strategies that are selected based on information that is specific to the individual patient are often not possible. Current strategies for treatment in most Western countries consist of initial therapy with a combination of a proton pump inhibitor therapy with amoxicillin and clarithromycin, with quadruple therapy reserved for failures. Sequential therapy is an attractive new alternative for initial treatment and may offer an alternative to conventional therapies. The choice of initial therapy is in a state of flux and this article will discuss alternative treatment strategies that clinicians may use in this difficult environment.

Effect of CYP2C19 genetic polymorphisms on the efficacy of proton pump inhibitor-based triple therapy for Helicobacter pylori eradication: a meta-analysis

OBJECTIVE

CYP2C19 polymorphisms have been inconsistently reported to associate with the efficacy of proton pump inhibitor (PPI)-based triple therapies for eradicating Helicobacter pylori infection. The aim of this meta-analysis was to determine whether CYP2C19 polymorphism affect H. pylori eradication rates obtained with first-line PPI-based triple therapies.

METHODS

A systematic literature search was conducted up to July 2007 using Medline, PubMed, EMBase, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Science, CNKI (Chinese), and Wanfang (Chinese) digital database. MeSH terms and keywords included proton pump inhibitor, omeprazole, lansoprazole, rabeprazole, pantoprazole, or esomeprazole, cytochrome P4502C19 or CYP2C19, and Helicobacter pylori or H. pylori. Twenty articles met the inclusion criteria, and were included in the meta-analysis by using Review Manager 4.2.8.

RESULTS

Eradication rates were significantly different between poor metabolizers (PM) and heterozygous extensive metabolizers (HetEM) (odds ratio (OR) = 1.73, p = .002) and between PM and homozygous extensive metabolizers (HomEM) (OR = 2.79, p < .0001). Moreover, eradication rates were also significant difference between HetEM and HomEM (OR = 2.00, p < .0001). Triple omeprazole and lansoprazole therapies achieved higher H. pylori eradication rates in PM than in HomEM (OR = 4.28, p = .0005 for omeprazole and OR = 3.06, p = .001 for lansoprazole), and higher in HetEM than those in HomEM (OR = 3.22, p < .0001 for omeprazole and OR = 1.95, p = .040 for lansoprazole). Rabeprazole therapies had no significant effect on H. pylori eradication rates (between PM and HomEM, OR = 1.35, p = .610 and between HetEM and HomEM, OR = 1.57, p = .190). No significant difference in H. pylori eradication rates between PM and HetEM was observed in the three individual PPI therapies.

CONCLUSION

The efficacy of omeprazole- and lansoprazole-based first-line triple therapies at the standard doses is dependent on CYP2C19 genotype status, which appears not to affect the efficacy of the regimens including rabeprazole.

Moxifloxacine plus amoxicillin and ranitidine bismuth citrate or esomeprazole triple therapies for Helicobacter pylori infection

Up to 20% of patients, or even more, will fail to obtain eradication after a standard triple therapy. The aim of this study is to evaluate the efficacy of moxifloxacine-containing regimens in the first-line treatment of Helicobacter pylori. One hundred and twenty H. pylori-positive patients were randomized into four groups to receive one of the following 14-day treatments: ranitidine bismuth citrate (RBC) 400 mg b.d. plus amoxicillin 1 g b.d. and clarithromycin 500 mg b.d. (RAC group, n = 30); RBC 400 mg b.d. plus moxifloxacine 400 mg o.d. and amoxicillin 1,000 mg b.d. (RAM group, n = 30); esomeprazole 40 mg b.d. plus amoxicillin 1,000 mg b.d. plus clarithromycin 500 mg b.d. (EAC group, n = 30); and esomeprazole 40 mg b.d. plus amoxicillin 1,000 mg b.d. plus moxifloxacine 400 mg o.d. (EAM group, n = 30). Eradication was assessed by (13)C urea breath test 8 weeks after therapy. Per-protocol and intention-to-treat eradication was achieved in 23 out of 30 patients (76.7%, 95% confidence interval [CI]: 61-92) in the RAC group, in 20 patients (66.7%, 95% CI: 49-84) in the RAM group, in 16 patients in the EAM group (53.3%, 95% CI: 34-71), and in 19 patients in the EAC group (63.3%, 95% CI: 54-72). Mild or moderate side-effects were significantly more common in the EAM group (70%) compared to the RAC (36.6%), RAM (43.3%), and EAC (56.6%) groups (P = 0.03). From our results, we conclude that moxifloxacine-containing triple therapies have neither eradication nor compliance advantages over standard triple therapies. Further studies with new antibiotic associations are needed for the better eradication of H. pylori in developing regions of the world.

