Increasing Multidrug Resistance in Helicobacter pylori Strains Isolated from Children and Adults in Mexico (original) (raw)

[High percentage of clarithromycin and metronidazole resistance in Helicobacter pylori clinical isolates obtained from Spanish children]

Revista española de quimioterapia : publicación oficial de la Sociedad Española de Quimioterapia, 2009

To determine the primary and secondary resistance to several antimicrobial agents in Spanish Helicobacter pylori clinical isolates obtained from paediatric patients from January 2002 to June 2006. Samples were collected from gastric biopsies of symptomatic paediatric patients and H. pylori cultured according to standard microbiological procedures. Resistance was determined by E-test. Strains were considered resistant if minimal inhibitory concentration (MIC) > or = 2 mg/l for amoxycillin, > or = 4 mg/l for tetracycline, > or = 8 mg/l for metronidazole, > or = 1 mg/l for clarithromycin, MIC > or = 4 mg/l for ciprofloxacin, MIC > or = 32 mg/l for rifampicin and intermediate if MIC = 0.5 mg/l for clarithromycin, and MIC = 2 mg/l for ciprofloxacin. A total of 101 patients were included: 38 males and 63 females (sex ratio M/F: 0.6). Average age was 10 years (range: 4-18 years). All strains were susceptible to amoxycillin, tetracycline and rifampicin, 35.7% were resistan...

Prevalence of Helicobacter pylori Resistance to Metronidazole, Clarithromycin, Amoxicillin, Tetracycline, and Furazolidone in Brazil

Helicobacter, 2000

Helicobacter pylori infection is associated with a wide range of digestive diseases and is very prevalent in developing countries, although few data exist on the susceptibility of H. pylori to antimicrobials commonly used in eradication schedules in these countries. The aim of this study was to evaluate the resistance of H. pylori to metronidazole, clarithromycin, amoxicillin, tetracycline, and furazolidone in dyspeptic Brazilian patients. Material and Methods. Ninety consecutive H. pyloripositive patients were enrolled. Resistance was evaluated by an agar dilution test. Results. Resistance to metronidazole was detected in 38 patients (42%); to amoxicillin in 26 individuals (29%); to clarithromycin in 6 patients (7%); to tetracycline in 6 patients (7%); and to furazolidone in 4 individuals (4%). Thirteen strains were resistant to two agents, and eight strains were resistant to three antimicrobials. Conclusions. These results confirm the need for culture and susceptibility testing to define H. pylori resistance patterns in particular geographical areas before the general use of an eradication schedule. They also suggest the possibility of resistance to such antimicrobials as amoxicillin or tetracycline in geographical areas with a high prevalence of H. pylori infection and still not fully evaluated for antimicrobial susceptibility.

Prevalence of Helicobacter pylori resistance to metronidazole, clarithromycin, amoxycillin, tetracycline, and furazolidone in brazil

Gastroenterology, 2000

Helicobacter pylori infection is associated with a wide range of digestive diseases and is very prevalent in developing countries, although few data exist on the susceptibility of H. pylori to antimicrobials commonly used in eradication schedules in these countries. The aim of this study was to evaluate the resistance of H. pylori to metronidazole, clarithromycin, amoxicillin, tetracycline, and furazolidone in dyspeptic Brazilian patients. Material and Methods. Ninety consecutive H. pyloripositive patients were enrolled. Resistance was evaluated by an agar dilution test. Results. Resistance to metronidazole was detected in 38 patients (42%); to amoxicillin in 26 individuals (29%); to clarithromycin in 6 patients (7%); to tetracycline in 6 patients (7%); and to furazolidone in 4 individuals (4%). Thirteen strains were resistant to two agents, and eight strains were resistant to three antimicrobials. Conclusions. These results confirm the need for culture and susceptibility testing to define H. pylori resistance patterns in particular geographical areas before the general use of an eradication schedule. They also suggest the possibility of resistance to such antimicrobials as amoxicillin or tetracycline in geographical areas with a high prevalence of H. pylori infection and still not fully evaluated for antimicrobial susceptibility.

RESISTANCE TO AMOXICILLIN, CLARITHROMYCIN AND CIPROFLOXACIN OF Helicobacter pylori ISOLATED FROM SOUTHERN BRAZIL PATIENTS

Introduction: Helicobacter pylori is a bacteria which infects half the world population and is an important cause of gastric cancer. The eradication therapy is not always effective because resistance to antimicrobials may occur. The aim of this study was to determine the susceptibility profile of H. pylori to amoxicillin, clarithromycin and ciprofloxacin in the population of Southern Brazil. Material and methods: Fifty four samples of H. pylori were evaluated. The antibiotics susceptibility was determined according to the guidelines of the British Society for Antimicrobial Chemotherapy and the Comité de l’Antibiogramme de la Société Française de Microbiologie. Results: Six (11.1%) H. pylori isolates were resistant to clarithromycin, one (1.9%) to amoxicillin and three (5.5%) to ciprofloxacin. These indices of resistance are considered satisfactory and show that all of these antibiotics can be used in the empirical therapy. Conclusion: The antibiotics amoxicillin and clarithromycin are still a good option for first line anti-H. pylori treatment in the population of Southern Brazil.

