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Metronidazole Resistance (metronidazole + resistance)
Selected AbstractsAlaska Sentinel Surveillance for Antimicrobial Resistance in Helicobacter pylori Isolates from Alaska Native Persons, 1999,2003HELICOBACTER, Issue 6 2006Michael G. Bruce Abstract Background:, Previous studies in Alaska have demonstrated elevated proportions of antimicrobial resistance among Helicobacter pylori isolates. Materials and Methods:, We analyzed H. pylori data from the Centers for Disease Control and Prevention (CDC)'s sentinel surveillance in Alaska from July 1999 to June 2003 to determine the proportion of culture-positive biopsies from Alaska Native persons undergoing routine upper-endoscopy, and the susceptibility of H. pylori isolates to metronidazole [minimum inhibitory concentration (MIC) of > 8 g metronidazole/mL), clarithromycin (MIC , 1), tetracycline (MIC , 2) and amoxicillin (MIC , 1)] using agar dilution. Results:, Nine-hundred sixty-four biopsy specimens were obtained from 687 participants; 352 (51%) patients tested culture positive. Mean age of both culture-positive and culture-negative patients was 51 years. Metronidazole resistance was demonstrated in isolates from 155 (44%) persons, clarithromycin resistance from 108 (31%) persons, amoxicillin resistance from 8 (2%) persons, and 0 for tetracycline resistance. Metronidazole and clarithromycin resistance varied by geographic region. Female patients were more likely than male subjects to show metronidazole resistance (p < .01) and clarithromycin resistance (p = .05). Conclusions:, Resistance to metronidazole and clarithromycin is more common among H. pylori isolates from Alaska Native persons when compared with those from elsewhere in the USA. [source] The HOMER Study: The Effect of Increasing the Dose of Metronidazole When Given with Omeprazole and Amoxicillin to Cure Helicobacter pylori InfectionHELICOBACTER, Issue 4 2000Karna Dev Bardhan Background.Helicobacter pylori eradication with omeprazole, amoxycillin, and metronidazole is both effective and inexpensive. However, eradication rates with different dosages and dosing vary, and data on the impact of resistance are sparse. In this study, three different dosages of omeprazole, amoxycillin, and metronidazole were compared, and the influence of metronidazole resistance on eradication was assessed. Methods. Patients (n = 394) with a positive H. pylori screening test result and endoscopy-proven duodenal ulcer in the past were enrolled into a multicenter study performed in four European countries and Canada. After baseline endoscopy, patients were randomly assigned to treatment for 1 week with either omeprazole, 20 mg twice daily, plus amoxycillin, 1,000 mg twice daily, plus metronidazole, 400 mg twice daily (low M); or omeprazole, 40 mg once daily, plus amoxycillin, 500 mg three times daily, plus metronidazole, 400 mg three times daily (medium M); or omeprazole, 20 mg twice daily, plus amoxycillin, 1,000 mg twice daily, plus metronidazole, 800 mg twice daily (high M). H. pylori status at entry was assessed by a 13C urea breath test and a culture. Eradication was defined as two negative 13C-urea breath test results 4 and 8 weeks after therapy. Susceptibility testing using the agar dilution method was performed at entry and in patients with persistent infection after therapy. Results. The eradication rates, in terms of intention to treat (ITT) (population n = 379) (and 95% confidence interval [CI]) were as follows: low M 76% (68%, 84%), medium M 76% (68%, 84%), and high M 83% (75%, 89%). By per-protocol analysis (population n = 348), the corresponding eradication rates were: low M 81%, medium M 80%, and high M 85%. No H. pylori strains were found to be resistant to amoxycillin. Prestudy resistance of H. pylori strains to metronidazole was found in 72 of 348 (21%) of the cultures at entry (range, 10%,39% in the five countries). The overall eradication rate in prestudy metronidazole-susceptible strains was 232 of 266 (87%) and, for resistant strains, it was 41 of 70 (57%; p < .001). Within each group, the results were as follows (susceptible/resistant): low M, 85%/54%; medium M, 86%/50%; and high M, 90%/75%. There were no statistically significant differences among the treatment groups. 