Treatment of Helicobacter pylori

Anti-Heliobacter pylori and Anti-Inflammatory Potential of Salvia officinalis Metabolites: In Vitro and In Silico Studies

Due to its rising antibiotic resistance and associated inflammations, Helicobacter pylori poses a challenge in modern medicine. Salvia officinalis, a member of the Lamiaceae family, is a promising medicinal herb. In this regard, a phytochemical screening followed by GC-MS and LC-MS was done to evaluate the chemical profile of the total ethanolic extract (TES) and the essential oil, respectively. The anti-H. pylori and the anti-inflammatory activities were evaluated by a micro-well dilution technique and COX-2 inhibition assay. Potential anti-H. pylori inhibitors were determined by an in silico study. The results revealed that the main metabolites were flavonoids, sterols, volatile oil, saponins, and carbohydrates. The LC-MS negative ionization mode demonstrated 12 compounds, while GC-MS showed 21 compounds. Carnosic acid (37.66%), epirosmanol (20.65%), carnosol1 (3.3%), and 12-O-methyl carnosol (6.15%) were predominated, while eucalyptol (50.04%) and camphor (17.75%) were dominant in LC-MS and GC-MS, respectively. TES exhibited the strongest anti-H. pylori activity (3.9 µg/mL) asymptotic to clarithromycin (0.43 µg/mL), followed by the oil (15.63 µg/mL). Carnosic acid has the best-fitting energy to inhibit H. pylori (-46.6769 Kcal/mol). TES showed the highest reduction in Cox-2 expression approaching celecoxib with IC50 = 1.7 ± 0.27 µg/mL, followed by the oil with IC50 = 5.3 ± 0.62 µg/mL. Our findings suggest that S. officinalis metabolites with anti-inflammatory capabilities could be useful in H. pylori management. Further in vivo studies are required to evaluate and assess its promising activity.

Comparison of efficacy and pharmacoeconomics of two Helicobacter pylori eradication regimens in peptic ulcer disease

Background

Helicobacter pylori, the cause of most peptic ulcer diseases, infects approximately 50% of the population worldwide. Indian data on cost and effectiveness of the standard first-line therapies for H. pylori eradication are scarce. Thus, the present study was aimed at comparing the cost and efficacy of two standard first-line therapies: Regimen I comprising pantoprazole (40 mg) plus amoxicillin (750 mg) plus clarithromycin (500 mg) (PAC) and Regimen II comprising rabeprazole (20 mg) plus amoxicillin (625 mg) plus metronidazole (200 mg) (RAM).

Methodology

This prospective, observational, bottom-up study collected demographic, economic, diagnostic, and therapeutic data from 60 H. pylori-positive patients. The study was carried out for 6 months in the Gastroenterology Department of a Tertiary Care Hospital in Hyderabad, Telangana, India.

Results

Health-care system perspective was used to account for direct costs. Average cost per patient for complete H. pylori eradication was Rs. 10,221 and Rs. 8568 for Regimen I and Regimen II, respectively. Inpatient cost was considerably higher than the outpatient cost. Diagnostic costs ranked first in direct costs, followed by hospitalization costs, medication costs, and finally, physician's office visit cost. Individual patient's costs difference between two regimens was found to be statistically significant. Overall, Regimen I proved to be more efficacious than Regimen II, but Regimen II proved to be more cost-effective than Regimen I. Furthermore, incremental cost-effectiveness analysis revealed additional cost of Rs. 127 per patient if the patient was treated with Regimen I instead of Regimen II.

Conclusion

Our study showed that Regimen II (RAM) was more cost-effective than Regimen I (PAC), but PAC achieved faster H. pylori eradication than RAM. We assume that this study provides local clinical data as to which regimen may be useful in a particular patient. National Level Clinical Trials are required to further ascertain this conclusion.

Development of Floating-Mucoadhesive Microsphere for Site Specific Release of Metronidazole

PURPOSE

The purpose of this study was to develop and evaluate metronidazole loaded floating-mucoadhesive microsphere for sustained drug release at the gastric mucosa.

METHODS

Alginate gastroretentive microspheres containing metronidazole were prepared by ionic gelation method using sodium bicarbonate as gas forming agent, guar gum as mucoadhesive polymer, and Eudragit L100 as drug release modifier. Carbopol was used for increasing the bead strength. The microspheres were characterized by scanning electron microscopy and evaluated by means of drug entrapment efficiency, in vitro buoyancy, and swelling studies. In vitro mucoadhesion and drug release studies were carried out in order to evaluate site specific sustained drug release.

RESULTS

All formulations showed 100% buoyancy in vitro for a prolonged period of time. Amount of guar gum influenced the properties of different formulations. The formulation containing drug and guar gum at a ratio of 1:0.5 showed the best results with 76.3% drug entrapment efficiency, 61.21% mucoadhesion, and sustained drug release. Carbopol was found to increase surface smoothness of the microspheres.

CONCLUSION

Metronidazole mucoadhesive-floating microspheres can be effectively used for sustained drug release to the gastric mucosa in treatment of upper GIT infection.

Medicinal plants in the treatment of Helicobacter pylori infections

CONTEXT

Helicobacter pylori is a small, spiral, Gram-negative bacillus that plays a role in the pathogenesis of a number of diseases ranging from asymptomatic gastritis to gastric cancer. Schedule compliance, antibiotic drug resistance, and side-effects of triple or quadruple therapy have led to research for novel candidates from plants.

OBJECTIVE

The purpose of this paper is to review the most potent medicinal plants of recently published literature with anti-H. pylori activity. For centuries, herbals have been used by traditional healers around the world to treat various gastrointestinal tract disorders such as dyspepsia, gastritis, and peptic ulcer disease. The mechanism of action by which these botanicals exert their therapeutic properties has not been completely and clearly elucidated. Anti-H. pylori properties may be one of the possible mechanisms by which gastroprotective herbs treat gastrointestinal tract disorders.

MATERIALS AND METHODS

Electronic databases such as PubMed, Google scholar, EBSCO, and local databases were explored for medicinal plants with anti-H. pylori properties between 1984 and 2013 using key words "medicinal plants" and "Helicobacter pylori" or "anti-Helicobacter pylori".

RESULTS

A total of 43 medicinal plant species belonging to 27 families including Amaryllidaceae, Anacardiaceae, Apiaceae, Apocynaceae, Asclepiadoideae, Asteraceae, Bignoniaceae, Clusiaceae, Chancapiedra, Combretaceae, Cyperaceae, Euphorbiaceae, Fabaceae, Geraniaceae, Lamiaceae, Lauraceae, Lythraceae, Menispermaceae, Myristicaceae, Myrtaceae, Oleaceae, Papaveraceae, Plumbaginaceae, Poaceae, Ranunculaceae, Rosaceae, and Theaceae were studied as herbs with potent anti-H. pylori effects.

CONCLUSION

Traditional folk medicinal use of some of these plants to treat gastric infections is substantiated by the antibacterial activity of their extracts against H. pylori.

The Helicobacter pylori resistance rate to clarithromycin in Iran

BACKGROUND

Clarithromycin is the most commonly suggested antibiotic in Helicobacter pylori eradication regimens. Increasing antibiotic resistance rate to clarithromycin is the main reason for therapeutic failure. The resistance is associated with mutations in the 23S rRNA gene.

AIM

The purpose of this study was to determine the clarithromycin resistance rate of isolated H. pylori strains from referral patients in Kashan, Iran.

METHODS

In total 95 H. pylori strains isolated from gastric mucosa of 246 patients with different clinical signs underwent gastroscopy in Kashan, Iran in 2013. The Epsilometer test was used to determine the minimum inhibitory concentrations (MICs) of clarithromycin (CLR) in isolated H. pylori strains. Occurrence of mutation in 23S rRNA gene of clarithromycin-resistant strains was investigated with polymerase chain reaction-sequencing method.

RESULTS

Antibiotic susceptibility pattern showed that 32 strains (33.7%) were resistant to clarithromycin (MICs ≥1 μg/ml), 33.7% were intermediate resistant, while 31 of H. pylori strains (32.6%) were susceptible. The 23S rRNA gene mutations at positions A2143G and A2142G were detected in H. pylori clarithromycin-resistant strains.

CONCLUSION

The resistance rate to clarithromycin in Iran is high. H. pylori clarithromycin-resistant strains were not associated with sex, age, and disease. The A2143G mutation in clarithromycin-resistant H. pylori strains was the predominant finding.

