scholarly journals Helicobacter pylori eradication according to sequencing-based 23S ribosomal RNA point mutation associated with clarithromycin resistance

2019 ◽  
Author(s):  
Seung In Seo ◽  
Byoung Joo ◽  
Jin Gu Kang ◽  
Hyoung Su Kim ◽  
Myoung Kuk Jang ◽  
...  

Abstract Background Clarithromycin resistance in Helicobacter pylori (H. pylori) is associated with point mutations in the 23S ribosomal RNA (rRNA) gene. A sequencing-based method can detect more point mutations than a polymerase chain reaction (PCR)-based method. We investigated the point mutations in the 23S rRNA genes of patients infected with clarithromycin-resistant H. pylori and compared the H. pylori eradication rates based on the identified clinically significant point mutations. Methods A total of 431 adult patients with H. pylori infection were retrospectively recruited in Kangdong Sacred Heart Hospital in 2017 and 2018. Patients who did not have point mutations related to clarithromycin resistance and/or had clinically insignificant point mutations were treated with PAC (proton pump inhibitor, amoxicillin, clarithromycin) for 7 days, while patients with clinically significant point mutations were treated with PAM (proton pump inhibitor, amoxicillin, metronidazole) for 7 days. H. pylori eradication rates were compared between the two groups. Results Sequencing-based detection of point mutations identified four mutations that were considered clinically significant (A2142G, A2142C, A2143G, A2143C), while all the other mutations were considered clinically insignificant. The clarithromycin resistance rate was 21.3% in the overall group of patients. A2143G was the most clinically significant point mutation (84/431, 19.5%), while T2182C was the most clinically insignificant point mutation (283/431, 65.7%). The H. pylori eradication rate in the overall group of patients was 83.7%, and the 7-day PAM-treated clarithromycin-resistance group showed a significantly lower eradication rate than the 7-day PAC-treated nonresistance group [ITT; 55.4% (51/92) vs. 74.3% (252/339), P=0.001, PP; 66.2% (51/77) vs. 88.4% (252/285), P=0.0001]. Conclusions There were significantly lower eradication rates in the patients with clarithromycin-resistant H. pylori as identified by the sequencing of point mutations in the 23S rRNA gene when treated with PAM for 7 days. A future study comparing treatment regimens in clarithromycin-resistant H. pylori-infected patients may be necessary.

2019 ◽  
Vol 9 (1) ◽  
pp. 54 ◽  
Author(s):  
Seung In Seo ◽  
Byoung Joo Do ◽  
Jin Gu Kang ◽  
Hyoung Su Kim ◽  
Myoung Kuk Jang ◽  
...  

Background/Aims: Clarithromycin resistance in Helicobacter pylori is associated with point mutations in the 23S ribosomal RNA (rRNA) gene. We investigated the point mutations in the 23S rRNA genes of patients with clarithromycin-resistant H. pylori and compared the H. pylori eradication rates based on the point mutations. Methods: A total of 431 adult patients with H. pylori infection were recruited in Kangdong Sacred Heart Hospital in 2017 and 2018. Patients who did not have point mutations related to clarithromycin resistance and/or had clinically insignificant point mutations were treated with PAC (proton pump inhibitor, amoxicillin, clarithromycin) for seven days, while patients with clinically significant point mutations were treated with PAM (proton pump inhibitor, amoxicillin, metronidazole) for seven days. H. pylori eradication rates were compared. Results: Sequencing-based detection of point mutations identified four mutations that were considered clinically significant (A2142G, A2142C, A2143G, A2143C). The clarithromycin resistance rate was 21.3% in the overall group of patients. A2143G was the most clinically significant point mutation (84/431, 19.5%), while T2182C was the most clinically insignificant point mutation (283/431, 65.7%). The overall H. pylori eradication rate was 83.7%, and the seven-day PAM-treated clarithromycin-resistance group showed a significantly lower eradication rate than the seven-day PAC-treated nonresistance group (ITT; 55.4% (51/92) vs. 74.3% (252/339), p = 0.001, PP; 66.2% (51/77) vs. 88.4% (252/285), p = 0.0001). Conclusions: There were significantly lower eradication rates in the patients with clarithromycin-resistant H. pylori when treated with PAM for seven days. A future study comparing treatment regimens in clarithromycin-resistant H. pylori-infected patients may be necessary.


2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Jina Vazirzadeh ◽  
Jamal Falahi ◽  
Sharareh Moghim ◽  
Tahmineh Narimani ◽  
Rahmatollah Rafiei ◽  
...  

Background and Aims. Helicobacter pylori is a common infectious bacterium mostly found in gastroduodenal diseases. The increased prevalence of clarithromycin-resistant H. pylori strains is a major challenge in the successful treatment of infections caused by this organism. The present study is aimed at detecting the clarithromycin resistance pattern of H. pylori strains isolated from gastric biopsies and evaluating point mutations of the 23S rRNA gene. Patients and methods. In the present descriptive cross-sectional study, 165 patients with gastrointestinal disorders, who were referred to the Endoscopy Center of Dr. Shariati Hospital of Isfahan, Iran, were enrolled from April to July 2018. H. pylori infection was diagnosed by culture, and susceptibility of the isolates to clarithromycin was assessed by the E-test. Minimum inhibitory concentration (MIC) values were obtained based on EUCAST recommendations. Also, fluorescence in situ hybridization (FISH) was used to determine point mutations associated with clarithromycin resistance. Results. By using culturing, H. pylori was isolated from 50.3% (83/165) gastric biopsy specimens. The overall frequency of resistance to clarithromycin was 25.3% (21/83) by the E-test. In the resistance genotypic analysis, 19 isolates had mutations. The prevalence of A2143G and A2144G mutations was 68.4% (13/19) and 31.5% (6/19), respectively. A2143C mutation was not tracked in any isolate. Two isolates with MIC>0.5 μg/mL had no mutations that could be related to other mechanisms of resistance. Conclusion. As presented in the study, the high prevalence of clarithromycin-resistant H. pylori due to point mutations of the 23S rRNA gene indicates the necessity of revising the standard treatment regimen based on antibiotic susceptibility pattern of each region.


