Two-week eradication regimen for metronidazole-resistant Helicobacter pylori

Efficacy of a "Rescue" Ciprofloxacin-Based Regimen for Eradication of Helicobacter pylori Infection after Treatment Failures

The aim of our study was to evaluate the efficacy and tolerability of a ciprofloxacin-based regimen for H. pylori eradication failures as an alternative to bismuth based quadruple therapy. Methods. Design: prospective single-center study. Patients in whom a first eradication trial with omeprazole/esomeprazole, clarithromycin plus amoxicillin or tinidazole/metronidazole had failed were included. H. pylori status: established by histology, rapide urease test and polymerase chain reaction. Intervention: esomeprazole 20 mg, ciprofloxacin 500 mg, and metronidazole 500 mg, administered together before breakfast and dinner for 10 days. Susceptibility testing was performed by the Epsilometer test. Ciprofloxacin resistance was defined as a MIC of ≥1 μg/mL. Eradication was established by a negative 13C-UBT and 4–6 weeks post-therapy. Efficacy and side effects were determined. Results. 34 patients were enrolled, 32 completed the study. Compliance was excellent (100%). Side effects were mild. Ciprofloxacin-based therapy cured 65% (22/34) of patients by intention to treat and 69% (22/32) per protocol analysis. The prevalence of ciprofloxacin resistance was 8%. Conclusions. The effectiveness of ciprofloxacin-based therapy was greatly reduced despite the high prevalence of ciprofloxacin sensitive H. pylori strains. Bismuth based quadruple therapy still remain the best choice as a “rescue” regimen in our region.

High-dose versus low-dose clarithromycin in 1-week triple therapy, including rabeprazole and levofloxacin, for Helicobacter pylori eradication

GOALS

To compare high-dose versus low-dose clarithromycin in 1-week triple therapy including rabeprazole and levofloxacin.

BACKGROUND

Regimens containing rabeprazole and levofloxacin have proved to be effective against H. pylori infection.

STUDY

One-hundred H. pylori-positive patients were randomly assigned to one of the following 1-week regimens: rabeprazole 20 mg o.d. plus levofloxacin 500 mg o.d. and clarithromycin 250 mg b.d. (RLC-1 group); rabeprazole 20 mg o.d. plus levofloxacin 500 mg o.d. and clarithromycin 500 mg b.d. (RLC-2 group). H. pylori status was assessed at entry and after the treatment. Patients who experienced treatment failure underwent antibiotic susceptibility testing.

RESULTS

Forty-two patients in RLC-1 group (both PP and ITT analysis: 84%; 95%CI: 71-93%) and 47 in RLC2 group (both PP and ITT analysis: 94%; 95% CI: 83-98%) became H. pylori negative. Clarithromycin resistance was detected in all of 8 (100%) RLC-1 failures and in 1 out of 3 (33%) RLC-2 failures. Side effects occurred in 8% of patients in RLC-1 group and in 12% in RLC-2.

CONCLUSIONS

Regimens tested are competitive with other PPI-based treatments. One-week triple therapy containing rabeprazole plus, levofloxacin, and high-dose clarithromycin yielded a higher eradicating rate than the one containing low-dose clarithromycin and may be considered as a first-line therapy option.

Comparative efficacy of new investigational agents against Helicobacter pylori

BACKGROUND

Emergence of antibiotic resistant Helicobacter pylori has necessitated the identification of alternate therapies for the treatment of this infection.

AIM

To assess the in vitro efficacy of two investigational agents: DMG-MINO CL 344 (a N,N-dimethylglycylamido derivative of minocycline), and davercin, a cyclic carbonate of erythromycin A as compared to older antibiotics (clarithromcyin, azithromycin, minocycline, tetracycline, ofloxacin, ciprofloxacin, cefixime) against clinical isolates of H. pylori.

METHODS

Testing was performed using the agar dilution method approved by the NCCLS subcommittee on antimicrobial susceptibility testing, Helicobacter pylori working group. Under these guidelines, Mueller-Hinton agar containing 5% aged sheep blood was used. All incubations were done under CampyPak Plus conditions for 72 h at 37 degrees C. The drug concentrations in the agar ranged from 0.016 to 16 microg/mL. Twenty-one clarithromycin-resistant and 16 clarithromycin-susceptible clinical isolates of H. pylori obtained from patients with duodenal ulcer were used. H. pylori ATCC 43504 was used as the control in all determinations.