Antibiotics resistance of Helicobacter pylori and treatment modalities in children with H. pylori infection

Pediatric infection with Helicobacter pylori may occur early in childhood and persist lifelong. Global pediatric clinical studies have reported a decreasing tendency in the overall rate of H. pylori eradication. In pediatric patients with H. pylori infection, pediatric patients with peptic ulcer, and the first-degree relatives of patients with a history of gastric cancer, it is commonly recommended that H. pylori strains be eradicated. Antibiotic drug resistance to H. pylori, which has been reported to vary widely between geographic regions, is mainly associated with treatment failure in these patients. It is therefore imperative that the antibiotic resistance rates of H. pylori in children and adolescents be meticulously monitored across countries and throughout geographic regions. This paper particularly focuses on the antibiotic drug resistance of H. pylori and the thearpy of pediatric H. pylori infection cases.

High Helicobacter pylori resistance to metronidazole and clarithromycin in Brazilian children and adolescents

OBJECTIVE

The aim of the present study was to assess the primary and secondary resistance of Helicobacter pylori strains to clarithromycin, amoxicillin, furazolidone, tetracycline, and metronidazole, the conventional antibiotics presently used in Brazilian children and adolescents.

METHODS

Seventy-seven consecutive H pylori strains, 71 of 77 strains obtained from patients without previous eradication treatment for H pylori infection, and 6 strains from patients in whom previous eradication treatment had failed.

RESULTS

Global rate of resistance was 49.3% (38/77): 40% of strains were resistant to metronidazole, 19.5% to clarithromycin, and 10.4% to amoxicillin. All of the tested H pylori strains were susceptible to furazolidone and tetracycline. Multiple resistance were detected in 18.2% (14/77 patients) of the strains: 6 of 14 (43%) simultaneously resistant to clarithromycin and metronidazole; 5 of 14 (36%) to amoxicillin and metronidazole; 2 of 14 (14%) to amoxicillin, clarithromycin, and metronidazole; and 1 of 14 (7%) to clarithromycin and amoxicillin.

CONCLUSIONS

The high resistance rate to metronidazole and clarithromycin observed in clinical H pylori isolates can exclude these antimicrobials in empirical eradication treatment in Brazil. Otherwise, furazolidone and tetracycline presented no resistance. Properly assessing the risks and benefits, these 2 antimicrobials and their derivatives could be used in empirical eradication schedules, both associated with amoxicillin, which showed a low resistance rate despite its wide use in pediatric patients.

A role for altered phagosome maturation in the long-term persistence of Helicobacter pylori infection

The vigorous host immune response that is mounted against Helicobacter pylori is unable to eliminate this pathogenic bacterium from its niche in the human gastric mucosa. This results in chronic inflammation, which can develop into gastric or duodenal ulcers in 10% of infected individuals and gastric cancer in 1% of infections. The determinants for these more severe pathologies include host (e.g., high IL-1β expression polymorphisms), bacterial [e.g., cytotoxicity-associated gene (cag) pathogenicity island], and environmental (e.g., dietary nitrites) factors. However, it is the failure of host immune effector cells to eliminate H. pylori that underlies its persistence and the subsequent H. pylori-associated disease. Here we discuss the mechanisms used by H. pylori to survive the host immune response and, in particular, the role played by altered phagosome maturation.

Alternative therapies for Helicobacter pylori: probiotics and phytomedicine

Helicobacter pylori is a common human pathogen infecting about 30% of children and 60% of adults worldwide and is responsible for diseases such as gastritis, peptic ulcer and gastric cancer. Treatment against H. pylori is based on the use of antibiotics, but therapy failure can be higher than 20% and is essentially due to an increase in the prevalence of antibiotic-resistant bacteria, which has led to the search for alternative therapies. In this review, we discuss alternative therapies for H. pylori, mainly phytotherapy and probiotics. Probiotics are live organisms or produced substances that are orally administrated, usually in addition to conventional antibiotic therapy. They may modulate the human microbiota and promote health, prevent antibiotic side effects, stimulate the immune response and directly compete with pathogenic bacteria. Phytomedicine consists of the use of plant extracts as medicines or health-promoting agents, but in most cases the molecular mode of action of the active ingredients of these herbal extracts is unknown. Possible mechanisms include inhibition of H. pylori urease enzyme, disruption of bacterial cell membrane, and modulation of the host immune system. Other alternative therapies are also reviewed.

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.

Curcumin alleviates matrix metalloproteinase-3 and -9 activities during eradication of Helicobacter pylori infection in cultured cells and mice

Current therapy-regimens against Helicobacter pylori (Hp) infections have considerable failure rates and adverse side effects that urge the quest for an effective alternative therapy. We have shown that curcumin is capable of eradicating Hp-infection in mice. Here we examine the mechanism by which curcumin protects Hp infection in cultured cells and mice. Since, MMP-3 and -9 are inflammatory molecules associated to the pathogenesis of Hp-infection, we investigated the role of curcumin on inflammatory MMPs as well as proinflammatory molecules. Curcumin dose dependently suppressed MMP-3 and -9 expression in Hp infected human gastric epithelial (AGS) cells. Consistently, Hp-eradication by curcumin-therapy involved significant downregulation of MMP-3 and -9 activities and expression in both cytotoxic associated gene (cag)(+ve) and cag(-ve) Hp-infected mouse gastric tissues. Moreover, we demonstrate that the conventional triple therapy (TT) alleviated MMP-3 and -9 activities less efficiently than curcumin and curcumin's action on MMPs was linked to decreased pro-inflammatory molecules and activator protein-1 activation in Hp-infected gastric tissues. Although both curcumin and TT were associated with MMP-3 and -9 downregulation during Hp-eradication, but unlike TT, curcumin enhanced peroxisome proliferator-activated receptor-γ and inhibitor of kappa B-α. These data indicate that curcumin-mediated healing of Hp-infection involves regulation of MMP-3 and -9 activities.

Selected South African honeys and their extracts possess in vitro anti-Helicobacter pylori activity

BACKGROUND AND AIMS

Eradication of Helicobacter pylori by triple therapy often results in a failure rate of 10-20%; thus, there is a need to seek alternative treatments. The aim of this study was to screen selected South African honeys for their anti-H. pylori activity, to extract the antimicrobial components using organic solvents and to determine the minimum inhibitory concentrations (MICs) of the extracts.

METHODS

Three locally produced honeys from different regions in South Africa were screened for anti-H. pylori activity at four different concentrations using the agar well diffusion technique. Subsequently, Pure honey was extracted using n-hexane, diethyl ether, chloroform and ethyl acetate; extracts were also examined for anti-H. pylori activity by agar well diffusion method. The MICs of the three most active extracts were determined both by visual inspection and spectrophotometric analysis at 620 nm using the broth microdilution method. The results were analyzed by one-way ANOVA at 95% significance level.

RESULTS

All honeys demonstrated anti-H. pylori activity and were most active at 75% v/v. The positive control (clarithromycin) recorded a zone diameter of 18.0 ± 7.4 mm not significantly different (p >0.05) from honeys at 75% v/v and solvent extracts. Chloroform extract recorded the lowest MIC(95) values that ranged from 0.156-5% v/v confirming this extract to be the most active.

CONCLUSION

All honeys demonstrated anti-H. pylori activity at concentrations ≥10%, as did the solvent extracts. Therefore, these honeys and solvent extracts possess potential compounds with therapeutic activity that could be further exploited as lead molecules in the treatment of H. pylori infections.

5-Nitroimidazole-based 1,3,4-thiadiazoles: heterocyclic analogs of metronidazole as anti-Helicobacter pylori agents

A series of 5-nitroimidazole-based 1,3,4-thiadiazoles were prepared and tested for antibacterial activity against Helicobacter pylori. The anti-H. pylori activity of target compounds along with the commercially available antimicrobial metronidazole was evaluated by comparing the inhibition-zone diameters determined by the paper disc diffusion bioassay. From our bioassay results against 20 clinical isolates it is evident that piperazinyl, 4-methylpiperazinyl, 3-methylpiperazinyl, and 3,5-dimethylpiperazinyl analogs (6a, 6b, 6e, and 6f, respectively) and pyrrolidine derivative 7 had strong activity at 0.5 µg/disc (average of inhibition zone > 20 mm) while metronidazole had no activity at this dose. Compound 6f containing the 3,5-dimethylpiperazinyl moiety at the 2-position of the 5-(1-methyl-5-nitro-1H-imidazol-2-yl)-1,3,4-thiadiazole skeleton was the most potent compound tested at low concentrations.

