scholarly journals Application of Visual Gene Clip-Based Tailored Therapy for the Eradication of Helicobacter pylori

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Lili Yang ◽  
Ao Zou ◽  
Huihua Wu ◽  
Hai Guo ◽  
Fangting Zhang ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Confidence Interval ◽  
Acid Secretion ◽  
Antimicrobial Agents ◽  
Point Mutations ◽  
Eradication Therapy ◽  
23S Rrna ◽  
Tailored Therapy ◽  
H Pylori

Background. Helicobacter pylori eradication with therapies employing a proton pump inhibitor (PPI) and antimicrobial agents is mainly achieved via bacterial susceptibility to antimicrobial agents and the magnitude of acid secretion inhibition. However, annual eradication rates have greatly declined in Mainland China, and therefore, tailored H. pylori eradication regimens that inhibit acid secretion and employ optimal antimicrobial agents determined based on gene clip testing may improve eradication rates. This study was aimed at evaluating the efficacy of tailored H. pylori eradication therapy guided by visual gene clip testing for antibiotic resistance and PPI metabolism genotypes. Methods. This prospective study included 244 patients (141 men and 103 women aged 20–79 years) receiving initial treatment for H. pylori infection. Visual gene clip testing using gastric mucosal specimens was performed to detect antibiotic resistance to clarithromycin conferred by the A2142G and A2143G point mutations of the H. pylori 23S rRNA gene and to levofloxacin conferred by the Asn87 and Asp91 point mutations of the H. pylori gyrA gene. Patients received a 14-day bismuth quadruple therapy regimen guided by testing for antibiotic resistance and CYP2C19 polymorphisms, and primary H. pylori eradication was assessed at least 4 weeks after therapy. Results. H. pylori strains were successfully isolated from the gastric mucosa tissues of 244 patients. Antibiotic resistant isolates were identified in 63 patients, with clarithromycin resistance observed in 50 patients, levofloxacin resistance in 7 patients, and dual resistance in 6 patients. The PPI metabolic genotype of CYP2C19 was detected in 242 of 244 cases, and 97 cases were categorized as extensive metabolizers, 141 as intermediate metabolizers, and 4 as poor metabolizers. Among the 242 patients who received tailored therapy, the H. pylori eradication rate was 90.9% (95% confidence interval 87.3%~94.6%) in the intention-to-treat analysis and 96.9% (95% confidence interval 94.7%~99.2%) in the per protocol analysis. Conclusions. Tailored therapy for H. pylori infection guided by determination of antibiotic resistance and CYP2C19 polymorphism using visual gene chip technology may provide high clinical effectiveness as initial H. pylori eradication therapy.

scholarly journals Microarray-Based Detection and Clinical Evaluation for Helicobacter pylori Resistance to Clarithromycin or Levofloxacin and the Genotype of CYP2C19 in 1083 Patients

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Yi Song ◽  
Fengna Dou ◽  
Zhe Zhou ◽  
Ningmin Yang ◽  
Jing Zhong ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Limit Of Detection ◽  
Eradication Therapy ◽  
Gastric Biopsy ◽  
Individual Therapy ◽  
23S Rrna ◽  
Antibiotic Administration ◽  
Cyp2c19 Polymorphism ◽  
H Pylori