23 strains susceptible to metronidazole before treatment were recultured after therapy failed; 20 of these had now developed resistance. Conclusions.H. pylori eradication rates were similar (approximately 80%) with all three regimens. Metronidazole resistance reduced efficacy; increasing the dose of metronidazole appeared not to overcome the problem or significantly improve the outcome. Treatment failure was generally associated with either prestudy or acquired metronidazole resistance. These findings are of importance when attempting H. pylori eradication in communities with high levels of metronidazole resistance. [source] Geographical difference in antimicrobial resistance pattern of Helicobacter pylori clinical isolates from Indian patients: Multicentric studyJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2003SP THYAGARAJAN Abstract Aim:, To assess the pattern of antimicrobial resistance of Helicobacter pylori isolates from peptic ulcer disease patients of Chandigarh, Delhi, Lucknow, Hyderabad and Chennai in India, and to recommend an updated anti- H. pylori treatment regimen to be used in these areas. Methods:, Two hundred and fifty-nine H. pylori isolates from patients with peptic ulcer disease reporting for clinical management to the Post Graduate Institute of Medical Education and Research, Chandigarh; All India Institute of Medical Sciences, New Delhi; Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow; Deccan College of Medical Sciences and Allied Hospitals, Hyderabad; and hospitals in Chennai in collaboration with the Dr ALM Post Graduate Institute of Basic Medical Sciences were analyzed for their levels of antibiotic susceptibility to metronidazole, clarithromycin, amoxycillin, ciprofloxacin and tetracycline. The Epsilometer test (E-test), a quantitative disc diffusion antibiotic susceptibility testing method, was adopted in all the centers. The pattern of single and multiple resistance at the respective centers and at the national level were analyzed. Results:, Overall H. pylori resistance rate was 77.9% to metronidazole, 44.7% to clarithromycin and 32.8% to amoxycillin. Multiple resistance was seen in 112/259 isolates (43.2%) and these were two/three and four drug resistance pattern to metronidazole, clarithromycin, amoxycillin observed (13.2, 32 and 2.56%, respectively). Metronidazole resistance was high in Lucknow, Chennai and Hyderabad (68, 88.2 and 100%, respectively) and moderate in Delhi (37.5%) and Chandigarh (38.2%). Ciprofloxacin and tetracycline resistance was the least, ranging from 1.0 to 4%. Conclusion:, In the Indian population, the prevalence of resistance of H. pylori is very high to metronidazole, moderate to clarithromycin and amoxycillin and low to ciprofloxacin and tetracycline. The rate of resistance was higher in southern India than in northern India. The E-test emerges as a reliable quantitative antibiotic susceptibility test. A change in antibiotic policy to provide scope for rotation of antibiotics in the treatment of H. pylori in India is a public health emergency. [source] Analysis of drug resistance and virulence-factor genotype of Irish Helicobacter pylori strains: is there any relationship between resistance to metronidazole and cagA status?ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 7 2009I. TANEIKE Summary Background,Helicobacter pylori infection is eradicated with antimicrobial agents and drug-resistant strains make successful treatment difficult. Geographical variations in virulence-factor genotype also exist. Aim, To evaluate prevalence of drug resistance and virulence-factor genotype in Irish H. pylori strains and to investigate if there is any relationship between drug resistance and genotype. Methods,Helicobacter pylori strains isolated from 103 patients were examined. Antimicrobial susceptibilities were tested by Etest. The virulence-factor genotypes were determined using PCR. Frequencies of spontaneous metronidazole-resistance were measured in vitro. Results, Metronidazole resistance was present in 37.9% of strains examined. 16.5% of strains were clarithromycin-resistant and resistance to both agents observed was found in 12.6% of strains. 68% of strains were cagA+. The dominant vacA type was s1/m2, followed by s1/m1 and s2/m2. The metronidazole resistance rate in cagA, group was significantly higher than in cagA+ (P = 0.0089). Spontaneous resistance to metronidazole in cagA, occurred in higher frequency when compared with cagA+. Conclusions,cagA+ and vacAs1/m2 type was the dominant genotype in Irish H. pylori strains. Significant rates of metronidazole resistance were observed in cagA, group. cagA, strains tend to acquire metronidazole resistance in vitro. Absence of cagA might be a risk factor in development of metronidazole resistance. [source] High prevalence and level of resistance to metronidazole, but lack of resistance to other antimicrobials in Helicobacter pylori, isolated from a multiracial population in KuwaitALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2006M. JOHN ALBERT Summary Background The primary treatment regimen for Helicobacter pylori infection for Kuwaitis does not contain metronidazole, but that for expatriates does. There is also increasing failure of antimicrobial therapy. Aim To determine the susceptibility of H. pylori from upper gastrointestinal biopsies of Kuwaitis and non-Kuwaitis to find out if