Ureases as a target for the treatment of gastric and urinary infections

Urease is known to be a major contributor to pathologies induced by Helicobacter pylori and Proteus species. In H pylori, urease allows the bacteria to survive in an acidic gastric environment during colonisation, playing an important role in the pathogenesis of gastric and peptic ulcers. Ureolytic activity also results in the production of ammonia in close proximity to the gastric epithelium, causing cell damage and inflammation. In the case of Proteus species (notably Proteus mirabilis) infection, stones are formed due to the presence of ammonia and carbon dioxide released by urease action. In addition, the ammonia released is able to damage the glycosaminoglycan layer, which protects the urothelial surface against bacterial infection. In this context, the administration of urease inhibitors may be an effective therapy for urease-dependent pathogenic bacteria. This is a review of the role of ureases in H pylori and Proteus species infections, focussing on the biochemical and clinical aspects of the most promising and/or potent urease inhibitors for the treatment of gastric and urinary tract infections.

Rabeprazole can overcome the impact of CYP2C19 polymorphism on quadruple therapy

OBJECTIVES

The prospective study was designed to clarify the impact of CYP2C19 on quadruple therapies and survey the efficacies of rabeprazole-based quadruple therapy for Helicobacter pylori infection after failure of standard triple therapies.

PATIENTS AND METHODS

From January 2007 to March 2009, 1055 H. pylori-infected patients received standard triple regimens (proton-pump inhibitor (PPI), clarithromycin, and amoxicillin). Helicobacter pylori eradication was achieved in 865 (81.9%) subjects. One hundred ninety eradication-failure patients were enrolled and randomly assigned to receive a 7-day eradication therapy. Ninety-six patients were treated with esomeprazole-based quadruple rescue therapies (EB), while 94 patients were treated with rabeprazole-based quadruple rescue therapies (RB). Follow-up endoscopy was done 16 weeks later to assess the treatment response. Patients' responses, CYP2C19 genotypes, and antibiotics resistances were also examined.

RESULTS

Intention-to-treat analysis revealed that RB had better eradication rates than EB (EB: 72.9%; 95% CI: 64.9-80.9% and RB: 78.7%; 95% CI 72.5-84.9%) (p value = .543). Per-protocol results were EB = 75.3%; 95% CI: 70.3-80.3% and RB = 85.1%; 95% CI: 80.6-89.6% (p value = .0401). Both regimens had similar compliance (p value = 0.155) and adverse events (p value = 0.219). We also surveyed those patients without resistance of any antibiotics. RB still showed better outcome than EB. Our data showed that esomeprazole-based regimen and CYP2C19 Hom EM genotype were important predictors for eradication failure.

CONCLUSIONS

In quadruple therapy, rabeprazole-based regimens had better efficacy than esomeprazole-based regimens. CYP2C19 polymorphism also played an important role in quadruple therapy. It seems advisable to change PPI to rabeprazole in second-line quadruple therapy.

An African perspective on Helicobacter pylori: prevalence of human infection, drug resistance, and alternative approaches to treatment

Helicobacter pylori is a Gram-negative, micro-aerophilic, motile, curved rod that inhabits the gastric mucosa of the human stomach. It chronically infects thousands of millions of people world-wide, and is one of the most genetically diverse of bacterial species. Infection with the bacterium leads to chronic gastritis, peptic ulceration, gastric cancers and gastric mucosa-associated lymphoid-tissue (MALT) lymphoma. The prevalence of infection appears to be partly determined by geographical and socio-demographic factors, being higher in Africa than elsewhere. Current treatment, based on potent combinations that each consist of a proton-pump inhibitor and two antibiotics, is successful in 80%-90% of patients. Some undesirable side-effects, poor patient compliance and drug resistance are, however, associated with significant levels of treatment failure and with contra-indications for some patients. Antibiotic resistance in H. pylori is a growing global concern that merits the urgent attention of public-health authorities. Numerous pieces of clinical evidence have revealed that eradication of the organism from a patient results in improvement of gastritis and drastically decreases the frequency of relapse of gastric and duodenal ulcers. Natural products, including medicinal plants and honey, may offer useful alternatives in the treatment of H. pylori-related infections.

Sequential and concomitant therapy with four drugs is equally effective for eradication of H pylori infection

BACKGROUND & AIMS

Sequential therapy with a proton pump inhibitor (PPI) and amoxicillin followed by a PPI, clarithromycin, and an imidazole agent reportedly have a better rate of curing Helicobacter pylori infection than PPI, amoxicillin, and clarithromycin triple therapy. The concomitant administration of these 4 drugs (concomitant therapy) is also an effective treatment strategy. We compared the efficacies of sequential and concomitant therapy and analyzed the effects of antibiotic resistance in patients with H pylori infection.

METHODS

In a randomized trial of 232 H pylori-infected patients from 3 hospitals in Kaohsiung, Taiwan, patients were given 10 days of sequential (n = 115) or concomitant (n = 117) therapy. H pylori status was confirmed by endoscopy or urea breath test.

RESULTS

Intention-to-treat analysis demonstrated similar eradication rates for sequential (92.3%; 95% confidence interval [CI], 87.5%-97.1%) and concomitant therapy (93.0%; 95% CI, 88.3%-97.7%)(P = .83). Per-protocol eradication results were similar for sequential (93.1%; 95% CI, 90.7%-95.5%) and concomitant therapy (93.0%; 95% CI, 88.3%-97.7%) (P = .99). Univariate analysis showed that compliance and resistance to clarithromycin were independent determinants of eradication. Dual resistance did not influence the level of eradication in the concomitant group, but significantly affected that of the sequential therapy group. Clarithromycin resistance was less frequent than expected.

CONCLUSIONS

Sequential or concomitant therapy with a PPI, amoxicillin, clarithromycin, and an imidazole agent are equally effective and safe for eradication of H pylori infection. Resistance to clarithromycin, compliance, and adverse events reduced the level of eradication. Concomitant therapy may be more suitable for patients with dual resistance to antibiotics.

Short-term celecoxib intervention is a safe and effective chemopreventive for gastric carcinogenesis based on a Mongolian gerbil model

AIM

To evaluate the optimal intervention point of a selective cyclooxygenase-2 (COX-2) inhibitor, celecoxib, for inhibiting Helicobacter pylori (H. pylori)-associated gastric carcinogenesis in Mongolian gerbils (MGs).

METHODS

One hundred and twelve MGs were divided into six groups (A-F). One hundred gerbils were inoculated with H. pylori (groups A-E). Twelve gerbils were inoculated with vehicle broth only (group F). After 4 wk, they were given N'-methyl-N'-nitro-N-nitroso-guanidine (MNNG) (50 microg/mL) in the drinking water for 20 wk. In groups B-E, the animals were given the stock celecoxib (10 mg/kg per day) diet from the 21st, 31st, 21st and 41st week respectively. The periods of administering celecoxib were 30, 20, 20, and 15 wk respectively. On the 51st week, the animals were sacrificed for histological examination. Local PCNA expression was examined by the immunohistochemistry method. The expression of COX-2 protein was assessed by western blot. Analysis used the chi(2) test. The difference was regarded as significant when P value was less than 0.05.

RESULTS

Seventeen percent (17/100) of H. pylori-infected MGs developed gastric cancer. All of these lesions were well-differentiated adenocarcinoma. The incidence rates of adenocarcinoma in groups A-F were 40%, 0%, 0%, 20%, 25%, and 0% respectively. The inflammatory scores were higher in group B than in other groups. There was no inflammatory response noted in group F. Celecoxib treatment resulted in a significant reduction in the proliferation of H. pylori-infected mucosal cells (groups B, C and D) (P < 0.01). The expression of COX-2 protein was significantly attenuated in the groups which were celecoxib-treated for more than 20 wk (groups B, C, D). The groups treated with celecoxib had a significantly lower rate of advanced gastric cancer (34% vs 75%, P < 0.001) There were no sudden deaths in any of the groups.

CONCLUSION

Short-term treatment with celecoxib has an anti-carcinogenic effect, and resulted in less severe inflammation and inhibited the invasive degree of gastric cancer.