Background. Helicobacter pylori (H. pylori) is one of the most frequent and persistent bacterial infections that affect nearly half of the world’s population. Antibiotic resistance is a constantly evolving process and local surveillance of antibiotic resistance is warranted to guide clinicians in their choice of therapy. The aim of this study was to establish a microarray-based detection to identify H. pylori infection, clarithromycin and levofloxacin susceptibility, and CYP2C19 genetic polymorphism and guide to potential choice of proton pump inhibitor (PPI), antibiotic administration for tailored H. pylori eradication therapy. Methods. By analyzing the sequence of human genomic CYP2C19⁎2 and CYP2C19⁎3 and mutations within the 23S rRNA and gyrA gene regions conferring clarithromycin and levofloxacin resistance, respectively, we developed a microarray for individual therapy detection of H. pylori infection. Plasmids were established as positive or limit of detection (LOD) reference materials. The specificity and sensitivity of the microarray had been performed. And a total of 1083 gastric biopsy samples were tested and the Kappa value had been calculated between the array and Sanger sequencing. We also analyzed the resistance to clarithromycin and levofloxacin in China, as well as the CYP2C19 polymorphisms. Results. The LOD of detecting H. pylori was 103 CFU/mL and human genome DNA was 2 ng/μL. The detection results of 1083 gastric biopsy samples showed that 691 (63.80%) were H. pylori positive, of which 266 (38.49%) were resistant to clarithromycin, 192 (27.79%) were resistant to levofloxacin, and 61 (8.83%) were resistant to both of them. For the type of CYP2C19 polymorphism, 412 (38.04%) were homozygous fast type (HomEM), 574 (53%) were heterozygous EM (HetEM), and 97 (8.96%) were poor metabolizer (PM). Conclusions. The proposed microarray-based detection has high specificity, sensitivity, and reproducibility for detecting the resistance of clarithromycin or levofloxacin as well as CYP2C19 polymorphism, which may help to improve the clinical eradication rate of H. pylori.

scholarly journals Resistotype of Helicobacter pylori isolates: the impact on eradication outcome

2014 ◽  
Vol 63 (5) ◽  
pp. 703-709 ◽  
Author(s):  
Hanafiah Alfizah ◽  
Ahmad Norazah ◽  
Razlan Hamizah ◽  
Mohamed Ramelah
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Eradication Therapy ◽  
Fluoroquinolone Resistance ◽  
23S Rrna ◽  
Nonsense Mutations ◽  
Metronidazole Resistance ◽  
Resistant Strains ◽  
H Pylori ◽  
The Impact

Antibiotic resistance is increasing worldwide, and it has been regarded as the main factor reducing the efficacy of Helicobacter pylori therapy. The aim of this study was to determine the phenotype and genotype of antibiotic-resistant strains of H. pylori in the Malaysian population and to evaluate the impact of antibiotic resistance to eradication outcome. One hundred and sixty-one H. pylori isolates were analysed in this study. Metronidazole, clarithromycin, fluoroquinolone, amoxicillin and tetracycline susceptibilities were determined by Etest. PCR followed by DNA sequencing was carried out to determine mutations. The medical records of the patients infected with resistant strains were reviewed to determine the eradication outcome. Metronidazole resistance was encountered in 36.6 % of H. pylori isolates, whereas clarithromycin and fluoroquinolone resistance was observed in 1.2  and 1.9 % of isolates, respectively. All strains tested were susceptible to amoxicillin and tetracycline. Frameshift and nonsense mutations in rdxA and frxA genes resulting in stop codons contributed to metronidazole resistance, which leads to reduced eradication efficacy. A2142G and A2143G mutations of 23S rRNA were identified as causing failure of the eradication therapy. Mutation at either codon 87 or 91 of the gyrA gene was identified in fluoroquinolone-resistant strains. However, the effect of resistance could not be assessed. This study showed that frameshift and nonsense mutations in rdxA or frxA genes and point mutations in the 23S rRNA affected the efficacy of H. pylori eradication therapy.

scholarly journals Molecular genetic predictors of resistance to anti-Helicobacter pylori therapy

2017 ◽  
Vol 89 (8) ◽  
pp. 5-12 ◽  
Author(s):  
I V Maev ◽  
D N Andreev
Keyword(s):  
Helicobacter Pylori ◽  
Molecular Genetic ◽  
Point Mutations ◽  
Eradication Therapy ◽  
Empirical Therapy ◽  
Asian Population ◽  
23S Rrna ◽  
Specific Patient ◽  
Treatment Regimens ◽  
H Pylori

