Treatment of Helicobacter pylori infection

Helicobacter pylori among patients with symptoms of gastroduodenal ulcer disease in rural Uganda

Introduction

To meet key millennium development goals, the rural population needs to be reached for health assessment and service delivery. Gastroduodenal ulcer disease is a common ailment affecting the health of people in Uganda. A cross-sectional study was conducted at Bwera Hospital in Kasese district of western Uganda, to establish the prevalence and predisposing factors of Helicobacter pylori among gastroduodenal ulcer disease patients.

Methods

A sample of 174 patients with symptoms of gastroduodenal ulcer disease was purposively obtained. Using two laboratory test methods, the prevalence of H. pylori among these patients was determined. A structured questionnaire was administered to participants to establish their demographic background and selected aspects of their lifestyle. Finally, the results obtained by enzyme-linked immunosorbent assay (ELISA) and immunochromatographic rapid test (IRT) were compared.

Results

We established the prevalence of H. pylori as 29.9% (52/174) by ELISA and 37.4% (65/174) by IRT. Cigarette smoking, poor sanitation, and lack of formal education were the significant predisposing factors with p-values <0.05. The two tests gave identical results in 87.9% of the patients.

Discussion

The prevalence of H. pylori by IRT and ELISA test methods was similar to what has been reported elsewhere in developed countries; but was lower than previously reported in developing countries including Uganda. The previous studies in Uganda were carried out in the urban population and on young children; and some used antibody-detection methods only, therefore leading to different prevalence as a result of difference in study population and methods.

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.

Gastroretentive drug delivery systems for the treatment of Helicobacter pylori

Helicobacter pylori (H. pylori) is one of the most common pathogenic bacterial infections and is found in the stomachs of approximately half of the world's population. It is the primary known cause of gastritis, gastroduodenal ulcer disease and gastric cancer. However, combined drug therapy as the general treatment in the clinic, the rise of antibiotic-resistant bacteria, adverse reactions and poor patient compliance are major obstacles to the eradication of H. pylori. Oral site-specific drug delivery systems that could increase the longevity of the treatment agent at the target site might improve the therapeutic effect and avoid side effects. Gastroretentive drug delivery systems potentially prolong the gastric retention time and controlled/sustained release of a drug, thereby increasing the concentration of the drug at the application site, potentially improving its bioavailability and reducing the necessary dosage. Recommended gastroretentive drug delivery systems for enhancing local drug delivery include floating systems, bioadhesive systems and expandable systems. In this review, we summarize the important physiological parameters of the gastrointestinal tract that affect the gastric residence time. We then focus on various aspects useful in the development of gastroretentive drug delivery systems, including current trends and the progress of novel forms, especially with respect to their application for the treatment of H. pylori infections.

Is levofloxacin-based triple therapy an alternative for first-line eradication of Helicobacter pylori? A systematic review and meta-analysis

OBJECTIVES

To evaluate the available data on the efficacy and safety of levofloxacin-based triple therapy compared with standard triple therapy in first-line treatment for Helicobacter pylori infection.

METHODS

By searching MEDLINE, The Cochrane Central Register of Controlled Trials, and Web of Knowledge, two independent reviewers systemically identified randomized controlled trials comparing levofloxacin-based triple regimen with standard triple therapy for first-line treatment of H. pylori infection. The pooled risk ratios (RR) and 95% confidence intervals were calculated.

RESULTS

Overall, nine randomized controlled trials including 1275 patients have been treated with levofloxacin-based triple therapy and 1237 patients with standard regimen. Eradication rate in the levofloxacin-based therapy group was slightly higher than that in the standard triple therapy group regardless of treatment duration (80.2% vs. 77.4%, RR=1.03, 95% CI=0.94-1.13). Subgroup analysis related to different geographic areas found that efficacy of 7-day standard triple regimen was statistically superior to 7-day levofloxacin-based scheme in Asian group (RR=0.91, 95% CI=0.86-0.97), but levofloxacin-based triple therapy was predominant regardless of treatment time in European countries (RR=1.15, 95% CI=1.06-1.23). There was no significant difference between two groups in the incidence of overall adverse events or in the occurrence of discontinuing therapy due to side effects.

CONCLUSIONS

The 10-day levofloxacin-based triple therapy may be considered as an alternative for increasing cure rate of H. pylori infection in European areas. But in Asian countries, standard triple regimen is still superior to levofloxacin-based therapy as first-line regimen for H. pylori eradication.