differences existed in the susceptibilities of the isolates from the two different populations. Methods The susceptibilities of 96 H. pylori isolates were tested against metronidazole, amoxicillin, clarithromycin and tetracycline by the E test. The rdxA gene was analysed from selected metronidazole-susceptible and metronidazole-resistant strains to find out polymorphism and the basis of metronidazole resistance. Results Approximately, 70% of isolates from both populations were metronidazole resistant with 65% isolates showing high minimum inhibitory concentration values of >256 ,g/mL. No resistance to the other three antimicrobials was found. There were novel nonsense and missense mutations with no deletion in the rdxA gene by insertion of mini-IS605. Conclusions The prevalence and level of metronidazole resistance in H. pylori in the two populations was high with no difference, in spite of different treatment regimens. Metronidazole resistance in this transitional country appeared to be independent of prior metronidazole use for treatment of H. pylori infection. [source] Helicobacter pylori antimicrobial resistance in the United Kingdom: the effect of age, sex and socio-economic statusALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2001H. K. Parsons Background: Helicobacter pylori antimicrobial resistance is the most common reason for eradication failure. Small studies have shown metronidazole resistance to be more prevalent in certain population groups. Aim: To determine the resistance rates in a large cohort of patients from a single centre in the UK, and to evaluate resistance patterns over time, according to age, sex and socio-economic status. Methods: Consecutive patients with H. pylori -positive antral gastric biopsy samples were studied from 1994 to 1999. Susceptibility testing was performed to metronidazole, tetracycline, macrolide and amoxicillin by the modified disk diffusion method. The Jarman under-privileged area score was used as a measure of socio-economic status. Results: A total of 1064 patients were studied. Overall metronidazole resistance was 40.3%, decreasing with age (P < 0.0001, odds ratio for patients over 60 years 0.63, 95% CI: 0.48,0.80). Women were more likely to have metronidazole resistant strains (P=0.003, odds ratio 1.5, 95% CI: 1.15,1.91), but there was no association with Jarman score. Macrolide resistance was associated with metronidazole resistance (P=0.03, odds ratio 2.14, 95% CI: 1.07,4.28). Conclusions: Metronidazole resistance in H. pylori is highly prevalent and more common in women and the young, but does not appear to be related to socio-economic status. [source] Alaska Sentinel Surveillance for Antimicrobial Resistance in Helicobacter pylori Isolates from Alaska Native Persons, 1999,2003HELICOBACTER, Issue 6 2006Michael G. Bruce Abstract Background:, Previous studies in Alaska have demonstrated elevated proportions of antimicrobial resistance among Helicobacter pylori isolates. Materials and Methods:, We analyzed H. pylori data from the Centers for Disease Control and Prevention (CDC)'s sentinel surveillance in Alaska from July 1999 to June 2003 to determine the proportion of culture-positive biopsies from Alaska Native persons undergoing routine upper-endoscopy, and the susceptibility of H. pylori isolates to metronidazole [minimum inhibitory concentration (MIC) of > 8 g metronidazole/mL), clarithromycin (MIC , 1), tetracycline (MIC , 2) and amoxicillin (MIC , 1)] using agar dilution. Results:, Nine-hundred sixty-four biopsy specimens were obtained from 687 participants; 352 (51%) patients tested culture positive. Mean age of both culture-positive and culture-negative patients was 51 years. Metronidazole resistance was demonstrated in isolates from 155 (44%) persons, clarithromycin resistance from 108 (31%) persons, amoxicillin resistance from 8 (2%) persons, and 0 for tetracycline resistance. Metronidazole and clarithromycin resistance varied by geographic region. Female patients were more likely than male subjects to show metronidazole resistance (p < .01) and clarithromycin resistance (p = .05). Conclusions:, Resistance to metronidazole and clarithromycin is more common among H. pylori isolates from Alaska Native persons when compared with those from elsewhere in the USA. [source] Impact of Furazolidone-Based Quadruple Therapy for Eradication of Helicobacter pylori after Previous Treatment FailuresHELICOBACTER, Issue 4 2002G. Treiber Abstract Background. One week of quadruple therapy including metronidazole is recommended for Helicobacter pylori treatment failures after first line therapy regardless of resistance status. This study investigated whether a quadruple regimen containing furazolidone could be effective as a third-line (salvage) therapy. Methods. All patients with previous H. pylori treatment failure after a