In current clinical practice, there is no optimal empirical therapy for Helicobacter pylori (H. pylori) infection and there is a progressive decrease in the efficiency of classical eradication therapy (ET) regimens. The variability in the efficiency of ET in a specific patient is largely due to the heterogeneous molecular genetic mechanisms underlying the resistance of the microorganism to the components of the treatment regimens. The basis of the mechanisms for antibiotic resistance in H. pylori is mainly the point mutations in some genes, which determine alterations in the mechanisms of action of drugs, such as clarithromycin (domain V of 23S rRNA), metronidazole (rdxA, frxA), amoxicillin (pbp1A), tetracycline (16S rRNA), and levofloxacin (gyrA). The predictors of resistance to ET are also the CagA-negative status of the microorganism and the presence of the vacA s2 allele. There are a number of host genetic determinants (the CYP2C19 genotype (*1/*1, *1/*17, *17/*17) and the MDR1 3435 T/T genotype (in an Asian population)) that reduce the efficiency of ET, by altering the pharmacokinetics of proton pump inhibitors. In addition, the IL-1β-511 C/C polymorphism that affects gastric acid secretion is a predictor of the inefficiency of ET.

scholarly journals Enzymic colorimetry-based DNA chip: a rapid and accurate assay for detecting mutations for clarithromycin resistance in the 23S rRNA gene of Helicobacter pylori

2009 ◽  
Vol 58 (11) ◽  
pp. 1443-1448 ◽  
Author(s):  
Shi-Hai Xuan ◽  
Yu-Gui Zhou ◽  
Bo Shao ◽  
Ya-Lin Cui ◽  
Jian Li ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Dna Sequencing ◽  
Point Mutations ◽  
Eradication Therapy ◽  
Dna Chip ◽  
23S Rrna ◽  
Rrna Gene ◽  
Direct Dna Sequencing ◽  
23S Rrna Gene ◽  
H Pylori

Macrolide drugs, such as clarithromycin (CAM), are a key component of many combination therapies used to eradicate Helicobacter pylori. However, resistance to CAM is increasing in H. pylori and is becoming a serious problem in H. pylori eradication therapy. CAM resistance in H. pylori is mostly due to point mutations (A2142G/C, A2143G) in the peptidyltransferase-encoding region of the 23S rRNA gene. In this study an enzymic colorimetry-based DNA chip was developed to analyse single-nucleotide polymorphisms of the 23S rRNA gene to determine the prevalence of mutations in CAM-related resistance in H. pylori-positive patients. The results of the colorimetric DNA chip were confirmed by direct DNA sequencing. In 63 samples, the incidence of the A2143G mutation was 17.46 % (11/63). The results of the colorimetric DNA chip were concordant with DNA sequencing in 96.83 % of results (61/63). The colorimetric DNA chip could detect wild-type and mutant signals at every site, even at a DNA concentration of 1.53×102 copies μl−1. Thus, the colorimetric DNA chip is a reliable assay for rapid and accurate detection of mutations in the 23S rRNA gene of H. pylori that lead to CAM-related resistance, directly from gastric tissues.

scholarly journals Genomic Analysis of Antimicrobial Resistance Genotype-to-Phenotype Agreement in Helicobacter pylori

2020 ◽  
Vol 9 (1) ◽  
pp. 2
Author(s):  
Tal Domanovich-Asor ◽  
Yair Motro ◽  
Boris Khalfin ◽  
Hillary A. Craddock ◽  
Avi Peretz ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antimicrobial Resistance ◽  
Point Mutations ◽  
Genomic Analysis ◽  
23S Rrna ◽  
Phenotype Correlation ◽  
Bioinformatics Pipeline ◽  
Phenotypic Resistance ◽  
Commercial Kits ◽  
H Pylori