Quadruple therapy with furazolidone for retreatment in patients with peptic ulcer disease

AIM: To establish the efficacy and safety of a 7-d therapeutic regimen using omeprazole, bismuth subcitrate, furazolidone and amoxicillin in patients with peptic ulcer disease who had been previously treated with other therapeutic regimens without success.

METHODS: Open cohort study which included patients with peptic ulcer who had previously been treated unsuccessfully with one or more eradication regimens. The therapeutic regimen consisted of 20 mg omeprazole, 240 mg colloidal bismuth subcitrate, 1000 mg amoxicillin, and 200 mg furazolidone, taken twice a day for 7 d. Patients were considered as eradicated when samples taken from the gastric antrum and corpus 12 wk after the end of treatment were negative for Helicobacter pylori (H pylori) (rapid urease test and histology). Safety was determined by the presence of adverse effects.

RESULTS: Fifty-one patients were enrolled. The eradication rate was 68.8% (31/45). Adverse effects were reported by 31.4% of the patients, and these were usually considered to be slight or moderate in the majority of the cases. Three patients had to withdraw from the treatment due to the presence of severe adverse effects.

CONCLUSION: The association of bismuth, furazolidone, amoxicillin and a proton-pump inhibitor is a valuable alternative for patients who failed to respond to other eradication regimens. It is an effective, cheap and safe option for salvage therapy of positive patients.

“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.

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.

High-resolution structure of the antibiotic resistance protein NimA from Deinococcus radiodurans

Many anaerobic human pathogenic bacteria are treated using 5-nitroimidazole-based (5-Ni) antibiotics, a class of inactive prodrugs that contain a nitro group. The nitro group must be activated in an anaerobic one-electron reduction and is therefore dependent on the redox system in the target cells. Antibiotic resistance towards 5-Ni drugs is found to be related to the nim genes (nimA, nimB, nimC, nimD, nimE and nimF), which are proposed to encode a reductase that is responsible for converting the nitro group of the antibiotic into a nonbactericidal amine. A mechanism for the Nim enzyme has been proposed in which two-electron reduction of the nitro group leads to the generation of nontoxic derivatives and confers resistance against these antibiotics. The cofactor was found to be important in the mechanism and was found to be covalently linked to the reactive His71. In this paper, the 1.2 A atomic resolution crystal structure of the 5-nitroimidazole antibiotic resistance protein NimA from Deinococcus radiodurans (DrNimA) is presented. A planar cofactor is clearly visible and well defined in the electron-density map adjacent to His71, the identification of the cofactor and its properties are discussed.

Quadruplex real-time PCR assay using allele-specific scorpion primers for detection of mutations conferring clarithromycin resistance to Helicobacter pylori

We developed a single-vessel multiplex real-time PCR assay that detects Helicobacter pylori infection and identified the four existing alleles of the 23S rRNA genes of H. pylori--the wild-type sequence and the three mutations conferring clarithromycin resistance--using allele-specific Scorpion primers directly on biopsy specimens. The Scorpion primers combine a primer and a probe in a single molecule and are able to distinguish single-nucleotide polymorphism. Fluorescent signals, produced when the probes are annealed, are read in four channels by a SmartCycler thermocycler. The assay was first applied successfully on 4 reference and 61 clinical strains. MICs of clarithromycin were determined by the Etest method. A perfect concordance was obtained between Etest and Scorpion PCR. Mixed populations were better detected by Scorpion PCR. We examined 259 biopsies from 229 patients by culture, PCR-restriction fragment length polymorphism (RFLP), and Scorpion PCR. One biopsy, positive for culture, exhibited inhibitors for both PCR-RFLP and Scorpion PCR. Twelve biopsies were positive for PCR-RFLP and Scorpion PCR but negative for culture with concordant determination of mutations in the 23S rRNA genes by the two PCR assays. Three biopsies were positive for Scorpion PCR only. Compared to culture, the sensitivity of Scorpion PCR was 98.3% and the specificity was 92.5%. The Scorpion PCR assay provides a highly accurate, rapid, and precise method for the detection and determination of mutations conferring clarithromycin resistance to H. pylori.