Furazolidone, co-amoxiclav, colloidal bismuth subcitrate, and esomeprazole for patients who failed to eradicate Helicobacter pylori with triple therapy

There is increasing evidence of Helicobacter pylori (H. pylori) resistance to the classical triple therapy consisting of a proton-pump inhibitor and clarithromycin with either amoxicillin or metronidazole. This study is aimed at establishing the efficacy and safety of a 14-day regimen to eradicate H. pylori in patients who have failed with the classical triple therapy given for 14 days. One hundred seventy-six patients diagnosed to have H. pylori infection were given triple therapy for 14 days. Fifty-two patients who failed to respond as evident from positive 14C-urea breath test (UBT) done 4-6 weeks after the completion of triple therapy were offered a combination regimen comprised of furazolidone 200 mg b.i.d, co-amoxiclav 1 g b.i.d., colloidal bismuth subcitrate 240 mg b.i.d., and esomeprazole 40 mg b.i.d. for 14 days. The mean age of these patients was 41 +/- 13 years (range 20-67). Thirty-four were males. To document eradication of H. pylori, UBT was repeated 4 weeks after the completion of treatment. On an intention-to-treat analysis, the eradication rate was 81% (42 out of 52) whereas on per-protocol basis, the eradication rate was 82.4% (42 out of 51). In conclusion, this new regimen represents a suitable second-line therapy.

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

OBJECTIVES

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Helicobacter pylori binding to new glycans based on N-acetyllactosamine

Previously we reported binding of Helicobacter pylori to various nonacid and sialylated neolacto carbohydrate structures using a wide range of natural and chemically modified sequences. A novel nonsialylated neolacto-based binding epitope, GlcNAc beta 3Gal beta 4GlcNAc, and analogous structures carrying terminal GalNAc beta 3, GalNAc alpha 3, or Gal alpha 3 showed the binding activity (Miller-Podraza H, Lanne B, Angström J, Teneberg S, Abul-Milh M, Jovall P-A, Karlsson H, Karlsson K-A. 2005. Novel binding epitope for Helicobacter pylori found in neolacto carbohydrate chains. J Biol Chem. 280:19695-19703). The present work reports two other H. pylori-binding nonsialylated neolacto-based structures, GlcA beta 3Gal beta 4GlcNAc beta 3-R and Glc beta 3Gal beta 4GlcNAc beta 3-R, and two amide derivatives (N-methyl and N-ethyl) of GlcA beta 3Gal beta 4GlcNAc beta 3-R which were bound by H. pylori. The latter structures turned out to be more effective as H. pylori binders than the parent saccharide. New reducing-end variants of the neolacto epitope including species containing N-acetyllactosamine linked beta 6 to GlcNAc or Gal with similarity to branched polylactosamines and mucins were prepared and tested. The results extend our previous findings on binding specificities of H. pylori and show that this pathogen is able to interact with an array of N-acetyllactosamine/neolacto structures, which may be of importance for the in vivo interaction of the bacterium with human cells. The information gained in this work may also be of value for rational design of anti-H. pylori drugs.

Cytotoxin-associated Gene-A-positive Helicobacter pylori strains infection increases the risk of recurrent atherosclerotic stroke

BACKGROUND

CagA-positive Helicobacter pylori infection has been found to be associated with a first-ever atherosclerotic stroke. The aim of this study was to investigate whether these strains represent an independent risk factor for recurrent atherosclerotic stroke.

MATERIALS AND METHODS

We performed a longitudinal study of patients with a first-ever large vessels stroke and resulted positive at H. pylori serology. Patients had clinical examination 1 month after the acute event, and were subsequently visited or contacted by telephone up to 3 years at 6-month intervals. Sera obtained at the time of enrollment were frozen and analyzed for the presence of anti-CagA antibodies at the end of the study. The primary outcome event was any fatal or nonfatal stroke after the index stroke.

RESULTS

One hundred seventy H. pylori-positive patients were included (n = 68 CagA positive and n = 102 CagA negative). No significant difference regarding age and other stroke risk factors was detected. According to Kaplan-Meier survival analysis, CagA-positive patients showed a significantly higher risk for stroke recurrence than CagA-negative ones (45.6% vs 17.6%; p < .001). Difference in the rate of recurrent stroke between the two groups persisted after Cox regression analysis taking into account possible confounding factors (hazard ratio = 3.5; 95% CI = 1.9-6.4; p < .001).

CONCLUSIONS

Infection with H. pylori CagA-positive strains increases the risk of recurrent atherosclerotic stroke. Seropositivity determination should be performed in order to identify high-risk patients requiring a strict clinical surveillance, and the possible beneficial effect of eradication therapy should be evaluated.

Comparison of short- and long-term treatment protocols and the results of second-line quadruple therapy in children with Helicobacter pylori infection

BACKGROUND

Research regarding the optimal therapeutic approach to Helicobacter pylori infection in children is ongoing. There is no consensus as to duration of treatment or second-line therapy. The purpose of this study was compare the efficacy of 7-day and 14-day triple therapies and report the results of second-line quadruple therapy in children.

METHODS

A total of 275 consecutive H. pylori-infected patients were enrolled into two groups. Group 1 (n = 180) received triple therapy with 14 days of amoxicillin and clarithromycin and 21 days of proton pump inhibitor. Group 2 (n = 95) received triple therapy including 7 days of amoxicillin and clarithromycin with 21 days of proton pump inhibitor. Subsequently, 89 patients not responding to the triple therapies received quadruple therapy comprising omeprazole (14 days), bismuth subcitrate (7 days), doxycycline (7 days), and metronidazole (7 days). Eradication was evaluated by 13C-urea breath test.

RESULTS

The per-protocol eradication rates in groups 1 and 2 were 60.5% and 55.8%, respectively (P = 0.44). In the second interview with 227 patients, severe symptoms were reported to have disappeared in 59% and decreased notably in 34.8%. Helicobacter pylori was eradicated in 66.7% of patients at the end of the quadruple therapy. In the third interview with 75 patients, severe symptoms had decreased in 38.6% and disappeared in 56%.

CONCLUSIONS

The different duration of the two treatment regimens had no impact on eradication rates. Furthermore, quadruple therapy was necessary to achieve H. pylori eradication after triple therapy. However, the eradication rate with quadruple therapy was still insufficient. Consequently, a new therapeutic approach to H. pylori infection in children is needed.

Nodular gastritis in adults: clinical features, endoscopic appearance, histopathological features, and response to therapy

BACKGROUND AND AIMS

The present study aims to determine the prevalence of nodular gastritis (NG) and ascertain its clinical presentation and histopathological features in adults. It also assesses its association with Helicobacter pylori and the normalization of endoscopic features, symptoms, and histology after anti H. pylori therapy.

METHODS

A total of 7140 patients undergoing upper gastrointestinal endoscopy were studied. Patients showing nodularity of the gastric mucosa at endoscopy and an age- and sex-matched control group with normal gastric mucosa underwent biopsies from the gastric antrum and fundus. The biopsies were assessed for the presence of mucosal inflammation, activity, eosinophils, atrophy, lymphoid follicles, H. pylori, and the presence of intestinal metaplasia. Patients with NG were given triple therapy. Endoscopy and biopsy was repeated after 4 weeks of stopping therapy. The symptoms of the patients and histology were assessed pre- and post-therapy.

RESULTS

Thirty-two patients with an age range of 20-65 years presenting with NG and 40 age- and sex-matched controls were included in the study. Presenting symptoms were epigastric pain (56%), nausea (75%), vomiting (50%) and abdominal bloating (62.5%). All these symptoms regressed significantly after 2 week of triple therapy against H. pylori. A marked improvement in histopathological features was seen post-therapy where the presence of lymphoid aggregates, eosinophils in the mucosa, atrophy, and intestinal metaplasia improved significantly (P < 0.05) after therapy, as compared to the control group of patients.

CONCLUSION

The symptoms of NG and endoscopic features regress significantly after H. pylori therapy with a proton pump inhibitor and two antibiotics and should routinely be given to treat this form of gastritis. This may prevent progression to further complications.

Dynamic colonization of Helicobacter pylori in human gastric mucosa

OBJECTIVE

To investigate the dynamic behaviour of Helicobacter pylori in the colonization of the human gastric mucosa in patients previously treated for H. pylori infection.

MATERIAL AND METHODS

Twenty-one dyspeptic patients were included in the study. Biopsies from each individual were taken and analysed for H. pylori detection using cultural, molecular and ultrastructural methods.