RESULTS

Against clarithromycin susceptible isolates, all antimicrobial agents except the fluoroquinolones were highly effective. Against clarithromycin-resistant H. pylori, the MIC50/MIC90 values showed that the tetracyclines and cefixime were the most efficacious agents. The fluoroquinolones and macrolides were ineffective. Macrolide cross-resistance was detected.

CONCLUSION

Macrolide cross-resistance prevents the use of this entire class of antimicrobials when clarithromycin resistance is present. Tetracyclines and cefixime are possible alternative agents for the treatment of H. pylori infection in these patients.

Efficacy of two one-week rabeprazole/levofloxacin-based triple therapies for Helicobacter pylori infection

BACKGROUND

One-week low-dose proton pump inhibitor-based triple therapies have usually proved to be effective treatments for Helicobacter pylori infection.

AIM

To investigate the eradication efficacy, safety profile and patient compliance of two triple therapies containing a standard dose of rabeprazole and a new fluoroquinolone, levofloxacin.

METHODS

One hundred patients referred to us for gastroscopy, who were H. pylori-positive, were consecutively recruited in a prospective, open-label study. The enrolled patients were randomised to receive a seven-day course of rabeprazole 20 mg o.d. plus levofloxacin 500 mg o.d. and either amoxycillin 1 g b.d. (RLA group) or tinidazole 500 mg b.d. (RLT group). Their H. pylori status was assessed by means of histology and rapid urease test at entry, and by 13C-urea breath test 8 weeks after the end of treatment.

RESULTS

All 100 enrolled patients completed the study. Forty-six of 50 patients treated with RLA (both PP and ITT analysis: 92%; 95% CI: 81-98%) and 45 of 50 with RLT (both PP and ITT analysis: 90%: 95% CI: 78-97%), became H. pylori-negative. Slight or mild side-effects occurred in 4 (8%) patients of the RLA group and in 5 (10%) of the RLT group.

CONCLUSIONS

This study demonstrates the efficacy of two 1-week rabeprazole-based triple therapies including levofloxacin to eradicate H. pylori. These regimens prove to be safe, well-tolerated, and achieved good eradication rates. Levofloxacin may be an effective alternative to clarithromycin in triple therapy regimens.

Effect of triple therapy on eradication of canine gastric helicobacters and gastric disease

Nine helicobacter-positive pet dogs with upper gastrointestinal signs were studied to evaluate the effect of a triple therapy, normally applied to humans for the eradication of gastric helicobacters, on clinical signs and gastric histology, as well as the recurrence of helicobacters after eradication in an extended follow-up in four dogs. Endoscopy was performed at entry to the study and repeated after eradication therapies and additional treatments. If the triple therapy (amoxycillin, metronidazole and bismuth subcitrate) failed, tetracycline and omeprazole were prescribed. Additional therapies were instituted if clinical signs persisted after eradication therapies. Helicobacter status was verified from gastric biopsy specimens by the urease test and histological examination, and in a few dogs also by brush cytology. Triple therapy eradicated gastric helicobacters in 7/9 dogs; gastric helicobacters were also eradicated in one dog treated with tetracycline and omeprazole. Eradication of helicobacters resulted in significant improvement, but not total resolution, of clinical signs. Subsequent additional therapies resulted in further alleviation of clinical signs. Neither triple therapy nor additional therapies had a significant effect on gastric histological changes. Gastric helicobacters recurred in 4/4 dogs within three years of the eradication treatment. Because canine gastric helicobacters alone were not definitively shown to induce clinical signs, routine eradication therapy seems not to be warranted at present.

A practical approach to patients with refractory Helicobacter pylori infection, or who are re-infected after standard therapy

The vast majority of recurrences of Helicobacter pylori infection after apparent eradication are observed during the first year. Almost all of these early recurrences are due to recrudescence rather than reinfection by a new strain. After the first year, the recurrence rates approximate to the rate of natural acquisition of H. pylori infection. By contrast, in developing countries, higher rates of recurrence suggest a major role of real reinfection. Important predictive factors of H. pylori treatment success are compliance and bacterial susceptibility to antibiotics. The new 1-week triple therapies, based on a proton pump inhibitor (PPI) and 2 antibiotics, lead to treatment discontinuation but rarely. If containing a nitroimidazole, their efficacy is reduced to 60 to 80% by pretreatment in vitro resistance. The prevalence of nitroimidazole resistance varies dependent on the geographical area, with rates over 50% in tropical regions. Resistance against macrolides hinders treatment success in 50 to 80% of patients. In the US, south-western Europe and Japan the prevalence of macrolide resistance amounts to about 10%, in other countries about 3%. After failed treatment, acquired resistance is frequent. Testing for resistance is recommended to facilitate the decision for an alternative triple therapy or for quadruple therapy comprising bismuth, metronidazole, tetracycline and a PPI. It seems reasonable to increase the dose of PPI in a retreatment regimen containing amoxicillin. Post-treatment double resistance against nitroimidazoles and macrolides reduces the success of most of the currently evaluated retreatment regimens. To overcome double resistance, high dose PPI plus amoxicillin is one approach, beside other experimental multidrug treatments.