Anti-inflammatory properties of gastric-derived Lactobacillus plantarum XB7 in the context of Helicobacter pylori infection

BACKGROUND

Helicobacter pylori colonization of the gastric epithelium induces interleukin-8 (IL-8) production and inflammation leading to host cell damage. We searched for gastric-derived Lactobacillus with the ability to suppress H. pylori-induced inflammation.

MATERIALS AND METHODS

Conditioned media from gastric-derived Lactobacillus spp. were tested for the ability to suppress H. pylori-induced IL-8 production in AGS gastric epithelial cells. IL-8 protein and mRNA levels were measured by ELISA and qPCR, respectively. The changes on host cell signaling pathway were analyzed by Western blotting and the anti-inflammatory effect was tested in a Sprague-Dawley rat model.

RESULTS

Conditioned media from L. salivarius B101, L. rhamnosus B103, and L. plantarum XB7 suppressed IL-8 production and IL-8 mRNA expression in H. pylori-induced AGS cells without inhibiting H. pylori growth. Conditioned media from LS-B101, LR-B103, and LP-XB7 suppressed the activation of NF-κB in AGS cells, while strain LP-XB7 also suppressed c-Jun activation. The anti-inflammatory effect of LP-XB7 was further assessed in vivo using a H. pylori-infected Sprague-Dawley rat model. Strain LP-XB7 contributed to a delay in the detection and colonization of H. pylori in rat stomachs, attenuated gastric inflammation, and ameliorated gastric histopathology. Additionally, the administration of LP-XB7 correlated with the suppression of TNF-α and CINC-1 in sera, and suppression of CINC-1 in the gastric mucosa of H. pylori-infected rats.

CONCLUSIONS

These results suggest that L. plantarum XB7 produces secreted factors capable of modulating inflammation during H. pylori infection, and this probiotic Lactobacillus strain shows promise as an adjunctive therapy for treating H. pylori-associated disease.

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.

Helicobacter pylori eradication: are we really all equal? A controlled study in native and immigrant population

Italy's shift to a tertiary economy has modified the working market, concentrating demand also on unqualified one, which includes most immigrants. It is also well established that low socio-economical conditions are associated with an increased prevalence of H. pylori infection. The aims of this study were to compare: (1) the efficacy of a 7 days triple therapy in immigrant and in Italian patients; (2) the prevalence of PUD between these two groups of patients. A total of 116 consecutive immigrant and 112 Italian H. pylori infected patients were recruited between 2007 and 2008. Patients underwent (13)C-UBT, endoscopy with biopsies, and were offered a 7-day triple therapy. Eradication rate (ER) was assessed 8 weeks after the end of the treatment using (13)C-UBT. The two populations differed for median age (p < 0.01), prevalence of PUD (p < 0.01), and smoking status (p < 0.01). The ER according to the ITT analysis was 70% for Italian and 48.3% for immigrant (p < 0.01). Multivariate analysis including country of origin, sex, age, PUD, smoking, and alcohol status found that immigrant had an adjusted OR for not eradicating of 2.14 (p = 0.03). In immigrant patients resident in Italy, performance of triple therapy was lower than expected. Further studies are demanded to confirm and clarify these intriguing results.

Antimicrobial susceptibility of Helicobacter pylori strains isolated from patients in Shiraz, Southern Iran

AIM: To improve our understanding of Iranian regional variation in Helicobacter pylori (H. pylori) antibiotic resistance rates to find the best antibiotic therapy for eradication of H. pylori infections.

METHODS: A total of 266 patients undergoing endoscopy in Shiraz, Southern Iran, were included in this study. H. pylori strains were isolated from antral biopsies by culture and confirmed by the rapid urease-test and gram staining. Antibiotic susceptibility of H. pylori isolates was determined by E-test.

RESULTS: A total of 121 H. pylori strains were isolated, 50 from male and 71 from female patients. Data showed that 44% (n = 53), 20% (n = 24), 5% (n = 6), and 3% (n = 4) of all strains were resistant to the antibiotics metronidazole, amoxicillin, clarithromycin, and tetracycline, respectively. When the antibiotics were considered together we found 11 sensitivity patterns for the strains. Resistance to metronidazole was significantly higher in female than in male patients (P < 0.05). In about 71% of the metronidazole-resistant isolates, the minimum inhibitory concentrations (MICs) exceeded 256 μg/mL.

CONCLUSION: We found a moderate rate of primary resistance to metronidazole. However, a high MIC (> 256 mg/L) which was found in 71% of the isolates is considerable. In the case of amoxicillin, an increased resistance rate of 20% is worrying. Resistance to clarithromycin and tetracycline is also emerging among the H. pylori strains in our region.

