Evolving therapy for Helicobacter pylori infection

Role of gastritis pattern on Helicobacter pylori eradication

Helicobacter pylori eradication rate following standard triple therapy is decreasing. Identification of predictive factors of therapy success would be useful for H. pylori management in clinical practice. This study aimed to evaluate the role of different gastritis patterns on the efficacy of the currently suggested 14-day triple therapy regimen. One-hundred and seventeen, consecutive, non-ulcer dyspeptic patients, with H. pylori infection diagnosed at endoscopy, were enrolled. All patients received a 14-day, triple therapy with lansoprazole 30 mg, clarithromycin 500 mg and amoxicillin 1 g, all given twice daily. Bacterial eradication was assessed with (13)C-urea breath test 4-6 weeks after completion of therapy. H. pylori infection was cured in 70.1% at ITT analysis and 83.7% at PP analysis. The eradication rate tended to be lower in patients with corpus-predominant gastritis as compared to those with antral-predominant gastritis at both ITT (66.1 vs 74.5%) and PP (80.4 vs 87.2%) analyses. The multivariate analysis failed to identify factors associated with therapy success. However, 14-day triple therapy does not achieve acceptable H. pylori cure rate in Italy, and should be not recommended in clinical practice.

Different Antibiotic No Culture Eradicating (DANCE) strategy: an easy way to manage H. pylori eradication

Treatment of Helicobacter pylori infection is becoming a very relevant problem especially in industrialized Countries. Although different therapeutic regimens are currently available, treatment failure remains a growing problem in daily medical practice. Several factors could play a role in the eradication failure, but the most relevant are antibiotic resistance and patient's compliance. While Helicobacter pylori resistance to amoxicillin is rare, clarithromycin and metronidazole resistance varies significantly from close to zero up to 25%. However, metronidazole in vitro resistance exhibits a lower impact on eradication success because resistance in vitro does not reflect that in vivo. Specific guidelines have then been published, mostly based on antibiotic resistance among different geographic areas. Basically, first-line and second-line regimens have been well defined; concerning third-line treatment Maastricht III guidelines suggest to adopt a culture-based approach. Culture is, however, expensive, invasive and available only in few specialized centres. An alternative approach may be to use an empirical strategy, based on the avoidance of repeating similar eradicating schemes in the same patients during the course of different eradicating regimens. For this approach we propose the acronym DANCE (Different Antibiotic No Culture Eradicating) strategy. When correctly applied, this approach showed to reach successful eradication in up to 99.5% of Helicobacter pylori-positive patients.

"Cervia II Working Group Report 2006": guidelines on diagnosis and treatment of Helicobacter pylori infection in Italy

Proper management of Helicobacter pylori infection in clinical practice--when supported by evidence-based data--is expected to produce substantial cost-efficacy advantages. This consideration has prompted the Cervia Working Group to organise a meeting of experts to update the National Guidelines on the diagnosis and treatment of H. pylori infection in Italy. Recommendations in the new European Guidelines were considered in the National setting, here in the light of factors such as the incidence of gastric cancer and gastric lymphoma, the accessibility to different diagnostic tools, the prevalence of bacterial resistance against antibiotics, and the availability of different drugs. The main revisions in respect to the previous guidelines include H. pylori eradication in non-ulcer dyspepsia patients and in non-steroidal, anti-inflammatory drug users, as well as in patients with idiopathic thrombocytopenic purpura and iron deficiency anaemia. The stool antigen test is now accepted as a valid test for confirmation of H. pylori eradication following therapy. New therapeutic approaches have been recommended for both first- (sequential therapy) and second-line (levofloxacin-based) treatment in our country.

Rapid detection of clarithromycin-resistant Helicobacter pylori in patients with dyspepsia by fluorescent in situ hybridization (FISH) compared with the E-test

BACKGROUND

Clarithromycin is the antibiotic of choice for treatment of H.pylori-related dyspepsia, but unfortunately, resistance to clarithromycin is not rare. Detection of resistant strains takes 2 to 4 days by conventional methods. In this report, we applied the FISH technique for rapid detection of H.pylori in biopsies of dyspeptic patients.

METHODS

Gastric biopsies from 50 patients suffering from dyspepsia were tested in this study. Part of each biopsy specimen was cultured and the remainder was fixed in liquid nitrogen. After mounting of frozen sections on microscopic slides, they were hybridized with oligonucleotide probes for detection of clarithromycin-resistant H.pylori. The slides were visualized under a fluorescent microscope. Susceptibility of cultured strains of H. pylori to clarithromycin was also determined by the E-test and the results were compared.