Helicobacter Pylori

All infected patients with a peptic ulcer should be treated for H. pylori. The role of treating H. pylori in patients with undiagnosed dyspepsia or non-ulcer dyspepsia, those taking nonsteroidal anti-inflammatory medications, or with a family history of gastric cancer remains controversial. Triple therapies consisting of a proton pump inhibitor or ranitidine bismuth citrate and two antibiotics are the current standard of therapy for H. pylori. In general, dual therapies should no longer be used to treat H. pylori. Bismuth triple therapy consisting of bismuth, tetracycline, and metronidazole is a less expensive alternative to proton pump inhibitor-or ranitidine bismuth citrate-based triple therapies. However, bismuth triple therapy is hampered by frequent side effects and the need for qid dosing. In Europe, a 7-day course of therapy appears to be adequate. In the United States, 10-14 days of therapy are currently recommended. Metronidazole resistance in H. pylori strains varies geographically, and negatively influences the effectiveness of therapies containing this antibiotic. Clarithromycin resistance is relatively infrequent at the current time but may be rising in countries where this antibiotic is in use. If a patient remains infected after a course of therapy for H. pylori, the second treatment should avoid the antibiotics used initially.

Prospective evaluation of a new anti-ulcer agent, ecabet sodium, for the treatment of Helicobacter pylori infection

BACKGROUND

A new anti-ulcer agent, ecabet sodium, is active against Helicobacter pylori.

AIM

To assess the efficacy of ecabet sodium for the eradication of H. pylori in patients with gastroduodenal diseases.

METHODS

In a prospective, randomized and controlled study, patients infected with H. pylori were assigned to one of the following two groups: group LA, who received lansoprazole 30 mg o.d. + amoxycillin 500 mg q.d.s. after meals for 2 weeks, and group LAE, who received lansoprazole 30 mg o.d. + amoxycillin 500 mg q.d.s. + ecabet sodium 1000 mg b.d. after meals for 2 weeks. H. pylori status was determined before and at least 4 weeks after the therapy by rapid urease test, histology and a urea breath test.

RESULTS

Of 101 patients (mean age 53 years, range 17-77 years, M/F: 68/33) enrolled in the study, 97 patients completed the protocol. Four patients were withdrawn because of diarrhoea (three from group LA) and skin rash (one from group LAE). The eradication of H. pylori was achieved in 28/48 (58%) patients in group LA and 38/49 (78%) patients in group LAE. The rate of eradication of H. pylori produced by the LAE treatment was significantly higher than that produced by the LA treatment. Side-effects appeared in two patients (malaise 1, skin rash 1) in group LAE and in seven patients (diarrhoea 6, dizziness 1) in group LA. These side effects disappeared spontaneously with cessation of the treatment.

CONCLUSIONS

Ecabet sodium in combination with lansoprazole and amoxycillin increased the rate of eradication of H. pylori. Ecabet sodium appeared to reduce the incidence of diarrhoea as a side-effect of the dual LA therapy.