Efficacy and safety of Levofloxacin, Clarithromycin and Esomeprazol as first line triple therapy for Helicobacter pylori eradication in Middle East. Prospective, randomized, blind, comparative, multicenter study

BACKGROUND/AIMS

Antibiotic resistance and poor compliance are the main causes of Helicobacter pylori (H. pylori ) eradication failure. This study evaluated the eradication rate, tolerability, and compliance of Levofloxacin, Clarithromycin and Esomeprazol combined triple therapy for H. pylori eradication.

PATIENTS AND METHODS

Four hundred-fifty patients from 3 centres who were diagnosed to have Helicobacter pylori infection by (13)C-urea breath test were randomized into 3 equal groups; group 1 (CAE) received Clarithromycin 500mg twice daily, Amoxicillin 1000mg twice daily, plus Esomeprazol 20mg twice daily for 7 days, group 2 (LAE) received Levofloxacin 500mg once daily, Amoxicillin 1000mg twice daily, plus Esomeprazol 20mg twice daily for 7 days, group 3 (CLE) received Levofloxacin 500mg once daily, Clarithromycin 500mg twice daily, plus Esomeprazol 20mg twice daily for 7 days. 436 patients were re-evaluated by (13)C-urea breath test after 6weeks from completion of treatment.

RESULTS

H. pylori eradication (intention to treat) was successful in 136/150 (90.6%) with CLE, 127/150 (84.7%) with LAE and 118/150 (78.6%) with CAE. There was a significant difference (p<0.001) regarding treatment success between CLE and LAE when compared with CAE. There was no difference among the treatment groups with regard to the incidence and severity of adverse events reported.

CONCLUSION

The combined Levofloxacin, and Clarithromycin and Esomeprazol based regimen as first line triple therapy for H. pylori eradication can give more significant eradication rate with same safety when compared with classic triple therapy.

Novel Helicobacter pylori therapeutic targets: the unusual suspects

Understanding the current status of the discovery and development of anti-Helicobacter therapies requires an overview of the searches for therapeutic targets performed to date. A summary is given of the very substantial body of work conducted in the quest to find Helicobacter pylori genes that could be suitable candidates for therapeutic intervention. The products of most of these genes perform metabolic functions, and others have roles in growth, cell motility and colonization. The genes identified as potential targets have been organized into three categories according to their degree of characterization. A short description and evaluation is provided of the main candidates in each category. Investigations of potential therapeutic targets have generated a wealth of information about the physiology and genetics of H. pylori, and its interactions with the host, but have yielded little by way of new therapies.

Characterization of clarithromycin resistance in Malaysian isolates of Helicobacter pylori

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

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

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

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

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.

Effect of specific colostral antibodies and selected lactobacilli on the adhesion of Helicobacter pylori on AGS cells and the Helicobacter-induced IL-8 production

Helicobacter pylori infection is the most common cause of gastritis, gastric ulcer and adenocarcinoma. It has proven difficult to cure because of its capability to develop strains resistant to antibiotics. The effect of three strains of lactic acid bacteria (LAB) and bovine colostral preparations on the adhesion of H. pylori NCTC 11637 on gastric adenocarcinoma (AGS) cells and on the interleukin (IL)-8 production was studied. Before infection, H. pylori were pretreated with Lactobacillus plantarum MLBPL1, Lactobacillus rhamnosus GG, Lactococcus lactis, or with a colostral preparation with or without specific H. pylori antibodies. The relative number of H. pylori adhered on AGS cells was determined by urease test. IL-8 produced by the cells was studied by enzyme-linked immunosorbent assay. Colostral preparations with and without specific antibodies reduced the adhesion of H. pylori on AGS cells in a dose-dependent manner. Live LAB at a concentration of 10(10) CFU/ml reduced the adhesion by approximately 50% (P < 0.05). After the infection of AGS cells by H. pylori, the IL-8 level rose up to about 10-fold (5500 +/- 1600 pg/ml). Pretreatment of H. pylori with colostral preparations or high concentrations of LAB prevented this IL-8 rise. Similar effect was seen with live and heat-killed LAB, the live LAB being more effective. Heat-killed LAB at a concentration of 10(10) CFU/ml rose the IL-8 level of non-infected cells significantly. Suppression of IL-8 production by LAB or colostral products could have a suppressive effect on inflammation in Helicobacter infection.

Inhibition of Helicobacter pylori-induced inflammation in human gastric epithelial AGS cells by Phyllanthus urinaria extracts

AIM OF THE STUDY

Helicobacter pylori is linked to a majority of peptic ulcers and to some types of gastric cancer, and its resistance to antibiotic treatment is now found worldwide. This study is aimed at evaluating the antimicrobial activity of Phyllanthus urinaria Linnea (Euphorbiaceae), chloroform (PUC) and methanol (PUM) extracts, and its eight isolates on H. pylori-infected human gastric epithelial AGS cells.