Antimicrobial resistance (AMR) in Helicobacter pylori is increasing and can result in treatment failure and inappropriate antibiotic usage. This study used whole genome sequencing (WGS) to comprehensively analyze the H. pylori resistome and phylogeny in order to characterize Israeli H. pylori. Israeli H. pylori isolates (n = 48) underwent antimicrobial susceptibility testing (AST) against five antimicrobials and WGS analysis. Literature review identified 111 mutations reported to correlate with phenotypic resistance to these antimicrobials. Analysis was conducted via our in-house bioinformatics pipeline targeting point mutations in the relevant genes (pbp1A, 23S rRNA, gyrA, rdxA, frxA, and rpoB) in order to assess genotype-to-phenotype correlation. Resistance rates of study isolates were as follows: clarithromycin 54%, metronidazole 31%, amoxicillin 10%, rifampicin 4%, and levofloxacin 2%. Genotype-to-phenotype correlation was inconsistent; for every analyzed gene at least one phenotypically susceptible isolate was found to have a mutation previously associated with resistance. This was also observed regarding mutations commonly used in commercial kits to diagnose AMR in H. pylori cases. Furthermore, 11 novel point mutations associated with a resistant phenotype were detected. Analysis of a unique set of H. pylori isolates demonstrates that inferring resistance phenotypes from WGS in H. pylori remains challenging and should be optimized further.

scholarly journals Macrolide resistance in Helicobacter pylori: rapid detection of point mutations and assays of macrolide binding to ribosomes.

1997 ◽  
Vol 41 (12) ◽  
pp. 2724-2728 ◽  
Author(s):  
A Occhialini ◽  
M Urdaci ◽  
F Doucet-Populaire ◽  
C M Bébéar ◽  
H Lamouliatte ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Point Mutations ◽  
Restriction Enzymes ◽  
The United States ◽  
Drug Binding ◽  
Macrolide Resistance ◽  
Rrna Genes ◽  
23S Rrna ◽  
Dependent Manner ◽  
H Pylori

Resistance of Helicobacter pylori to macrolides is a major cause of failure of eradication therapies. Single base substitutions in the H. pylori 23S rRNA genes have been associated with macrolide resistance in the United States. Our goal was to extend this work to European strains, to determine the consequence of this mutation on erythromycin binding to H. pylori ribosomes, and to find a quick method to detect the mutation. Seven pairs of H. pylori strains were used, the parent strain being naturally susceptible to macrolides and the second strain having acquired an in vivo resistance during a treatment regimen that included clarithromycin. The identity of the strains was confirmed by random amplified polymorphic DNA testing with two different primers, indicating that resistance was the result of the selection of variants of the infecting strain. All resistant strains were found to have point mutations at position 2143 (three cases) or 2144 (four cases) but never on the opposite DNA fragment of domain V of the 23S rRNA gene. The mutation was A-->G in all cases except one (A-->C) at position 2143. Using BsaI and BbsI restriction enzymes on the amplified products, we confirmed the mutations of A-->G at positions 2144 and 2143, respectively. Macrolide binding was tested on purified ribosomes isolated from four pairs of strains with [14C]erythromycin. Erythromycin binding increased in a dose-dependent manner for the susceptible strain but not for the resistant one. In conclusion we suggest that the limited disruption of the peptidyltransferase loop conformation, caused by a point mutation, reduces drug binding and consequently confers resistance to macrolides. Finally, the macrolide resistance could be detected without sequencing by performing restriction fragment length polymorphism with appropriate restriction enzymes.

scholarly journals Phenotypic and Genotypic Analysis of Resistant Helicobacter pylori Strains Isolated from Children with Gastrointestinal Diseases

Diagnostics ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 759
Author(s):  
Monika Maria Biernat ◽  
Aldona Bińkowska ◽  
Łukasz Łaczmański ◽  
Paweł Biernat ◽  
Paweł Krzyżek ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Point Mutations ◽  
Gastrointestinal Diseases ◽  
Drug Susceptibility Testing ◽  
Test Method ◽  
Ulcer Disease ◽  
Genotypic Analysis ◽  
Clinical Diagnoses ◽  
H Pylori

