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Clarithromycin Resistance (clarithromycin + resistance)
Selected AbstractsEvaluation of Clarithromycin Resistance in Helicobacter pylori Obtained from Culture Isolates, Gastric Juice, and FecesHELICOBACTER, Issue 2 2009Emiko Rimbara No abstract is available for this article. [source] Clarithromycin Resistance in Iranian H. pylori Strains Before Introduction of ClarithromycinHELICOBACTER, Issue 1 2003Marjan Mohammadi No abstract is available for this article. [source] Clarithromycin resistance in Helicobacter pylori infection: Does it matter?JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2000Kwong Ming Fock First page of article [source] Primary clarithromycin resistance in Italy assessed on Helicobacter pylori DNA sequences by TaqMan real-time polymerase chain reactionALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 3 2006V. DE FRANCESCO Summary Background Helicobacter pylori clarithromycin resistance is increasing worldwide and different mutations are involved in its mechanisms. Recently, molecular methods have been proposed to assess these mutations. Aim To assess prevalence of primary clarithromycin resistance in two Italian areas, and the distribution of involved mutations, by using a novel method for real-time polymerase chain reaction. Methods Two hundred and thirty-two H. pylori -positive patients undergoing oesophagogastroduodenoscopy in two Italian towns (Rome, centre Italy; Foggia, south Italy) were enrolled. Helicobacter pylori infection was detected by histology, rapid urease and urea breath tests. Clarithromycin resistance was assessed by TaqMan real-time polymerase chain reaction on paraffin-embedded antral biopsies. Results Primary clarithromycin resistance was detected in 62 (26.7%) patients. Its prevalence did not differ between the two areas (31.5%, centre vs. 23.3%, south; P = 0.17) and between non-ulcer dyspepsia and peptic ulcer patients (28.4% vs. 20.7%, P = 0.2). The A2143G point mutation was detected in 35 (56.4%) patients, A2142G in 14 (22.6%), A2142C in eight (12.9%), whilst a double mutation (A2143G plus A2142C or A2142G) was present in the remaining five (8.1%) cases. Conclusions Our study found that primary clarithromycin resistance is highly prevalent in both central and southern Italy, and that A2143G is the most frequent point mutation involved in these areas. [source] Annual Change of Primary Resistance to Clarithromycin among Helicobacter pylori Isolates from 1996 through 2008 in JapanHELICOBACTER, Issue 5 2009Noriyuki Horiki Abstract Background:, Recent studies have shown that the combination of proton pump inhibitor, amoxicillin and clarithromycin is one of the best choices for Helicobacter pylori eradication therapy. However, increasing number of cases of H. pylori infection showing resistance to clarithromycin therapy has been reported and this is currently the main cause of eradication failure. We investigated the annual changes of the antimicrobial susceptibility to clarithromycin, amoxicillin and minocycline during a period of 12 years in Japan. Methods:, This study comprised 3521 patients (mean age (SD), 55.4 (13.7) years-old, 2467 males and 1054 females) positive for H. pylori as assessed by microaerobic bacterial culture from 1996 through 2008. All patients were previously untreated for H. pylori and were enrolled in the study to assess primary resistance to the three antibiotics. Results:, The overall primary resistance to clarithromycin, amoxicillin and minocycline were 16.4%, (577/3521), 0.03% (1/3521) and 0.06% (2/3521), respectively. From1996 through 2004, the resistance rate to clarithromycin increased gradually to approximately 30% and then it remained without marked fluctuation since 2004. Analysis by gender showed a significant increase (p < .0001) in resistance rate to clarithromycin among females (217/1057, 20.6%) compared to males (360/2467, 14.6%). Analysis by age, disclosed significantly (p < .0001) higher resistance rate to clarithromycin in patients of more than 65-years-old compared to the younger population. Conclusions:, The resistance rate of H. pylori infection to clarithromycin in Japan has increased gradually to approximately 30% from 1996 through 2004, and remained unchanged since 2004. Elderly and females were at high risk of having resistance to clarithromycin. Our results suggested that the level of clarithromycin resistance in Japan has now risen to the point where it should no longer be used as empiric therapy. [source] Diagnosis of Helicobacter pylori InfectionHELICOBACTER, Issue 2009Lurdes Monteiro Abstract The articles published this last year in the field of Helicobacter pylori diagnosis reported the development of in vivo histology, small improvements in some invasive methods (urease test, culture, and histology) and new kits for the