Eradication of Helicobacter pylori

Although there are numerous publications reporting eradication results, the general picture is confused by the bewildering multiplicity of treatment schedules employed by the various workers. The over-riding need now is for large scale trials, and more especially for direct comparisons of different treatment regimens in the same populations of patients. Such data are entirely absent from the literature at present. Standardization of definitions and of methodology pertaining to diagnosis of eradication, recording of side effects, measurement of compliance and determination of recurrence or of reinfection, is badly needed. As the definition of eradication remains arbitrary, it is important to include genome fingerprinting techniques in the long-term follow-up for recurrence, so that the question of reinfection versus recrudescence can be examined (Bell et al, 1993b; Xia et al, 1994). Because of the wide differences in the agents used in H. pylori eradication therapies, proper double-blinding of treatment trials remains a difficult problem. This can be dealt with to some extent by ensuring that the interpretation of tests for H. pylori eradication is performed by personnel unaware of the clinical details. Review of the existing data on eradication of H. pylori indicates that clinically useful results can be achieved in some 70 to 95% of patients, on an intention to treat basis. Compliance, side effects and resistance to metronidazole remain the limiting factors. Efficacy, freedom from side effects, simplicity and low cost will determine the success of any regimen in the future. At present, it is not possible to make firm recommendations in favour of one regimen over another, but it seems reasonable to forecast that dual therapies consisting of a PPI and an antibiotic will receive much attention. Preparations consisting of an H2RA associated with a bismuth compound, which are used together with an antibiotic are an interesting approach. Compliance should be as good as with a normal dual therapy and the eradication results look promising (Wyeth et al, 1994; Webb et al, 1994). The advantages of dual therapies that include a PPI lie in their simplicity, in not relying on imidazole for their anti-H. pylori effect but on the profound inhibition of acid output produced by the PPI. Thus PPI based dual therapy can probably evoke better compliance than the more complicated regimens. The use of PPIs has other advantages in addition to decreasing the MIC90 of the antibiotic combined with it. This is because administration of a powerful inhibitor of gastric acid secretion, such as a PPI, will aid the rapid healing of an ulcer crater and will rapidly relieve the symptoms of peptic ulceration. Gastrin releasing peptide-stimulated acid secretion is raised in duodenal ulcer patients to approximately sixfold over control levels according to El-Omar et al (1993b), and although it returns to normal following the eradication of H. pylori, this process takes time to become effective (El-Omar et al, 1993a). Suppression of acid output provides an immediate therapeutic shield, while the decrease in inflammation and acid output secondary to H. pylori eradication can be established. The most widespread resistance to antibiotics exhibited by H. pylori is with respect to imidazoles. The prevalence of metronidazole resistance is widespread in the emergent countries (Glupczynski et al, 1990), but it is also appreciable in the West, especially in women, who may have been given metronidazole in the treatment of pelvic infections (Rautelin et al, 1992; Banatvala et al, 1994). Moreover, H. pylori becomes resistant to metronidazole very easily and often as a result of treatment which includes an imidazole compound (Malfertheiner, 1993; Banatavala et al, 1994). On the other hand, H. pylori resistance to macrolides is not widespread and does not develop easily during their administration. It is difficult to forecast which antibiotic will be the most widely used agent

Treatment of Helicobacter pylori infection

Helicobacter pylori infects the human stomach and is associated with chronic gastritis, peptic ulcer disease and gastric cancer. Most patients with peptic ulcers are infected with H pylori. These patients suffer a high relapse rate following initial healing of the ulcer with anti-secretory agents. The rate of relapse can be greatly diminished following successful eradication of the organism. Although experience is still being accumulated, it is reasonable to use eradication therapy in any patient with H pylori positive active peptic ulcer disease. Combination triple and dual therapy regimens are effective but the search continues for better therapies. This review outlines the current evidence regarding which, when, how and with what H pylori infected patients should be treated.

Omeprazole. An update of its pharmacology and therapeutic use in acid-related disorders

Omeprazole, a gastric acid pump inhibitor, dose-dependently controls gastric acid secretion: the drug has greater antisecretory activity than histamine H2-receptor antagonists. Omeprazole 20 to 40 mg/day is more effective than histamine H2-receptor antagonists in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. Available data suggest that omeprazole 10 to 40 mg/day is also more effective than ranitidine in the maintenance therapy of duodenal ulcer and reflux oesophagitis. The drug is also effective in patients with duodenal ulcer, gastric ulcer or reflux oesophagitis poorly responsive to histamine H2-receptor antagonists. The efficacy of omeprazole 20 mg/day appears to be similar to that of lansoprazole 30 mg/day in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. However, most available studies have been reported in abstract form only, and 2 of 3 studies in patients with duodenal ulcer have shown greater healing rates at 2 (but not 4) weeks with lansoprazole. Helicobacter pylori eradication decreases duodenal ulcer relapse rates and appears to be associated with improved duodenal ulcer healing rates. Evidence also suggests that H. pylori eradication is associated with reduced gastric ulcer relapse rates. Omeprazole monotherapy may suppress but does not eradicate H. pylori infection. Eradication rates with omeprazole 20 or 40 mg twice daily plus amoxicillin usually up to 2 g/day (3 g/day in a few studies) for 2 weeks appear to be similar to those of standard triple therapy (bismuth salt plus metronidazole, plus tetracycline or amoxicillin) or omeprazole plus clarithromycin, although eradication rates vary widely. Omeprazole plus amoxicillin appears to be better tolerated than triple therapy and represents a first-line treatment alternative in patients with H. pylori-associated peptic ulcer disease. Omeprazole plus amoxicillin plus metronidazole appears to be more effective than omeprazole plus amoxicillin in patients with metronidazole-sensitive H. pylori infection. Omeprazole remains a treatment of choice in patients with Zollinger-Ellison syndrome. The dosages should be adjusted according to individual response. However, relatively low dosages of 10 to 40 mg/day may be sufficient in some patients. The drug has also shown promise in the treatment of children with severe reflux oesophagitis, in patients with reflux oesophagitis and coexisting systemic sclerosis, and in the prevention of aspiration pneumonia. Evidence suggests that omeprazole is more effective than ranitidine in patients with nonsteroidal anti-inflammatory drug (NSAID)-induced gastric damage who continue to take NSAIDs, especially in patients with large gastric ulcers; however, completion of ongoing studies is required to verify this.(ABSTRACT TRUNCATED AT 400 WORDS)