RESULTS

Twenty-five of 50 biopsy specimens examined by FISH were positive for H.pylori. FISH showed that 17 strains (68%) were susceptible to clarithromycin and 6 strains (24%) were resistant. Bacteria isolated following culture of 2 biopsy specimens had a mixture of both clarithromycin-susceptible and resistant strains (8%). There was no discrepancy between the E-test and FISH technique for detection of resistant strains of H.pylori.

CONCLUSION

FISH is a rapid technique for detection of H.pylori in clinical samples. Moreover, strains susceptible to clarithromycin can be detected quickly. Therefore, this method is suitable for determination of susceptibility of H.pylori to clarithromycin, especially when a quick decision is necessary for treating dyspeptic patients.

Rifaximin, a poorly absorbed antibiotic: pharmacology and clinical potential

Rifaximin (4-deoxy-4'-methylpyrido[1',2'-1,2]imidazo- [5,4-c]-rifamycin SV) is a synthetic antibiotic designed to modify the parent compound, rifamycin, in order to achieve low gastrointestinal (GI) absorption while retaining good antibacterial activity. Both experimental and clinical pharmacology clearly show that this compound is a nonsystemic antibiotic with a broad spectrum of antibacterial action covering Gram-positive and Gram-negative organisms, both aerobes and anaerobes. Being virtually nonabsorbed, its bioavailability within the GI tract is rather high with intraluminal and fecal drug concentrations that largely exceed the minimal inhibitory concentration values observed in vitro against a wide range of pathogenic organisms. The GI tract represents, therefore, the primary therapeutic target and GI infections the main indication. The appreciation of the pathogenic role of gut bacteria in several organic and functional GI diseases has increasingly broadened its clinical use, which is now extended to hepatic encephalopathy, small intestine bacterial overgrowth, inflammatory bowel disease and colonic diverticular disease. Potential indications include the irritable bowel syndrome and chronic constipation, Clostridium difficile infection and bowel preparation before colorectal surgery. Because of its antibacterial activity against the microorganism and the lack of strains with primary resistance, some preliminary studies have explored the rifaximin potential for Helicobacter pylori eradication. Oral administration of this drug, by getting rid of enteric bacteria, could also be employed to achieve selective bowel decontamination in acute pancreatitis, liver cirrhosis (thus preventing spontaneous bacterial peritonitis) and nonsteroidal anti-inflammatory drug (NSAID) use (lessening in that way NSAID enteropathy). This antibiotic has, therefore, little value outside the enteric area and this will minimize both antimicrobial resistance and systemic adverse events. Indeed, the drug proved to be safe in all patient populations, including young children. Although rifaximin has stood the test of time, it still attracts the attention of both basic scientists and clinicians. As a matter of fact, with the advancement of the knowledge on microbial-gut interactions in health and disease novel indications and new drug regimens are being explored. Besides widening the clinical use, the research on rifaximin is also focused on the synthesis of new derivatives and on the development of original formulations designed to expand the spectrum of its clinical use.

Quadruple therapy with lactoferrin for Helicobacter pylori eradication: a randomised, multicentre study

BACKGROUND

Helicobacter pylori eradication rate with standard triple therapies is decreasing. Recently, lactoferrin administration has been shown to significantly increase the cure rate of 7-day rabeprazole, clarithromycin and tinidazole triple therapy. We assessed whether lactoferrin also increases the eradication rate of 7-day esomeprazole, clarithromycin and amoxycillin triple therapy as first-line treatment.

METHODS

Overall, 133 consecutive patients with non-ulcer dyspepsia and H. pylori infection were randomised to receive either a standard 7-day triple therapy with esomeprazole 20mg b.i.d., clarithromycin 500 mg b.i.d. and amoxycillin 1g b.i.d. (68 patients) or a quadruple therapy comprising of the same regimen plus lactoferrin 200mg b.i.d. (65 patients). H. pylori at entry was assessed by endoscopy, while bacterial eradication was checked by (13)C urea breath test 4-6 weeks after treatment.

RESULTS

H. pylori eradication following standard triple therapy was achieved in 53/68 (77.9%; 95% CI = 68-88) and in 53/66 (80.3%; 95% CI = 71-89) patients at ITT and PP analyses, respectively. Following the quadruple regimen, the infection was cured in 50/65 (76.9%; 95% CI = 67-87) and 50/64 (78.1%; 95% CI = 68-88) patients at ITT and PP analyses, respectively. No statistically significant difference emerged between the two therapeutic regimens, both at ITT (p = 0.9) and PP analyses (p = 0.9). Side effects were complained by seven (10.3%) patients and six (9.2%) patients following the triple and quadruple regimens, respectively (p = 0.9), with only one patient in the quadruple group interrupting the treatment due to side effects.

CONCLUSIONS

Quadruple therapy with lactoferrin did not significantly increase the H. pylori cure rate of standard 7-day clarithromycin-amoxycillin based triple therapy in non-ulcer dyspepsia patients.