stool antigen tests. They also contributed to increasing our knowledge, by further exploration into specific conditions for the urea breath test and into the significance of cagA antibodies. The role of serum markers of atrophy was also confirmed. Molecular methods are still being developed for direct genotyping, detection of H. pylori and its clarithromycin resistance, either by polymerase chain reaction or fluorescent in-situ hybridization. For the first time, there was a report on a possible interest of magnetic resonance spectroscopy. [source] Diagnosis of Helicobacter pyloriHELICOBACTER, Issue 2008Marta Granstrom Abstract The different invasive and noninvasive diagnostic tests for Helicobacter pylori have been applied mainly in emerging countries. Molecular methods have been developed, especially a test for detection of H. pylori and its clarithromycin resistance directly from stools. The long-term effects of eradication on histologic lesions have been studied in a meta-analysis and the prognostic value of post-treatment in gastric mucosa-associated lymphoid tissue lymphoma has been assessed. An operating link for gastritis assessment (the OLGA staging) has also been published. Attempts to simplify the urea breath test protocol have been made, and new stool antigen tests have been proposed and compared to those previously available. [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] Clinical trial: clarithromycin vs. levofloxacin in first-line triple and sequential regimens for Helicobacter pylori eradicationALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2010J. MOLINA-INFANTE Aliment Pharmacol Ther,31, 1077,1084 Summary Background,Helicobacter pylori eradication rates with standard triple therapy have declined to unacceptable levels. Aim, To compare clarithromycin and levofloxacin in triple and sequential first-line regimens. Methods, A total of 460 patients were randomized into four 10-day therapeutic schemes (115 patients per group): (i) standard OCA, omeprazole, clarithromycin and amoxicillin; (ii) triple OLA, omeprazole, levofloxacin and amoxicillin; (iii) sequential OACM, omeprazole plus amoxicillin for 5 days, followed by omeprazole plus clarithromycin plus metronidazole for 5 days; and (iv) modified sequential OALM, using levofloxacin instead of clarithromycin. Eradication was confirmed by 13C-urea breath test. Adverse effects and compliance were assessed by a questionnaire. Results, Per protocol cure rates were: OCA (66%; 95% CI: 57,74%), OLA (82.6%; 75,89%), OACM (80.8%; 73,88%) and OALM (85.2%; 78,91%). Intention-to-treat cure rates were: OCA (64%; 55,73%), OLA (80.8%; 73,88%), OACM (76.5%; 69,85%) and OALM (82.5%; 75,89%). Eradication rates were lower with OCA than with all the other regimens (P < 0.05). No differences in compliance or adverse effects were demonstrated among treatments. Conclusions, Levofloxacin-based and sequential therapy are superior to standard triple scheme as first-line regimens in a setting with high clarithromycin resistance. However, all of these therapies still have a 20% failure rate. [source] Primary clarithromycin resistance in Italy assessed on Helicobacter pylori DNA sequences by TaqMan real-time polymerase chain reactionALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 3 2006V. DE FRANCESCO Summary Background Helicobacter pylori clarithromycin resistance is increasing worldwide and different mutations are involved in its mechanisms. Recently, molecular methods have been proposed to assess these mutations. Aim To assess prevalence of primary clarithromycin resistance in two Italian areas, and the distribution of involved mutations, by using a novel method for real-time polymerase chain reaction. Methods Two hundred and thirty-two H. pylori -positive patients undergoing oesophagogastroduodenoscopy in two Italian towns (Rome, centre Italy; Foggia, south Italy) were enrolled. Helicobacter pylori infection was detected by histology, rapid urease and urea breath tests. Clarithromycin resistance was assessed by TaqMan real-time polymerase chain reaction on paraffin-embedded antral biopsies. Results Primary clarithromycin resistance was detected in 62 (26.7%) patients. Its prevalence did not differ between the two areas (31.5%, centre vs. 23.3%, south; P = 0.17) and between non-ulcer dyspepsia and peptic ulcer patients (28.4% vs. 20.7%, P = 0.2). The A2143G point mutation was detected in 35 (56.4%) patients, A2142G in 14 (22.6%), A2142C in eight (12.9%), whilst a double mutation (A2143G plus A2142C or A2142G) was present in the remaining five (8.1%) cases. Conclusions Our study found that primary clarithromycin resistance is highly prevalent in both central and southern Italy, and that A2143G is the most frequent point mutation involved in these areas. [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] | ||||||||||