clarithromycin-metronidazole ± amoxicillin combination plus acid suppression were given lansoprazole 30 mg twice a day (bid), tripotassiumdicitratobismuthate 240 mg bid, tetracycline 1 g bid, metronidazole 400 mg (PPI-B-T-M) three times a day (tid) for 1 week. In the case of treatment failure with this second-line therapy, the same regimen was applied for 1 week except for using furazolidone 200 mg bid (PPI-B-T-F) instead of metronidazole (sequential study design). Results. Eighteen consecutive patients were treated with PPI-B-T-M. Eleven of those 18 remained H. pylori positive (38.9% cured). Pretherapeutic metronidazole resistance was associated with a lower probability of eradication success (10% vs. 75%, p= .04). Ten of these 11 patients agreed to be retreated by PPI-B-T-F. Final cure of H. pylori with PPI-B-T-F was achieved in 9/10 patients (90%) nonresponsive to PPI-B-T-M. Conclusions. In the presence of metronidazole resistance, PPI-B-T-M as a recommended second-line therapy by the Maastricht consensus conference achieved unacceptable low cure rates in our metronidazole pretreated population. In this population, metronidazole based second-line quadruple therapy may be best suited in case of a metronidazole-free first line-regimen (e.g. PPI-clarithromycin-amoxicillin) or a low prevalence of metronidazole resistance. Furazolidone in the PPI-B-T-F combination does not have a cross-resistance potential to metronidazole and is a promising salvage option after a failed PPI-B-T-M regimen. [source] The HOMER Study: The Effect of Increasing the Dose of Metronidazole When Given with Omeprazole and Amoxicillin to Cure Helicobacter pylori InfectionHELICOBACTER, Issue 4 2000Karna Dev Bardhan Background.Helicobacter pylori eradication with omeprazole, amoxycillin, and metronidazole is both effective and inexpensive. However, eradication rates with different dosages and dosing vary, and data on the impact of resistance are sparse. In this study, three different dosages of omeprazole, amoxycillin, and metronidazole were compared, and the influence of metronidazole resistance on eradication was assessed. Methods. Patients (n = 394) with a positive H. pylori screening test result and endoscopy-proven duodenal ulcer in the past were enrolled into a multicenter study performed in four European countries and Canada. After baseline endoscopy, patients were randomly assigned to treatment for 1 week with either omeprazole, 20 mg twice daily, plus amoxycillin, 1,000 mg twice daily, plus metronidazole, 400 mg twice daily (low M); or omeprazole, 40 mg once daily, plus amoxycillin, 500 mg three times daily, plus metronidazole, 400 mg three times daily (medium M); or omeprazole, 20 mg twice daily, plus amoxycillin, 1,000 mg twice daily, plus metronidazole, 800 mg twice daily (high M). H. pylori status at entry was assessed by a 13C urea breath test and a culture. Eradication was defined as two negative 13C-urea breath test results 4 and 8 weeks after therapy. Susceptibility testing using the agar dilution method was performed at entry and in patients with persistent infection after therapy. Results. The eradication rates, in terms of intention to treat (ITT) (population n = 379) (and 95% confidence interval [CI]) were as follows: low M 76% (68%, 84%), medium M 76% (68%, 84%), and high M 83% (75%, 89%). By per-protocol analysis (population n = 348), the corresponding eradication rates were: low M 81%, medium M 80%, and high M 85%. No H. pylori strains were found to be resistant to amoxycillin. Prestudy resistance of H. pylori strains to metronidazole was found in 72 of 348 (21%) of the cultures at entry (range, 10%,39% in the five countries). The overall eradication rate in prestudy metronidazole-susceptible strains was 232 of 266 (87%) and, for resistant strains, it was 41 of 70 (57%; p < .001). Within each group, the results were as follows (susceptible/resistant): low M, 85%/54%; medium M, 86%/50%; and high M, 90%/75%. There were no statistically significant differences among the treatment groups. 23 strains susceptible to metronidazole before treatment were recultured after therapy failed; 20 of these had now developed resistance. Conclusions.H. pylori eradication rates were similar (approximately 80%) with all three regimens. Metronidazole resistance reduced efficacy; increasing the dose of metronidazole appeared not to overcome the problem or significantly improve the outcome. Treatment failure was generally associated with either prestudy or acquired metronidazole resistance. These findings are of importance when attempting H. pylori eradication in communities with high levels of metronidazole resistance. [source] Analysis of drug resistance and virulence-factor genotype of Irish Helicobacter pylori strains: is there any relationship between resistance to metronidazole and cagA status?ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 7 2009I. TANEIKE Summary Background,Helicobacter pylori infection is eradicated with antimicrobial agents and drug-resistant strains make successful treatment difficult. Geographical variations in virulence-factor genotype also exist. Aim, To evaluate prevalence of drug resistance and virulence-factor genotype in Irish H. pylori strains and to investigate if there is any relationship between drug resistance and genotype. Methods,Helicobacter pylori strains isolated from 103 patients were examined. Antimicrobial susceptibilities were tested by Etest. The virulence-factor genotypes were determined using PCR. Frequencies of spontaneous metronidazole-resistance were measured in vitro. Results, Metronidazole resistance was present in 37.9% of strains examined. 16.5% of strains were clarithromycin-resistant and resistance to both agents observed was found in 12.6% of strains. 68% of strains were cagA+. The dominant vacA type was s1/m2, followed by s1/m1 and s2/m2. The metronidazole resistance rate in cagA, group was significantly higher than in cagA+ (P = 0.0089). Spontaneous resistance to metronidazole in cagA, occurred in higher frequency when compared with cagA+. Conclusions,cagA+ and vacAs1/m2 type was the dominant genotype in Irish H. pylori strains. Significant rates of metronidazole resistance were observed in cagA, group. cagA, strains tend to acquire metronidazole resistance in vitro. Absence of cagA might be a risk factor in development of metronidazole resistance. [source] High prevalence and level of resistance to metronidazole, but lack of resistance to other antimicrobials in Helicobacter pylori, isolated from a multiracial population in KuwaitALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2006M. JOHN ALBERT Summary Background The primary treatment regimen for Helicobacter pylori infection for Kuwaitis does not contain metronidazole, but that for expatriates does. There is also increasing failure of antimicrobial therapy. Aim To determine the susceptibility of H. pylori from upper gastrointestinal biopsies of Kuwaitis and non-Kuwaitis to find out if differences existed in the susceptibilities of the isolates from the two different populations. Methods The susceptibilities of 96 H. pylori isolates were tested against metronidazole, amoxicillin, clarithromycin and tetracycline by the E test. The rdxA gene was analysed from selected metronidazole-susceptible and metronidazole-resistant strains to find out polymorphism and the basis of metronidazole resistance. Results Approximately, 70% of isolates from both populations were metronidazole resistant with 65% isolates showing high minimum inhibitory concentration values of >256 ,g/mL. No resistance to the other three antimicrobials was found. There were novel nonsense and missense mutations with no deletion in the rdxA gene by insertion of mini-IS605. Conclusions The prevalence and level of metronidazole resistance in H. pylori in the two populations was high with no difference, in spite of different treatment regimens. Metronidazole resistance in this transitional country appeared to be independent of prior metronidazole use for treatment of H. pylori infection. [source] Meta-analysis: the efficacy, adverse events, and adherence related to first-line anti- Helicobacter pylori quadruple therapiesALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2004L. A. Fischbach Summary Background :,Owing to rising drug-resistant Helicobacter pylori infections, currently recommended proton-pump inhibitor-based triple therapies are losing their efficacy, and regimens efficacious in the presence of drug resistance are needed. Aims :,To summarize the efficacy, safety and adherence of first-line quadruple H. pylori therapies in adults. Methods :,Meta-regression models identified factors explaining variation in the efficacy of first-line quadruple therapies from 145 treatment arms. Estimates of average efficacy were calculated within homogeneous groups. Results :,Quadruple therapy containing a gastric acid inhibitor, bismuth, metronidazole and tetracycline was enhanced when omeprazole was included, treatment duration lasted 10,14 days, and when therapy took place in the Netherlands, Hong Kong and Australia. Treatment efficacy decreased as the prevalence of metronidazole resistance increased. Even in areas with a high prevalence of metronidazole resistance, this quadruple regimen eradicated more than 85% of H. pylori infections when it contained omeprazole and was given for 10,14 days. Furthermore, in the presence of clarithromycin resistance, this quadruple regimen eradicated 90,100% of H. pylori infections, while the currently recommended triple therapy containing clarithromycin, amoxicillin and a proton-pump inhibitor eradicated only 25,61% (P < 0.001). Adherence and adverse