The Problem of Helicobacter pylori Resistance to Antibiotics: A Systematic Review in Latin America

American Journal of Gastroenterology, 2014

The American Journal of GASTROENTEROLOGY nature publishing group 485 REVIEW CLINICAL AND SYSTEMATIC REVIEWS INTRODUCTION Chronic Helicobacter pylori infection is causally related to serious benign and malignant upper gastrointestinal diseases, including peptic ulcer, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer (1). Conversely, eradication of H. pylori is associated with ulcer healing (2), regression of mucosa-associated associated lymphoid tissue lymphoma (3), and decreased cancer risk (4). Successful treatment for H. pylori infection requires multidrug regimens, which are frequently based on clarithromycin as the central component. Eradication rates vary with level of antibiotic resistance (5,6), and, according to one guideline (7), the use of clarithromycin without susceptibility testing is not recommended in populations with more than 15-20 % prevalence of resistant isolates. Many Latin American countries have a high burden of H. pylori infection (8,9) and associated diseases, particularly gastric cancer (10). Th is geographic region also has multiple avenues of unfettered access to antibiotics, including selfmedication, unnecessary prescriptions, and lax regulation of sales (11). In order to guide treatment choice and tailor eradication

Antibiotic resistance among Helicobacter pylori clinical isolates in Lima, Peru

Infection and Drug Resistance, 2017

Objectives: Gastric carcinoma is the most common cancer and cause of cancer mortality in Peru. Helicobacter pylori, a bacterium that colonizes the human stomach, is a Group 1 carcinogen due to its causal relationship to gastric carcinoma. While eradication of H. pylori can help prevent gastric cancer, characterizing regional antibiotic resistance patterns is necessary to determine targeted treatment for each region. Thus, we examined primary antibiotic resistance in clinical isolates of H. pylori in Lima, Peru. Materials and methods: H. pylori strains were isolated from gastric biopsies of patients with histologically proven H. pylori infection. Primary antibiotic resistance among isolates was examined using E-test strips. Isolates were examined for the presence of the cagA pathogenicity island and the vacA m1/m2 alleles via polymerase chain reaction. Results: Seventy-six isolates were recovered from gastric biopsies. Clinical isolates showed evidence of antibiotic resistance to 1 (27.6%, n=21/76), 2 (28.9%, n=22/76), or ≥3 antibiotics (40.8%). Of 76 isolates, eight (10.5%) were resistant to amoxicillin and clarithromycin, which are part of the standard triple therapy for H. pylori infection. No trends were seen between the presence of cagA, vacA m1, or vacA m2 and antibiotic resistance. Conclusion: The rate of antibiotic resistance among H. pylori isolates in Lima, Peru, is higher than expected and presents cause for concern. To develop more targeted eradication therapies for H. pylori in Peru, more research is needed to better characterize antibiotic resistance among a larger number of clinical isolates prospectively.

Prospective multicentre study on antibiotic resistance of Helicobacter pylori strains obtained from children living in Europe

Gut, 2006

To prospectively assess the antibacterial resistance rate in Helicobacter pylori strains obtained from symptomatic children in Europe. Methods: During a 4-year period, 17 paediatric centres from 14 European countries reported prospectively on patients infected with H pylori, for whom antibiotic susceptibility was tested. Results: A total of 1233 patients were reported from Northern (3%), Western (70%), Eastern (9%) and Southern Europe (18%); 41% originated from outside Europe as indicated by mother's birth-country; 13% were ,6 years of age, 43% 6-11 years of age and 44% .11 years of age. Testing was carried out before the first treatment (group A, n = 1037), and after treatment failure (group B, n = 196). Overall resistance to clarithromycin was detected in 24% (mean, A: 20%, B: 42%). The primary clarithromycin resistance rate was higher in boys (odds ratio (OR) 1.58; 1.12 to 2.24, p = 0.01), in children ,6 years compared with .12 years (OR 1.82, 1.10 to 3.03, p = 0.020) and in patients living in Southern Europe compared with those living in Northern Europe (OR 2.25; 1.52 to 3.30, p,0.001). Overall resistance rate to metronidazole was 25% (A: 23%, B: 35%) and higher in children born outside Europe (A: adjusted. OR 2.42, 95% CI: 1.61 to 3.66, p,0.001). Resistance to both antibiotics occurred in 6.9% (A: 5.3%, B: 15.3%). Resistance to amoxicillin was exceptional (0.6%). Children with peptic ulcer disease (80/1180, 6.8%) were older than patients without ulcer (p = 0.001). Conclusion: The primary resistance rate of H pylori strains obtained from unselected children in Europe is high. The use of antibiotics for other indications seems to be the major risk factor for development of primary resistance.

High Levels of Resistance to Metronidazole and Clarithromycin in Helicobacter pylori Strains in Children

Journal of Clinical Microbiology, 2001

The aim of the study was to evaluate the prevalence of resistance to amoxicillin, metronidazole, and clarithromycin before treatment of Helicobacter pylori infection in children and to assess the evolution of resistance with time. The study was carried out between 1994 and 1999 with 150 H. pylori-positive children through gastric culture (antimicrobial susceptibility) and histology. All cultured H. pylori strains were sensitive to amoxicillin, 64 (43%) were resistant to metronidazole, 32 (21%) were resistant to clarithromycin, and 14 (9%) were resistant to both metronidazole and clarithromycin. The overall prevalence of resistance to metronidazole and clarithromycin did not change significantly with time. The study highlights the generalized high-level and stable metronidazole and clarithromycin resistance of H. pylori strains from children.