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.

Influence of Helicobacter pylori genotype on triple eradication therapy

BACKGROUND

The efficiency of Helicobacter pylori eradication varies geographically, as do many parameters that might affect therapeutic efficiency. The aims of this study were to investigate the relationship between different genotypes of H. pylori and bacterium-related histopathological lesions in patients with duodenal ulcer and to determine the effect of genotype on triple eradication therapy.

METHODS

Helicobacter pylori infections were analyzed in 78 duodenal ulcer patients. The cytotoxin-associated gene (cagA) and vacuolating cytotoxin gene (vacA) subtype status of cultured strains were studied by PCR. Histopathological findings were graded using a described grading system. The patients were treated with triple-therapy regimens consisting of a proton pump inhibitor and two antibiotics twice daily for 7 days. Endoscopy was repeated at 4 weeks post-therapy to monitor ulcer healing and H. pylori eradication.

RESULTS

The bacteria were genotyped from 66 patients, 57 of whom had H. pylori eradicated. The absence of cagA was associated with unsuccessful treatment. No difference was found with regard to vacA subtype between the successful and unsuccessful eradication groups. On histopathological examination, high H. pylori colonization density and intestinal metaplasia were associated with low eradication rate, while a high grade of neutrophil infiltration was associated with a significantly higher eradication rate.

CONCLUSIONS

The data confirm the importance of cagA positivity as a predictor of successful eradication. When high H. pylori colonization density and intestinal metaplasia are present, therapy appears to be less effective. Therefore, these histopathological features may be involved in an unsuccessful therapeutic outcome.

Efficacy and safety of faropenem in eradication therapy of Helicobacter pylori

AIMS

While triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin is the standard therapy for Helicobacter pylori eradication, it is ineffective against clarithromycin-resistant strains. To seek a better regimen for eradication therapy, we assessed the sensitivity of clinical strains seen in Japan to faropenem and then evaluated the efficacy and safety of eradication therapy containing this antibiotic.

METHODS

Minimum inhibitory concentrations (MICs) of faropenem were determined in 78 Japanese clinical H. pylori isolates using the agar dilution method. H. pylori-positive patients were consecutively assigned to a 7-day eradication therapy protocol with LAF (lansoprazole 60 mg/day, amoxicillin 2000 mg/day, and faropenem 600 mg/day), and then to a 14-day protocol. The outcomes of the therapies were assessed by (13)C-urea breath tests.

RESULTS

All 78 strains showed MICs of faropenem that were equal to or less than 0.2 microg/mL. The eradication rates according to intention-to-treat analyses were 46.5% with the 7-day therapy (n = 43) and 62.5% with the 14-day therapy (n = 32). No special measures were required to treat the adverse events observed in approximately one-third of the patients.

CONCLUSIONS

Faropenem was found to have good antimicrobial action against H. pylori in vitro. The 14-day LAF therapy successfully eradicated H. pylori in about two-thirds of the patients although the incidence of adverse events was high.

Levofloxacin-based triple therapy for Helicobacter pylori re-treatment: role of bacterial resistance

BACKGROUND

First-line Helicobacter pylori therapy fails in more than 20% of patients. Quadruple therapy is the suggested second-line therapy, but bismuth salts are not anymore available worldwide. This study aimed to assess the efficacy of a levofloxacin-amoxycillin triple therapy as a second-line treatment, and the role of primary levofloxacin resistance.