events for quadruple therapy were similar to currently recommended triple therapies. Conclusions :,Guidelines should include quadruple therapy with a proton-pump inhibitor, a bismuth compound, metronidazole and tetracycline among recommended first-line anti- H. pylori therapies. [source] Primary Helicobacter pylori resistance to metronidazole and clarithromycin in the Finnish populationALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2004T. T. Koivisto Summary Aim :,To systematically determine Helicobacter pylori primary antimicrobial resistance in Finland and the associated demographic and clinical features. Methods :,A total of 342 adult patients referred for gastroscopy at 23 centres in different parts of Finland and positive for the rapid biopsy urease test were recruited. Clinical and demographic data were collected via a structured questionnaire. Patients with positive H. pylori culture and successful antibiotic sensitivity determination by the E -test method (n = 292) were included in the present analysis. Results :,The study population consisted of 134 men and 158 women, mean age 56 years (95% CI, 55,58 years). Resistance to metronidazole was 38% (110 of 292) and to clarithromycin 2% (seven of 292). Resistance to metronidazole was higher in women than in men (48% vs. 25%, P < 0.001). Previous use of antibiotics for gynaecological infections predicted metronidazole resistance (P = 0.01), and previous use of antibiotics for respiratory (P = 0.02) and dental infections (P = 0.02) the clarithromycin resistance. We observed no major geographical variations in metronidazole resistance. Conclusions :,The primary metronidazole resistance of H. pylori was 38% and was common in women previously treated for gynaecological infections. Primary clarithromycin resistance was uncommon (2%) and may associate with previous dental and respiratory infections. [source] One-week ranitidine bismuth citrate, amoxicillin and metronidazole triple therapy for the treatment of Helicobacter pylori infection in ChineseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 12 2002W. K. Hung Summary Background : We have previously shown that ranitidine bismuth citrate-based, clarithromycin-containing triple therapy achieves a higher eradication rate than proton pump inhibitor-based regimens in areas with a high prevalence of metronidazole resistance. Aim : To evaluate whether this higher efficacy of ranitidine bismuth citrate over proton pump inhibitor can be extended to non-clarithromycin-containing regimens. Methods : Helicobacter pylori -positive dyspeptic patients were randomized to receive either ranitidine bismuth citrate, 400 mg, amoxicillin, 1000 mg, and metronidazole, 400 mg, or omeprazole, 20 mg, amoxicillin, 1000 mg, and metronidazole, 400 mg, each given twice daily for 1 week. H. pylori eradication was confirmed by 13C-urea breath test 5 weeks later. The side-effects of the treatments were documented. Results : Two hundred and twenty-nine patients were eligible for analysis. By intention-to-treat and per protocol analysis, the eradication rates were 77% and 79%, respectively, in the ranitidine bismuth citrate,amoxicillin,metronidazole group and 77% and 82%, respectively, in the omeprazole,amoxicillin,metronidazole group (P = 0.58 and P = 0.65). However, patients in the omeprazole,amoxicillin,metronidazole group reported a significantly higher incidence of minor side-effects when compared to those in the ranitidine bismuth citrate,amoxicillin,metronidazole group (P = 0.001). Conclusions : Ranitidine bismuth citrate,amoxicillin,metronidazole was equally as effective as omeprazole,amoxicillin,metronidazole triple therapy, and may be considered as an alternative non-clarithromycin-based regimen in the Chinese population. [source] Helicobacter pylori antimicrobial resistance in the United Kingdom: the effect of age, sex and socio-economic statusALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2001H. K. Parsons Background: Helicobacter pylori antimicrobial resistance is the most common reason for eradication failure. Small studies have shown metronidazole resistance to be more prevalent in certain population groups. Aim: To determine the resistance rates in a large cohort of patients from a single centre in the UK, and to evaluate resistance patterns over time, according to age, sex and socio-economic status. Methods: Consecutive patients with H. pylori -positive antral gastric biopsy samples were studied from 1994 to 1999. Susceptibility testing was performed to metronidazole, tetracycline, macrolide and amoxicillin by the modified disk diffusion method. The Jarman under-privileged area score was used as a measure of socio-economic status. Results: A total of 1064 patients were studied. Overall metronidazole resistance was 40.3%, decreasing with age (P < 0.0001, odds ratio for