MATERIALS AND METHODS

The in vitro anti-bacterial activity of P. urinaria chloroform (PUC) and methanol (PUM) extracts, and its eight isolates were determined. Additional experiments were also performed to know the PUC and PUM ability to inhibit the H. pylori adhesion to and invasion of AGS cells, in addition to the effect of PUC on NF-kappaB activity as well as IL-8 synthesis during H. pylori infection of AGS cells.

RESULTS

The results revealed that crude extracts PUC and PUM showed potent antimicrobial activity against H. pylori than pure isolates. On the other hand, in vitroH. pylori-infection model revealed that the inhibition of bacterial adhesion and invasion to AGS cells has dramatically reduced by treatment of extract PUC, while PUM has the same moderate effect. Furthermore, H. pylori-induced nuclear factor (NF)-kappaB activation, and the subsequent release of interleukin (IL)-8 in AGS cells were also inhibited by the extract PUC.

CONCLUSIONS

These results open the possibility of considering P. urinaria a chemopreventive agent for peptic ulcer or gastric cancer, but this bioactivity should be confirmed in vivo in the future.

Effect of the CYP2C19 polymorphism on the eradication rate of Helicobacter pylori infection by 7-day triple therapy with regular proton pump inhibitor dosage

BACKGROUND AND AIM

Proton pump inhibitors (PPI) are mainly metabolized by cytochrome P450 2C19 (CYP2C19) in the liver. We investigated whether the CYP2C19 genotype plays a role in the eradication rate of Helicobacter pylori (H. pylori) infection in patients receiving pantoprazole- or esomeprazole-based triple therapy.

METHODS

A total of 327 patients infected with H. pylori were treated with either pantoprazole or esomeprazole, plus amoxicillin and clarithromycin for 7 days. The presence of the CYP2C19 genotype was determined by pyrosequencing.

RESULTS

The overall H. pylori eradication rate was 85%; 82.6% for the PAC regimen, and 88.3% for the EAC regimen; the differences were not statistically significant. The overall eradication rate in the poor metabolizer groups (PM) was significantly higher than in the extensive metabolizer groups (EM) (97.4% vs 83.3%; P = 0.016). The eradication rates in the EM and PM groups were 80.8% and 95.7% for the PAC regimen and 86.8% and 100% for the EAC regimen, respectively.

CONCLUSION

The results of this study suggest that the CYP2C19 genotype status may play a role in the H. pylori eradication rate in patients receiving pantoprazole or esomeprazole-based triple therapy.

Expression, purification, crystallization and preliminary X-ray analysis of an NAD-dependent glyceraldehyde-3-phosphate dehydrogenase from Helicobacter pylori

Helicobacter pylori is a dangerous human pathogen that resides in the upper gastrointestinal tract. Little is known about its metabolism and with the onset of antibiotic resistance new treatments are required. In this study, the expression, purification, crystallization and preliminary X-ray diffraction of an NAD-dependent glyceraldehyde-3-phosphate dehydrogenase from H. pylori are reported.

Helicobacter pylori infection in children: management and pharmacotherapy

Helicobacter pylori infection is mainly acquired during childhood: it is recognised as a cause of gastritis and peptic ulcer and it has been classified as a group A carcinogen by the World Health Organisation. The exact mode of transmission is as yet unknown. The aim of this review was to analyse the literature about H. pylori infection in paediatric patients. The large diffusion of H. pylori infection in paediatric patients, the absence of a specific clinical feature, the new non-invasive methods for diagnosis and follow-up, which are still not validated and the different therapeutic schedules have led to the necessity of determining the real clinical outcome in affected children and adolescents. The scope of the review was to identify better eradication therapy and the most important factors in treatment failure. The international literature has shown the importance of culture, antibiograms, the compliance of families and patients and the use of probiotics during triple eradication therapy. The review paid attention to the management, diagnostic techniques and therapy of this infection in paediatric patients.