Treatment of peptic ulcers from now to the millennium

The present strategies for the management of peptic ulceration are well tolerated and clinically effective. Histamine H2-receptor antagonists can be used for mild to moderate disease, and proton pump inhibitors are of particular benefit for patients with severe peptic ulceration and the Zollinger-Ellison syndrome. However, none of these treatments provides protection against recurrent ulceration, except when taken as long-term continuous treatment. Long-term exposure to pharmacological agents raises problems of safety, particularly relating to a lack of intragastric acidity. In addition, the accelerated development of atrophic gastritis in patients receiving omeprazole requires investigation and assessment. It is unlikely that there will be any major development in the area of control of gastric acid secretion, except perhaps the introduction of specific immunization against gastrin. However, the clinical benefit of this strategy awaits assessment. The main area for development must be the introduction of convenient and effective regimens for the eradication of Helicobacter pylori infection. Existing regimens are either simpler and relatively ineffective, or too complicated for widespread application. Bearing in mind the long gestation period of any new drug, it seems likely that the only innovative drug that will be introduced for the management of peptic ulceration before the millennium will be ranitidine bismuth citrate, an antisecretory anti-H. pylori drug that will usually be used in combination with an antibiotic.

Duodenal ulcer treatment: progress from pH to HP

The treatment of duodenal ulcer has evolved from ineffective medical treatments through an era of surgical management, back to increasingly effective medical treatment. The advent of H2-receptor antagonists changed the outlook for ulcer patients. More recently, Helicobacter pylori, an organism which inhabits gastric mucosa exclusively, has been implicated in the pathogenesis of peptic ulcer. This bacterium is found in the stomachs of around 95% of duodenal ulcer patients. Its eradication is shown dramatically to improve the rate at which ulcers relapse. The mechanisms whereby it may cause ulceration are not established--we review current hypotheses. No method of eradication is 100% effective, and many different dual or triple therapy regimens have been tried. Metronidazole resistance is reported but its importance is not yet known. Helicobacter eradication is likely to prove a cost-effective and acceptable treatment for duodenal ulcer, and once its value has gained acceptance widespread uptake of this option is anticipated.

Evaluation of a new immunodiagnostic assay for Helicobacter pylori antibody detection: correlation with histopathological and microbiological results

Infection with Helicobacter pylori has been associated with the pathogenesis of chronic active gastritis and gastric and duodenal ulcer disease. Detection of immunoglobulin G antibodies to H. pylori offers a simple alternative to direct detection of the organism in biopsied tissue by culture or histopathological methods. A rapid flow-through membrane-based enzyme immunoassay for the detection of human immunoglobulin G antibodies to H. pylori has been developed and evaluated. Clinical evaluations were performed with 256 patient serum samples obtained from four clinical sites. Biopsy samples were obtained by endoscopic procedures at the same time as the serum samples, and were histopathologically and microbiologically categorized for the presence or absence of H. pylori. Sensitivity and specificity for this rapid enzyme immunoassay were 92 and 88%, respectively, compared directly with endoscopy results. After discordant results were resolved by a quantitative microwell enzyme-linked immunosorbent assay, the resulting sensitivity and specificity were 94 and > 99%, respectively. These results indicate that this rapid enzyme immunoassay is a useful technique to determine H. pylori infection status and is a viable alternative to invasive endoscopic procedures.