patients over 60 years 0.63, 95% CI: 0.48,0.80). Women were more likely to have metronidazole resistant strains (P=0.003, odds ratio 1.5, 95% CI: 1.15,1.91), but there was no association with Jarman score. Macrolide resistance was associated with metronidazole resistance (P=0.03, odds ratio 2.14, 95% CI: 1.07,4.28). Conclusions: Metronidazole resistance in H. pylori is highly prevalent and more common in women and the young, but does not appear to be related to socio-economic status. [source] Nitrofurantoin quadruple therapy for Helicobacter pylori infection: effect of metronidazole resistanceALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2001D. Y. Graham Background: Antibiotic resistance has increasingly been recognized as the major cause of treatment failure for Helicobacter pylori infection. New therapies for patients with metronidazole- or clarithromycin-resistant H. pylori are needed. Aim: To investigate the role of nitrofurantoin quadruple therapy for the treatment of H. pylori. Methods: Patients with confirmed H. pylori infection received nitrofurantoin (100 mg t.d.s.), omeprazole (20 mg b.d.), Pepto-Bismol (two tablets t.d.s.), and tetracycline (500 mg t.d.s.) for 14 days. Four or more weeks after the end of therapy, outcome was assessed by repeat endoscopy with histology and culture or urea breath testing. Results: Thirty patients were entered, including 25 men and five women; the mean age was 54.9 years. The most common diagnoses were duodenal ulcer (23%) and GERD (18%). The intention-to-treat cure rate was 70% (95% CI: 50.6,85%). Nitrofurantoin quadruple therapy was more effective with metronidazole-sensitive strains (88%; 15 out of 17) than with metronidazole-resistant strains (33%; three out of nine; P=0.008). Two of the treatment failures had pre-treatment isolates susceptible to metronidazole, which were resistant after therapy. Conclusions: Because nitrofurantoin quadruple therapy performed inadequately in the presence of metronidazole resistance, we conclude that nitrofurantoin is unlikely to find clinical utility for the eradication of H. pylori. [source] Metronidazole containing quadruple therapy for infection with metronidazole resistant Helicobacter pylori: a prospective studyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2000Graham Background: Metronidazole remains a key component of H. pylori infection therapy. It has been suggested that despite resistance, metronidazole may be effective when given at high dose with bismuth, tetracycline, and a proton pump inhibitor (quadruple therapy). Aim: To prospectively evaluate metronidazole quadruple therapy for treatment of metronidazole resistant H. pylori infection in the United States. Methods: Patients infected with metronidazole resistant H. pylori were prospectively prescribed 14 days of quadruple therapy consisting of metronidazole 500 mg t.d.s., tetracycline 500 mg q.d.s., two bismuth subsalicylate tablets q.d.s., and omeprazole 20 mg o.d. Results: A total of 26 patients were entered into the study; 22 for their first treatment and four as re-treatment for failed therapy. Of the 26 patients, 24 were cured (cure rate 92%; 95% CI: 78,99%). Both treatment failures reported full compliance to 14 days of therapy. Side-effects were common and resulted in premature discontinuation of therapy in 31%. Premature discontinuation did not reduce the cure rate. Conclusion: Quadruple metronidazole combination therapy is effective despite the presence of metronidazole resistance and should be considered as either first line therapy or for failures of twice-a-day combination therapies. [source] Anti- Helicobacter pylori activity of Chinese tea: in vitro studyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2000Yuk-Kei Yee Background: Chinese tea has an antibacterial activity against a wide range of bacteria. However, its activity against Helicobacter pylori has not been reported. Method: In this study the anti- Helicobacter pylori effects of a Chinese tea (Lung Chen tea), and two tea catechins, epigallocatechin gallate and epicatechin and their minimum inhibitory concentrations (MICs) were examined. The effect of Lung Chen on metronidazole resistance was also studied using the E -test. Results: Lung Chen, epigallocatechin gallate and epicatechin all inhibited the growth of H. pylori. The MIC90 for Lung Chen was 0.25,0.5% (w/w) and that of epigallocatechin gallate and epicatechin were 50,100 and 800,1600 ,g/mL, respectively. Epigallocatechin gallate is probably the active ingredient responsible for most of the anti- H. pylori activity of Chinese tea. Lung Chen did not reverse metronidazole resistance. Conclusions: Chinese tea has anti- H. pylori activity in a daily consumed concentration, and epigallocatechin gallate is probably the active ingredient responsible for the action. [source] | ||||||||||