RESULTS

Through culture, H. pylori was isolated in 7 out of 21 patients and the detection of the minimum inhibitory concentration (MIC) against drugs commonly used in H. pylori therapy revealed a susceptibility panel in which only one strain was multidrug resistant. By studying the expression of the H. pylori glmM constitutive gene, viable H. pylori cells were detected in 19 out of 21 analysed biopsies. In these positive cases, the expression of the Quorum-Sensing related gene, luxS, was always detected. The analysis of glmM and luxS sequences confirmed the H. pylori identity. Scanning electron microscopy (SEM) analysis of biopsies from patients harbouring culturable bacteria showed a prevalent "S-shape" H. pylori morphotype co-existent with coccoid aggregated bacteria embedded in an abundant matrix; while samples from patients shown as H. pylori-positive only through the molecular method showed clustered coccoid bacteria arranged in a microbial biofilm.

CONCLUSIONS

In the present work we describe a new scenario in H. pylori mucosa colonization suggesting, in infection recalcitrance, the planning of more efficacious protocols in order also to identify camouflaged and protected clustered bacteria, taking into account this serious microbial problem in medicine in the recommendation of therapeutic regimens.

Interpretation of the 13C-urea breath test in the choice of second- and third-line eradication of Helicobacter pylori infection

BACKGROUND

The urea breath test (UBT) is one of the most accurate methods of assessing Helicobacter pylori status. The predictive value of the test is, however, uncertain. This study was a serial, prospective analysis of the change over time of UBT values after first-, second- and third-line treatments of patients with failed eradication therapy.

METHODS

One hundred thirty-four duodenal ulcer patients with persisting H. pylori infection after first-line triple therapy were enrolled in a cross-over manner to receive either pantoprazole (40 mg twice daily), amoxicillin (1000 mg twice daily), and clarithromycin (500 mg) or ranitidine bismuth citrate (400 mg twice daily), metronidazole (250 mg twice daily), and clarithromycin (500 mg twice daily) for 7 days. Forty-one patients with failed second-line treatment were randomized to receive third-line quadruple therapies with pantoprazole + amoxicillin and tetracycline (500 mg four times daily) and either nitrofurantoin (100 mg three times daily) or bismuth subsalicylate (120 mg four times daily). Breath tests were performed 6 weeks after therapy. The delta(13)CO(2) values ( per thousand) after primary, secondary, and tertiary treatment were analyzed, and the correlation between pretreatment values and the rate of H. pylori eradication was assessed.

RESULTS

In patients with successful second-line treatment, UBT values decreased from 12.4 per thousand [confidence interval (CI), 9.7-15.7)] to 2.8 per thousand (CI, 0.9-2.5) (P=0.001), and in those with persistent infection, they increased from 13.2 per thousand (CI, 7.3-19.1) to 19.2 per thousand (CI, 13.4-25.0) (P=0.03). After a failed quadruple regimen, UBT values increased from 19.3 per thousand (CI, 16.2-22.4) to 25.8 per thousand (CI, 19.8-312.8) (P=0.03). The correlation between the pretreatment UBT values and the rate of eradication was negative for both second- and third-line therapies.

CONCLUSIONS

Serial assessment showed that UBT values after successive treatments showed a marked tendency to increase over time in failed cases. The significance of this phenomenon must be further studied. It might indicate increased colonization, ongoing resistance, or urease gene overexpression. Higher pretreatment UBT values were associated with lower (<60%) eradication rates. In these cases, alternative/rescue therapies should be chosen.

Is a 7-day Helicobater pylori treatment enough for eradication and inactivation of gastric inflammatory activity?

AIM: To compare the efficacy of a 7-d vs 10-d triple therapy regarding H pylori eradication, endoscopic findings and histological gastric inflammatory inactivation in the Ecuadorian population.

METHODS: 136 patients with dyspepsia and H pylori infection were randomized in 2 groups (68 per group): group 1, 7-d therapy; group 2, 10-d therapy. Both groups received the same medication and daily dosage: omeprazole 20 mg bid, clarithromycin 500 mg bid and amoxicillin 1 g bid. Endoscopy was performed for histological assessment and H pylori infection status before and 8 wk after treatment.

RESULTS: H pylori was eradicated in 68% of group 1 vs 83.8% of group 2 for the intention-to-treat analysis (ITT) (P = 0.03; OR = 2.48; 95% CI, 1.1-5.8), and 68% in group 1 vs 88% in group 2 for the per-protocol analysis (PP) (P = 0.008; OR = 3.66; 95% CI, 1.4-10). Endoscopic gastric mucosa normalization was observed in 56.9% in group 1 vs 61.2% in group 2 for ITT, with similar results for the PP, the difference being statistically not significant. The rate of inflammatory inactivation was 69% in group 1 vs 88.7% in group 2 for ITT (P = 0.007; OR = 3.00; 95% CI, 1.2-7.5), and 69% in group 1 vs 96% in group 2 for PP (P = 0.0002; OR = 7.25; 95% CI, 2-26).

CONCLUSION: In this Ecuadorian population, the 10-d therapy was more effective than the 7-d therapy for H pylori eradication as well as for gastric mucosa inflammatory inactivation.

Structure-based inhibitors exhibit differential activities against Helicobacter pylori and Escherichia coli undecaprenyl pyrophosphate synthases

Helicobacter pylori colonizes the human gastric epithelium and causes diseases such as gastritis, peptic ulcers, and stomach cancer. Undecaprenyl pyrophosphate synthase (UPPS), which catalyzes consecutive condensation reactions of farnesyl pyrophosphate with eight isopentenyl pyrophosphate to form lipid carrier for bacterial peptidoglycan biosynthesis, represents a potential target for developing new antibiotics. In this study, we solved the crystal structure of H. pylori UPPS and performed virtual screening of inhibitors from a library of 58,635 compounds. Two hits were found to exhibit differential activities against Helicobacter pylori and Escherichia coli UPPS, giving the possibility of developing antibiotics specially targeting pathogenic H. pylori without killing the intestinal E. coli.

Does HIV infection alter the incidence or pathology of Helicobacter pylori infection?

Gastrointestinal (GI) discomfort is a common complaint among patients infected with HIV. GI symptoms can be caused by a myriad of factors including but not limited to coinfections, antiretroviral therapy, medications for opportunistic infections, and nutritional status. Some researchers have hypothesized that Helicobacter pylori infection may be more common among HIV-infected patients as a result of immune suppression. An increased incidence of H. pylori infection would contribute to the prevalence of GI complaints in this population. Several epidemiologic studies have examined the relationship between H. pylori infection and HIV. While studies have generally reported conflicting results that may be related to the use of varied study designs, some identifiable patterns can be discerned. It does appear that the incidence of H. pylori infection is lower among patients with AIDS compared to matched HIV-infected and -uninfected controls. This review discusses the various epidemiologic trials that have been conducted in this area and describes the potential physiologic mechanisms to explain these findings. The clinical applicability of these studies as well as limitations are also discussed. A greater number of well-designed and controlled trials are needed before any definitive conclusions regarding these diseases can be made, until such time clinicians should be aware of the potential issues regarding H. pylori screening and management in the context of HIV. Research in this area might also provide information relating to HIV-associated GI changes and the role of these changes in HIV pathogenesis.

Rabeprazole- versus esomeprazole-based eradication regimens for H. pylori infection

BACKGROUND

Different kinds of proton pump inhibitor-based triple therapies could result in different Helicobacter pylori eradication rates.

AIM

The aims of this study were to compare the efficacy and safety of rabeprazole- and esomeprazole-based triple therapy in primary treatment of H. pylori infection in Taiwan.

PATIENTS AND METHODS

From June 2005 to March 2007, 420 H. pylori-infected patients were randomly assigned to receive a 7-day eradication therapy with either esomeprazole 40 mg daily (EAC group, n = 209) or rabeprazole 20 mg b.i.d. (RAC group, n = 211) in combination with amoxicillin 1 g b.i.d. and clarithromycin 500 mg b.i.d.. Follow-up endoscopy with biopsy was done 12-16 weeks after completion of eradication therapy. Those who refused endoscopic exams underwent (13)C-urea breath test to assess the treatment response.