Antibiotic resistance of Helicobacter pylori is currently a global issue. The aim of this study was to analyze actual antibiotic resistance rates of H. pylori strains isolated from children with primary infections and to compare the incidence of mutations that determine resistance to clarithromycin (CH) and metronidazole (MET) in children with different clinical diagnoses. A total of 91 H. pylori strains were isolated from 108 children with primary infections. Drug susceptibility testing of the strains was performed using E-test method. Classical sequencing of DNA fragments was used to detect point mutations for CH and MET resistance. Resistance to CH was detected in 31% of isolated strains (28/91), while resistance to MET and CH was detected in 35% (32/91) of strains. A2143G was the most frequently detected mutation and was dominant among strains isolated from children with peptic ulcer disease (80%). Mutations in the rdxA gene were found significantly more frequently among MET-resistant strains than MET-sensitive strains (p = 0.03, Chi2 = 4.3909). In children, a higher frequency of H. pylori multiresistant strains was observed compared with the previous study in the same area. Differences were found in the occurrence of point mutations among H. pylori strains resistant to CH isolated from children with different clinical diagnoses.

Eradication of Helicobacter pylori: the power of nanosized formulations

Nanomedicine ◽  
2020 ◽  
Vol 15 (5) ◽  
pp. 527-542
Author(s):  
Qianyu Zhang ◽  
Wen Wu ◽  
Jinqiang Zhang ◽  
Xuefeng Xia
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Peptic Ulcer ◽  
Gastric Carcinoma ◽  
Antibacterial Agents ◽  
Antimicrobial Agents ◽  
Mucosal Barrier ◽  
Harsh Environment ◽  
H Pylori ◽  
Cure Rates

Helicobacter pylori is a pathogen that is considered to cause several gastric disorders such as chronic gastritis, peptic ulcer and even gastric carcinoma. The current therapeutic regimens mainly constitute of a combination of several antimicrobial agents and proton pump inhibitors. However, the prevalence of antibiotic resistance has been significantly lowering the cure rates over the years. Nanocarriers possess unique strengths in this regard owing to the fact that they can protect the drugs (such as antibiotics) from the harsh environment in the stomach, penetrate the mucosal barrier and deliver drugs to the desired site. In this review we summarized recent studies of different antibacterial agents orally delivered by nanosized carriers for the eradication of H. pylori.

scholarly journals A Next-Generation Sequencing-Based Approach to Identify Genetic Determinants of Antibiotic Resistance in Cambodian Helicobacter pylori Clinical Isolates

2019 ◽  
Vol 8 (6) ◽  
pp. 858 ◽  
Author(s):  
Vo Phuoc Tuan ◽  
Dou Narith ◽  
Evariste Tshibangu-Kabamba ◽  
Ho Dang Quy Dung ◽  
Pham Thanh Viet ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Antibiotic Resistance ◽  
Genetic Resistance ◽  
23S Rrna ◽  
Next Generation ◽  
Genetic Determinants ◽  
Resistance Determinants ◽  
Genotypic Analysis ◽  
H Pylori ◽  
Resistant Genotypes

We evaluated the primary resistance of Helicobacter pylori (H. pylori) to routinely used antibiotics in Cambodia, an unexplored topic in the country, and assessed next-generation sequencing’s (NGS) potential to discover genetic resistance determinants. Fifty-five H. pylori strains were successfully cultured and screened for antibiotic susceptibility using agar dilution. Genotypic analysis was performed using NGS data with a CLC genomic workbench. PlasmidSeeker was used to detect plasmids. The correlation between resistant genotypes and phenotypes was evaluated statistically. Resistances to metronidazole (MTZ), levofloxacin (LVX), clarithromycin (CLR), and amoxicillin (AMX) were 96.4%, 67.3%, 25.5%, and 9.1%, respectively. No resistance to tetracycline (TET) was observed. Multi-drug resistance affected 76.4% of strains. No plasmids were found, but genetic determinants of resistance to CLR, LVX, and AMX were 23S rRNA (A2146G and A2147G), GyrA (N87K and D91Y/N/G), and pbp1 (P473L), respectively. No determinants were genetically linked to MTZ or TET resistance. There was high concordance between resistant genotypes and phenotypes for AMX, LVX, and CLR. We observed high antibiotic resistance rates of CLR, MTZ, and LVX, emphasizing the need for periodic evaluation and alternative therapies in Cambodia. NGS showed high capability for detecting genetic resistance determinants and potential for implementation in local treatment policies.

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