METHODS

Forty patients, in whom first treatment with either standard 10-day triple or sequential therapy had failed, received 10-day triple therapy with rabeprazole (20mg b.d.), levofloxacin (250mg b.d.), and amoxycillin (1g b.d.). Cure rates were evaluated by the (13)C-urea breath test. Primary levofloxacin resistance was detected by culture.

RESULTS

Bacterial culture was available in 33 (82.5%) out 40 patients, and primary levofloxacin resistance was detected in 10 (30.3%) patients. Overall, 33 of 40 patients accepted to participate in this study, and all returned for follow-up after therapy. Compliance to the therapy was safe except 1 patient only who stopped earlier the treatment due to side effects (oral candidiasis). H. pylori infection was eradicated in 24 patients, accounting for a 72.7% (95% CI: 57-88) eradication rate at both intention-to-treat and per protocol analyses. The eradication rate was higher in patients harbouring levofloxacin-susceptible than resistant strains (75% versus 33.3%; P=0.074).

CONCLUSIONS

The eradication rate achieved by a levofloxacin-based re-treatment seems to be decreasing, and its efficacy is reduced in presence of levofloxacin resistance.

Evaluation of networks of randomized trials

Randomized trials may be designed and interpreted as single experiments or they may be seen in the context of other similar or relevant evidence. The amount and complexity of available randomized evidence vary for different topics. Systematic reviews may be useful in identifying gaps in the existing randomized evidence, pointing to discrepancies between trials, and planning future trials. A new, promising, but also very much debated extension of systematic reviews, mixed treatment comparison (MTC) meta-analysis, has become increasingly popular recently. MTC meta-analysis may have value in interpreting the available randomized evidence from networks of trials and can rank many different treatments, going beyond focusing on simple pairwise-comparisons. Nevertheless, the evaluation of networks also presents special challenges and caveats. In this article, we review the statistical methodology for MTC meta-analysis. We discuss the concept of inconsistency and methods that have been proposed to evaluate it as well as the methodological gaps that remain. We introduce the concepts of network geometry and asymmetry, and propose metrics for the evaluation of the asymmetry. Finally, we discuss the implications of inconsistency, network geometry and asymmetry in informing the planning of future trials.

Comparison of 1- and 2-week pantoprazole-based triple therapies in clarithromycin-sensitive and resistant cases

BACKGROUND

The objectives of this prospective study were: (i) to compare the efficacy of 1-week with 2-week pantoprazole-based triple therapy and (ii) to evaluate the impact of clarithromycin resistance on Helicobacter pylori (H. pylori) eradication rates.

METHODS

Eighty dyspeptic patients were randomly allocated to two groups. The first group (PAC-1, n=40) received pantoprazole 40 mg, amoxicillin 1000 mg, and clarithromycin 500 mg twice a day for one week, and the second group (PAC-2, n=40) received the same regimen for two weeks. Endoscopy was repeated one month after the end of the treatment.

RESULTS

DNA extraction for clarithromycin resistance could not be performed in seven cases. Five cases were lost to follow-up. Clarithromycin resistance was found to be 44.1% (15/34) in the PAC-1 group and 58.8% (20/34) in the PAC-2 group (p>0.05). Eradication was achieved in 16 (PP: 47.1%, ITT: 44.4%) and 25 (PP:73.5%, ITT: 67.6%) patients in the PAC-1 and PAC-2 groups, respectively (p>0.05). H. pylori was eradicated in 4 of 15 (PP: 26.7%, ITT: 26.7%) clarithromycin-resistant patients in the PAC-1 group and in 12 of 20 (PP: 60%, ITT: 60%) clarithromycin-resistant patients in the PAC-2 group (p>0.05). Among the clarithromycin-sensitive ones, eradication was achieved in 12 of 19 (PP: 63.2%, ITT: 57.1%) patients in the PAC-1 group and in 13 of 14 (PP: 92.8%, ITT: 76.5%) patients in the PAC-2 group (p>0.05).

CONCLUSION

Although the 2-week regimen of pantoprazole-based triple therapy was effective for H. pylori eradication in clarithromycin-sensitive cases, highly effective H. pylori eradication protocols are needed for clarithromycin-resistant ones.