RESULTS

Intention-to-treat analysis revealed that the eradication rate was 89.4% in the EAC group and 90.5% in RAC groups (p-value = .72). All of the subjects returned for assessment of compliance (100% in EAC group vs. 99.5% in RAC group, p-value = .32) and adverse events (3.83% in EAC group vs. 6.16% in RAC group, p-value = .27). Sixty (28.7%) and 37 (17.6%) patients in EAC and RAC group, respectively, refused endoscopy and underwent a (13)C-urea breath test to determine the treatment effect.

CONCLUSION

In conclusion, rabeprazole- and esomeprazole-based primary therapies for H. pylori infection are comparable in efficacy and safety.

Nitrofuran-based regimens for the eradication of Helicobacter pylori infection

Several aspects of Helicobacter pylori eradication have been meta-analyzed; however, nitrofuran-based therapies constitute an exception. The aim of this study was the systematic review and meta-analysis of the effect of furazolidone- and nitrofurantoin-based regimens in the eradication of infection. Studies evaluating the effects of nitrofurans on H. pylori were identified from Medline, EMBASE, the Cochrane Controlled Trials Register and congress abstracts. The studies were classified into groups based on first-, second- and third-line regimens. The pooled eradication rates and combined odd ratios of the individual studies were calculated and compared with the published meta-analysis. The factors influencing the efficiency of the regimens were also analyzed. Side-effects of nitrofuran-based regimens were also analyzed. The pooled eradication rate of primary proton pump inhibitor-based regimens containing furazolidone was 76.3% (CI 67.8-84.2). The odds ratio for furazolidone-based regimens versus standard triple therapies was 2.34 (CI 0.76-3.92). Ranitidine bismuth citrate + furazolidone-based triple regimens were equally efficient (83.5%, CI 74.0-93.0, P = 0.06 versus triple therapies). Schedules including a H(2) antagonist + furazolidone + one other antibiotic achieved pooled eradication rates of 79.9% (CI 67.8-89.9, P = 0.04). Bismuth-based triple therapies achieved 84.5% (CI 72.6-93.0, P = 0.002). Primary quadruple regimens containing furazolidone were superior to triple therapies (83.4%, CI 69.7-92.3, P = 0.01). Second-line schedules containing furazolidone obtained eradication rates of 76.1% (CI 66.4-85.0, P = 0.28 versus primary regimens). Third-line 'rescue' therapies were efficient in 65.5% of the cases (CI 56.3-75.5, P = 0.0001). Side-effects of the regimens containing furazolidone were more frequent than in standard therapies (P = 0.02). The combined odds ratio of side-effects for furazolidone-based versus standard therapies was 0.74 (CI 0.32-1.98). The duration of treatment, but not the furazolidone dose, influenced the treatment outcome. Primary triple regimens containing furazolidone are slightly less efficient than the standard primary combinations; primary quadruple regimens were more efficient than triple therapies. Furazolidone is also efficient as a component of second-line or rescue therapies.

High-dose versus low-dose esomeprazole-based triple therapy for Helicobacter pylori infection

BACKGROUND

This prospective, randomized, controlled study was conducted to compare the efficacies of high-dose and low-dose esomeprazole-based triple therapies for Helicobacter pylori eradication in Taiwan.

MATERIALS AND METHODS

From January 2004 to June 2006, 240 H. pylori-infected patients were randomly assigned to undergo high-dose (40 mg b.d.) or low-dose (40 mg o.d.) esomeprazole combined with clarithromycin (500 mg b.d.) and amoxicillin (1 g b.d.) for one week. Follow-up endoscopy was performed at eight weeks after the end of treatment to evaluate the response to therapy.

RESULTS

Intention-to-treat analysis demonstrated no differences between eradication rates of high-dose and low-dose groups (92% vs. 90%, respectively, P > 0.05). Per-protocol analysis yielded comparable results (95% vs. 93%). Both groups exhibited similar frequencies of adverse events (13% vs. 11%) and drug compliance (96% vs. 93%). Multivariate analysis indicated that only good compliance (odds ratio: 10.3, 95% CI, 3.0-35.7) was an independent predictor of treatment success.

CONCLUSIONS

This work demonstrates that low-dose esomeprazole-based triple therapy yields a similar eradication rate as high-dose esomeprazole-based therapy in Taiwan. Since the cost of the low-dose regime is lower than that of the high-dose regime, low-dose esomeprazole-based triple therapy can reasonably be recommended for the first-line eradication of H. pylori for Taiwanese and probably most Asians.

The Hungarian epidemiology of clarithromycin resistance in Helicobacter pylori infection

Az antibiotikum-érzékenység az eradikációs kezelés sikerének fontos meghatározója. Célkitűzés: A dolgozat célja a clarithromycin-rezisztencia gyakoriságának meghatározása és a magyarországi adatok áttekintése. Módszer: A) Gasztroenterológiai szakrendelésen vizsgált 238, véletlenszerűen kiválasztott eset biopsziás anyagából fluoreszcens in situ hibridizációval határozták meg a Helicobacter pylori törzs elsődleges és másodlagos clarithromycin-rezisztenciájának gyakoriságát és annak összefüggését a demográfiai adatokkal. B) Az 1995–2006 közötti irodalomból meghatározták a chlarithromycin-rezisztencia gyakoriságát, jellegét és időbeli változását. C) Elemezték a clarithromycin forgalmi adatait. Eredmények: A) A primer clarithromycin-rezisztencia gyakorisága 17,3%, amely az esetek 47,4%-ában teljes, 52,6%-ban részleges. A másodlagos rezisztencia gyakorisága 55,5%-os. A primer rezisztencia és az életkor ( r = 015), női nem ( r = 0,10) és a dohányzás ( r = 0,16) között gyenge, de pozitív összefüggést észleltek. B) A hazai irodalomban 8 dolgozatban 775 betegben mérték fel az antibiotikum-érzékenységet. A fenotípusmódszerekkel észlelt elsődleges rezisztencia 3,9%, míg fluoreszcens in situ hibridizációval országosan 17,0%-os rezisztenciát észleltek. Az eredmények között regionális különbségek vannak. A másodlagos rezisztencia országos aránya 53,5% fenotípus-, 49% genotípusmódszerrel. C) 1993 és 2005 között a clarithromycin forgalma ötszörösére emelkedett. Megbeszélés: A fluoreszcens in situ hibridizációval vizsgált primer rezisztencia hazai prevalenciája lényegesen magasabb a fenotípusmódszerek arányánál. A jelenség feltételezhetően összefügg a makrolidok fokozott használatával.

Optimal length of triple therapy for H pylori eradication in a population with high prevalence of infection in Chile

AIM: To compare the efficacy of 7-d versus 14-d triple therapy for the treatment of H pylori infection in Chile, with a prevalence of 73% in general population.

METHODS: H pylori-infected patients diagnosed by rapid urease test, with non-ulcer dyspepsia or peptic ulcer disease were randomized to receive omeprazole 20 mg bid, amoxicillin 1 g bid, and clarithromycin 500 mg bid for 7 (OAC7) or 14 (OAC14) d. Primary outcome was eradication rate 6 wk after the treatment. Subgroup analysis was carried out considering the eradication rate among patients with or without peptic ulcer disease and eradication rate among smokers or non-smokers.

RESULTS: One hundred and thirty-one patients were randomized to OAC7 (n = 69) or OAC14 (n = 62). The overall eradication rate (intention-to-treat) was 78.3% in OAC7 and 85.5% in OAC14 groups, without a significant difference (P =0.37). No significant difference in the eradication rate was found among the patients with peptic ulcer disease (n = 31) between the OAC7 group (85.7%) and OAC14 group (87.5%). However, smokers had an obviously lower eradication rate compared to non-smokers, particularly in the OAC7 group (57.1% in smokers vs 83.6% in non-smokers; P = 0.06). Adverse effects rate were similar between both groups.

CONCLUSION: Short-term efficacy of triple therapy with OAC for 7 d is comparable to 14 d in this high-prevalence population. Longer follow-up, and studies focused to some subgroups of patients (smokers and non-ulcer patients) are necessary to support widespread use of 7-d instead of 10-14-d triple therapy in a developing country like Chile.

A curcumin-based 1-week triple therapy for eradication of Helicobacter pylori infection: something to learn from failure?

BACKGROUND

Curcumin is the principal element of turmeric powder extracted from the root of Curcuma longa. Studies on curcumin have demonstrated some anti-Helicobacter pylori activity as well as immunomodulating properties. N-acetylcysteine and lactoferrin with their respective mucolytic and antibacterial activities might also be effective in H. pylori eradication therapy.