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

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

An alternative salvage regimen for Helicobacter pylori-resistant patients with heart failure

Helicobacter pylori infects over 50% of the worldwide population. For eradication, European, Canadian, and American guidelines recommend a regimen consisting of a proton pump inhibitor, clarithromycin, and metronidazole or amoxicillin dosed twice daily for at least 7 days. When this treatment strategy fails, a complex, multidosed bismuth-based quadruple regimen is recommended. Unfortunately, for patients with heart failure, this salvage regimen can be potentially hazardous due to the drug-drug interaction with tetracycline and digoxin, as well as the large salicylate content with bismuth subsalicylate. As H. pylori infection is so prevalent, providers will most likely encounter such a therapeutic dilemma. A safe, effective, and simplistic alternative is a 10-day fluoroquinolone-based regimen consisting of a proton pump inhibitor, levofloxacin and either clarithromycin or amoxicillin. Levofloxacin demonstrates excellent bioavailability, widespread tissue and fluid distribution, extended half-life, limited drug interaction profile, low incidence of side effects, and remarkable activity against H. pylori with minimal primary resistance. Compared to the 7-day quadruple regimen, a 10-day levofloxacin-based regimen demonstrated a greater eradication rate, better tolerability, and a lower rate of therapy discontinuation. We briefly provide a summary of the data regarding this levofloxacin-based regimen and two successful cases from our heart failure clinic.

Effect of MDR1 C3435T polymorphism on cure rates of Helicobacter pylori infection by triple therapy with lansoprazole, amoxicillin and clarithromycin in relation to CYP 2C19 genotypes and 23S rRNA genotypes of H. pylori

BACKGROUND

Polymorphism in MDR1 is associated with variation in the plasma level of a proton pump inhibitor.

AIM

To investigate whether MDR1 polymorphism is associated with eradication rates of Helicobacter pylori by a triple therapy with lansoprazole, amoxicillin and clarithromycin in relation to CYP2C19 genotype status and bacterial susceptibility to clarithromycin.

METHODS

A total of 313 patients infected with H. pylori completed the treatment with lansoprazole 30 mg b.d., clarithromycin 200 mg b.d. and amoxicillin 750 mg b.d. for 1 week. MDR1 C3435T polymorphism and CYP2C19 genotypes of patients and sensitivity of H. pylori to clarithromycin were determined.

RESULTS

Logistic regression analysis revealed that the MDR1 polymorphism as well as CYP2C19 genotypes of patients and clarithromycin-resistance of H. pylori were significantly associated with successful eradication. Eradication rates for H. pylori were 82% (83/101: 95% CI = 73-89), 81% (112/139: CI = 73-87), and 67% (44/73: CI = 48-72) in patients with the MDR1 3435 C/C, C/T and T/T genotype, respectively (P = 0.001).

CONCLUSIONS

Polymorphism of MDR1 is one of the determinants of successful eradication of H. pylori by the triple therapy with lansoprazole, amoxicillin and clarithromycin, together with CYP2C19 genotype and bacterial susceptibility to clarithromycin.

Personalized medicine for eradication of Helicobacter pylori

Regimens for eradication of Helicobacter pylori consist of a proton-pump inhibitor (PPI) and one or two antimicrobial agents, such as amoxicillin, clarithromycin or metronidazole. As the pharmacokinetics and pharmacodynamics of PPIs are affected by polymorphism of CYP2C19, doses and dosing schemes of a PPI should be optimized based on genotype status of each patient in order to yield higher eradication rates. PPIs affect the pharmacokinetics of other substrates of CYP2C19, such as warfarin and diazepam. Acid inhibition induced by a PPI also affects the pharmacokinetics of some drugs, such as itraconazole. Clarithromycin, one of the most frequently used antimicrobial agents in eradication of H. pylori, inhibits activity of CYP3A4, meaning that the pharmacokinetics of substrates of CYP3A4 are affected by clarithromycin. Therefore, clinicians must pay attention to the other drugs dosed to each of their patients. Therefore, the eradication regimen for H. pylori infection should be designed with the CYP2C19 genotype status, bacterial susceptibility to antimicrobial agents, and other drugs being taken by each patient having been taken into consideration.

In vitro activity of olive oil polyphenols against Helicobacter pylori

Helicobacter pylori is linked to a majority of peptic ulcers and to some types of gastric cancer, and resistance of the microorganism to antibiotic treatment is now found worldwide. Virgin olive oil is an unrefined vegetable oil that contains a significant amount of phenolic compounds. Under simulated conditions, we have demonstrated that these substances can diffuse from the oil into the gastric juice and be stable for hours in this acidic environment. In vitro, they exerted a strong bactericidal activity against eight strains of H. pylori, three of them resistant to some antibiotics. Among the phenolic compounds, the dialdehydic form of decarboxymethyl ligstroside aglycon showed the strongest bactericidal effect at a concentration as low as 1.3 microg/mL. Although the experimental conditions are different from other reported works, this bactericidal concentration is much lower than those found for phenolic compounds from tea, wine, and plant extracts. These results open the possibility of considering virgin olive oil a chemopreventive agent for peptic ulcer or gastric cancer, but this bioactivity should be confirmed in vivo in the future.