AIM

To determine if a 7-day non-antibiotic therapy comprised of curcumin, lactoferrin, N-acetylcysteine, and pantoprazole was effective for eradication of H. pylori infection and reduction of gastric inflammation, assessed by serum pepsinogens and relief of symptoms.

SUBJECTS AND METHODS

Twenty-five consecutive H. pylori-positive patients (12 males, mean age 50 +/- 12 years, range 31-76) with functional dyspepsia were enrolled. Patients were administered for 7 days curcumin 30 mg b.i.d., bovine lactoferrin 100 mg b.i.d., N-acetylcysteine 600 mg b.i.d., and pantoprazole 20 mg b.i.d. H. pylori status and upper gastrointestinal symptoms were assessed by (13)C-urea breath test and a scale of upper gastrointestinal symptoms intensity (absent, mild, moderate, and severe), as well as a blood test for serum pepsinogens (sPGI, sPGII), gastrin-17 (G-17), and anti-H. pylori IgG (IgG-Hp) at baseline (T0) and after 2 months (T1).

RESULTS

Three of 25 patients (12%) were cured of H. pylori infection. A significant decrease in the overall severity of symptoms (T0: 6, interquartile range [IQR]: 4.5-8; T1: 2, IQR: 2-3; p < or = .001), and sPGII (T0: 16 microg/L, IQR: 13-22; T1: 10 microg/L, IQR: 8-16; p < or = .001) and sPGI (T0: 82 microg/L, IQR: 67-97; T1: 74 microg/L, IQR: 62-94; p = .02) levels were observed after 2 months of the treatment. IgG and G-17 values did not significantly decrease after 2 months.

CONCLUSIONS

This novel therapy was not effective for H. pylori eradication. However, despite the bacterium persistence, significant improvement of dyspeptic symptoms and reduction of serologic signs of gastric inflammation were observed after 2 months at the end of the 7-day treatment schedule.

Bismuth-norfloxacin complex: Synthesis, physicochemical and antimicrobial evaluation

Norfloxacin is a fluoroquinolone antibacterial agent which is active against various Gram-positive as well as Gram-negative microorganisms. Presence of metal ions considerably alters the activity of fluoroquinolones against potentially susceptible bacteria. As bismuth is known to possess a good antibacterial activity, bismuth complex of norfloxacin was prepared by reacting bismuth citrate with aqueous solution of norfloxacin. The structure of the bismuth-norfloxacin complex (BNC) was confirmed by spectral, chemical and elemental analysis. Antimicrobial studies were carried out using agar diffusion method against Escherichia coli (ATCC 25922), Klebsiella pneumoniae (NTCC 10320), Staphylococcus aureus (ATCC 29213), Bacillus pumilis (NTCC 8241) and Staphylococcus epidermidis (ATCC 12228). The results showed significant increase (p<0.05, Tukeys test) in antibacterial activity of BNC as compared with norfloxacin and physical mixture of norfloxacin and bismuth citrate. This increase in activity is being considered due to increased bioavailability of the metal drug complex. Thus, the use of the BNC may be preferable over norfloxacin alone.

Anti-microbial photodynamic therapy: useful in the future?

Previous chapters in this volume have focused on fundamental principles and clinical applications of PDT. This chapter will attempt to outline emerging areas of research to identify some new applications that may become useful in the future in clinical practise. The worldwide rise in antibiotic resistance has driven research to the development of novel anti-microbial strategies. Cutaneous diseases caused by MRSA are ideally suited to treatment by anti-microbial photodynamic therapy for eradicating localized infections and for modulating wound healing due to the ability to deliver photosensitizer and light with topical application. The use of photosensitizer and light as an anti-microbial agent against periodontal microbial biofilms should also represent an attractive method of eliminating oral bacteria. Suitable light sources, laser light and non-coherent light will be briefly covered. This chapter will focus on some aspects of anti-microbial photodynamic therapy that appear to be promising for dermatological indications and inactivation of pathogenic bacteria within the oral cavity.

Pharmacoeconomic comparison of Helicobacter pylori eradication regimens

BACKGROUND

Helicobacter pylori is the most important etiologic agent for development of peptic ulcer, chronic gastritis and gastric carcinomas. It is now well established that H. pylori eradication treatment is more cost-effective than acid suppressing therapies alone for the treatment of peptic ulcer disease. However, the comparative cost-effectiveness of various H. pylori eradication regimens is still not clear.

OBJECTIVE

This study was designed to make a pharmacoeconomic comparison of different H. pylori eradication regimens in patients with peptic ulcer disease or chronic gastritis, using real-world cost and effectiveness data.

SETTING

Istanbul University Hospital and Marmara University Hospital.

METHOD

A total of 75 patients diagnosed as H. pylori (+) by endoscopy were randomized to receive one of the seven H. pylori treatment protocols. These protocols were as follows: (LAC) = 'lansoprazole 30 mg bid + amoxicillin 1 g bid + clarithromycin 500 mg bid' for 7 days and (OCM) = 'omeprazole 20 mg bid + clarithromycin 250 mg bid + metronidazole 500 mg bid'; (OAM) = 'omeprazole 40 mg qd + amoxicillin 500 mg tid + metronidazole 500 mg tid'; (MARB) = 'metronidazole 250 mg tid + amoxicillin 500 mg qid + ranitidine 300 mg hs + bismuth 300 mg qid'; (OAC) = omeprazole 20 mg bid + amoxicillin 1 g bid + clarithromycin 500 mg bid'; (OCA) = omeprazole 40 mg bid + clarithromycin 500 mg bid + amoxicillin 1 g bid'; (OAB) = 'omeprazole 20 mg bid + amoxicillin 500 mg tid + bismuth 300 mg qid' each for 14 days. Only direct costs were included in the analysis. Effectiveness was measured in terms of "successful eradication". The cost-effectiveness ratios of the regimens were calculated using these effectiveness and cost data. The perspective of the study was assumed as the Government's perspective.

MAIN OUTCOME MEASURE

Cost-effectiveness ratios of eradication regimens.

RESULTS

MARB and OCA regimens were found to be more cost-effective than the other treatment regimens. The eradication rates and cost-effectiveness ratios calculated for these protocols were 90% (158.7 euros) for MARB and 90% (195.8 euros) for OCA regimen.

CONCLUSION

This study confirms the importance of using local pharmacoeconomic data. Analyses such as this give decision-makers the tools to choose a better treatment option which is both highly effective yet and has a low cost.

Furazolidone-based triple therapy for H pylori gastritis in children

AIM: To evaluate the furazolidone-based triple therapy in children with symptomatic H pylori gastritis.

METHODS: A prospective and consecutive open trial was carried out. The study included 38 patients with upper digestive symptoms sufficiently severe to warrant endoscopic investigation. H pylori status was defined based both on histology and on positive ¹³C-urea breath test. Drug regimen was a seven-day course of omeprazole, clarithromycin and furazolidone (100 mg, 200 mg if over 30 kg) twice daily. Eradication of H pylori was assessed two months after treatment by histology and ¹³C-urea breath test. Further clinical evaluation was performed 7 d, 2 and 6 mo after the treatment.

RESULTS: Thirty-eight patients (24 females, 14 males) were included. Their age ranged from 4 to 17.8 (mean 10.9 ± 3.7) years. On intent-to-treat analysis (n = 38), the eradication rate of H pylori was 73.7% (95% CI, 65.2%-82%) whereas in per-protocol analysis (n = 33) it was 84.8% (95% CI, 78.5%-91%). All the patients with duodenal ulcer (n = 7) were successfully treated (100% vs 56.2% with antral nodularity). Side effects were reported in 26 patients (68.4%), mainly vomiting (14/26) and abdominal pain (n = 13). Successfully treated dyspeptic patients showed improvement in 78.9% of H pylori-negative patients after six months and in 50% of H pylori-positive patients after six months of treatment.

CONCLUSION: Triple therapy with furazolidone achieves moderate efficacy in H pylori treatment. The eradication rate seems to be higher in patients with duodenal ulcer.

First-line eradication of H pylori infection in Europe: a meta-analysis based on congress abstracts, 1997-2004

AIM

To meta-analyse the European abstracts presented between 1997-2004 at the European H pylori Study Group, United European Gastroenterology Week meetings and World Congresses of Gastroenterology.

METHODS

The abstracts of randomized/controlled prospective studies were classified into groups based on first-line eradication schedules. The quality of the abstracts was checked by a validated score system. The pooled eradication rates (PER) and combined odds ratios (OR) were calculated and compared with the published meta-analyses.

RESULTS

The PER of proton pump inhibitor-based (PPI) one week triple therapies was 81.4% (confidence interval, 95% CI: 78.5-84.5). Ranitidine bismuth citrate-based (RBC) triple regimens have an efficiency rate of 78.5% (95% CI: 70.5%-84.3%) (P = 0.28 vs PPI). The OR for PPI effect vs RBC regimens was 1.1 (95% CI: 0.92-1.30). H(2) receptor antagonist-based triple therapies achieved 64.1% (95% CI: 52.6-75.6) (P = 0.02 < 0.05 vs PPI), the OR vs PPI regimens was 1.55 (95% CI: 0.72-3.78). PPI-based double combinations were less efficient than triple regimens (PER: 55.0%, OR: 4.90, 95% CI: 2.36-9.70). Quadruple regimens were successful in 82.6% (95% CI: 76.0-89.7), the OR vs triple therapies was 0.80 (0.62-1.03). Clarithromycin + amoxicillin or nitroimidazole combinations were efficient in 80.5% (95% CI: 77.2-84.2) and 83.8% (95% CI: 81.7-85.9), respectively. Amoxicillin + nitromidazole therapies eradicated the infection in 73.5% (66.6-78.5) (P = 0.01 < 0.05 vs clarithromycin-based regimens).

CONCLUSION

PPI/RBC-based triple therapies achieved comparable results with the meta-analyses. H(2)-receptor antagonists and PPI-based double combinations were less efficient. Triple and quadruple regimens were equally effective. Clarithromycin + either amoxicillin or nitroimidazole containing regimens were more effective than amoxicillin + nitroimidazole combinations. High quality congress abstracts constitutes a valuable pool of data which is suitable for meta-analytical workup.

Sequential therapy using high-dose esomeprazole-amoxicillin followed by gatifloxacin for Helicobacter pylori infection

BACKGROUND

The success rate of current anti-Helicobacter pylori triple therapies in now generally 80% or less. Sequential therapy has proved superior.

AIM

To test a new sequential therapy for H. pylori eradication.

METHODS

This was a pilot study of a sequential therapy consisting of 40 mg of esomeprazole and 1 g amoxicillin t.d.s., for 12 days. On days 6 through 12 gatifloxacin (400 mg in the morning) was added. Outcome was accessed 4 or more weeks after ending antibiotic therapy. Both naive and treatment failures were eligible.

RESULTS

Thirty patients were entered in the study. One was lost to follow-up and one stopped early because of side effects. The success rate intention-to-treat was 80% (95% CI: 61-92%). The per-protocol eradication rate was 85.7% (95% CI: 67-95%); two of the four failures had pre-treatment gatifloxacin-resistant H. pylori. Side effects were reported by 13 patients (46%) and were generally mild with diarrhoea being most common (n = 6). Only one patient stopped medicine because of side effects of dizziness (severe) and diarrhoea (mild).

CONCLUSIONS

Sequential therapy using the combination of a high dose of proton-pump inhibitor and amoxicillin followed gatifloxacin was effective, but pre-treatment susceptibility testing may become necessary as fluoroquinolone resistance increases.

Pathogenesis of Helicobacter pylori Infection

SUMMARY

Helicobacter pylori is the first formally recognized bacterial carcinogen and is one of the most successful human pathogens, as over half of the world's population is colonized with this gram-negative bacterium. Unless treated, colonization usually persists lifelong. H. pylori infection represents a key factor in the etiology of various gastrointestinal diseases, ranging from chronic active gastritis without clinical symptoms to peptic ulceration, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Disease outcome is the result of the complex interplay between the host and the bacterium. Host immune gene polymorphisms and gastric acid secretion largely determine the bacterium's ability to colonize a specific gastric niche. Bacterial virulence factors such as the cytotoxin-associated gene pathogenicity island-encoded protein CagA and the vacuolating cytotoxin VacA aid in this colonization of the gastric mucosa and subsequently seem to modulate the host's immune system. This review focuses on the microbiological, clinical, immunological, and biochemical aspects of the pathogenesis of H. pylori .

Pathogenesis of Helicobacter pylori Infection

SUMMARY

Helicobacter pylori is the first formally recognized bacterial carcinogen and is one of the most successful human pathogens, as over half of the world's population is colonized with this gram-negative bacterium. Unless treated, colonization usually persists lifelong. H. pylori infection represents a key factor in the etiology of various gastrointestinal diseases, ranging from chronic active gastritis without clinical symptoms to peptic ulceration, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Disease outcome is the result of the complex interplay between the host and the bacterium. Host immune gene polymorphisms and gastric acid secretion largely determine the bacterium's ability to colonize a specific gastric niche. Bacterial virulence factors such as the cytotoxin-associated gene pathogenicity island-encoded protein CagA and the vacuolating cytotoxin VacA aid in this colonization of the gastric mucosa and subsequently seem to modulate the host's immune system. This review focuses on the microbiological, clinical, immunological, and biochemical aspects of the pathogenesis of H. pylori .

Pathogenesis of Helicobacter pylori Infection

SUMMARY

Helicobacter pylori is the first formally recognized bacterial carcinogen and is one of the most successful human pathogens, as over half of the world's population is colonized with this gram-negative bacterium. Unless treated, colonization usually persists lifelong. H. pylori infection represents a key factor in the etiology of various gastrointestinal diseases, ranging from chronic active gastritis without clinical symptoms to peptic ulceration, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Disease outcome is the result of the complex interplay between the host and the bacterium. Host immune gene polymorphisms and gastric acid secretion largely determine the bacterium's ability to colonize a specific gastric niche. Bacterial virulence factors such as the cytotoxin-associated gene pathogenicity island-encoded protein CagA and the vacuolating cytotoxin VacA aid in this colonization of the gastric mucosa and subsequently seem to modulate the host's immune system. This review focuses on the microbiological, clinical, immunological, and biochemical aspects of the pathogenesis of H. pylori .

Pathogenesis of Helicobacter pylori infection

Helicobacter pylori is the first formally recognized bacterial carcinogen and is one of the most successful human pathogens, as over half of the world's population is colonized with this gram-negative bacterium. Unless treated, colonization usually persists lifelong. H. pylori infection represents a key factor in the etiology of various gastrointestinal diseases, ranging from chronic active gastritis without clinical symptoms to peptic ulceration, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Disease outcome is the result of the complex interplay between the host and the bacterium. Host immune gene polymorphisms and gastric acid secretion largely determine the bacterium's ability to colonize a specific gastric niche. Bacterial virulence factors such as the cytotoxin-associated gene pathogenicity island-encoded protein CagA and the vacuolating cytotoxin VacA aid in this colonization of the gastric mucosa and subsequently seem to modulate the host's immune system. This review focuses on the microbiological, clinical, immunological, and biochemical aspects of the pathogenesis of H. pylori.

Development potential of rifalazil and other benzoxazinorifamycins

Rifalazil and other benzoxazinorifamycins (new chemical entities [NCEs]) are rifamycins that contain a distinct planar benzoxazine ring. Rifalazil has excellent antibacterial activity, high intracellular levels and high tissue penetration, which are attributes that favour its use in treating diseases caused by the obligate intracellular pathogens of the genus Chlamydia. Recent studies have shown that rifalazil has efficacy in the treatment of human sexually transmitted disease caused by Chlamydia trachomatis. The extraordinary potency of rifalazil and other NCEs, such as ABI-0043, extends to the related microorganism, C. pneumoniae, a respiratory pathogen that can disseminate and persist chronically in the vasculature, resulting in increased plaque formation in animal studies. A pivotal clinical trial with rifalazil has been initiated for the treatment of peripheral arterial disease. Other opportunities include gastric ulcer disease caused by Helicobacter pylori and antibiotic-associated colitis caused by infection with Clostridium difficile in the colon. The NCEs could prove to be valuable as follow-on compounds in these indications, as rifampin replacements in antibacterial combination therapy or as stand-alone topical antibacterials (e.g., to treat acne). Neither rifalazil nor NCEs appear to induce the cytochrome P450 3A4, an attribute of rifampin that can result in adverse events due to drug-drug interactions.