2014 ◽  
Vol 61 (2) ◽  
Author(s):  
Karolina Klesiewicz ◽  
Paweł Nowak ◽  
Elżbieta Karczewska ◽  
Iwona Skiba ◽  
Izabela Wojtas-Bonior ◽  
...  

The occurrence of clarithromycin resistance among Helicobacter pylori strains is a major cause of the treatment failure. Resistance to this drug is conferred by point mutations in 23S rRNA gene and the most prevalent mutations are A2143G and A2142G. The aim of the study was to evaluate the occurrence of A2143G and A2142G mutations in a group of H. pylori strains resistant to clarithromycin. The study included 21 clarithromycin-resistant H. pylori strains collected between 2006 and 2009 in southern Poland. Resistance to clarithromycin was quantitatively tested with the E-test to determine the minimal inhibitory concentration (MIC value). The point mutations of H. pylori isolates were detected by PCR followed by RFLP analysis. The MIC values for clarithromycin for the analyzed strains ranged from 1.5 mg/L to 64 mg/L. Nine H. pylori strains exhibited A2143G mutation and A2142G mutation was found in 9 isolates as well. The results of RFLP analysis of 3 clarithromycin-resistant strains were negative for both mutations. The average MIC values for A2143G and A2142G mutants were 6 and 30 mg/L, respectively. Frequencies of A2143G and A2142G mutations were the same in all isolates tested. Strains with A2143G mutation exhibited lower MIC values than A2142G mutants. Application of PCR-RFLP method for detection of clarithromycin resistance allows for better and more efficient management of H. pylori infections.


2020 ◽  
Author(s):  
Aalaa Mahgoub Albasha ◽  
Maram M. Alnosh ◽  
Esraa Hassan Osman ◽  
Duha M Zeinalabdin ◽  
Amira A M Fadl ◽  
...  

Abstract Background: Clarithromycin resistant Helicobacter pylori (H. pylori) strains represent a worldwide health problem. These stains are usually carrying mutations within the 23S rRNA gene associated with clarithromycin resistance. This study aimed to detect H. pylori and clarithromycin resistant associated mutations from Sudanese patients with gastritis symptoms.Materials and Methods: Two hundred and eighty-eight gastric biopsies were collected using gastrointestinal endoscopy from patients with gastritis symptoms in different hospitals in Khartoum state. H. pylori was detected by PCR using primers targeting 16S rRNA and 23S rRNA. Then allele-specific PCR and DNA sequencing were used to screen for the presence of A2142G and A2143G point mutations.Results: Out of 288 samples, H. pylori was detected in 97 (33.7%) sample. Allele-specific PCR detected the variant A2142G in 9/97 (9.3%) sample, while A2143G mutation was not found in any sample. The DNA sequencing revealed the presence of mutations associated with clarithromycin-resistance in 48% (12/25) of samples; the A2142G was present in one sample, A2143G in 5 samples, T2182C in 4 samples, and C2195T in 3 samples. There was no association of 23S rRNA gene point mutations with gender, age group and geographical distribution of patients.Conclusion: This study revealed a high frequency (48%) of mutations associated with clarithromycin resistance using DNA sequencing of the 23S rRNA gene's V domain. This information should be taken into consideration before choosing optimal therapy for H. pylori eradication.


2015 ◽  
pp. 54-61
Author(s):  
Ngoc Doanh Pham ◽  
Van Huy Tran ◽  
Thi Minh Thi Ha

Background: Clarithromycin resistance of H-pylori is the main cause leading to treatment failure. Aim: The purpose of this study was to determine the rate of clarithromycin resistance mutation on gene 23S ribosomal popular robonucleotide acid (rRNA) of H-pylori in patients with chronic gastritis in Quang Ngai General Hospital PCR-RFLP. Method: This is a cross-sectional study in 64 patients infected with H-pylori was determined by 3 methods and chronic gastritis proven by histology. Sample collection conducted in Quang Ngai general hospital and molecular biology tests were conducted in the medical genetics department Hue of Medical and Pharmaceutical University. Urease test, histopathological examination and perform HE staining PCR 23S rRNA gene fragment of H-pylori to determine H-pylori infection. Analysis of genetic mutations in the 23S rRNA point is performed by PCR-RFLP technique. Results: Of the 64 biopsies qualify included in the study, 41 samples with clarithromycin resistance point mutations (64%), of which 40 (62.5%) had mutations A2143A, one sample with A2142A (2%). No samples had mutations A2142C and no more than one mutation.Conclusion: This is the first time we report mutations related to clarithromycin of H-pylori in Quang Ngai province. Mutations rate is high (64%), among the common mutations, the most common mutantation is A2143G. Key words: Helicobacter pylori, clarithromycin resistance, PCR-RFLP, point mutations


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Aalaa Mahgoub Albasha ◽  
Maram M. Elnosh ◽  
Esraa Hassan Osman ◽  
Duha M. Zeinalabdin ◽  
Amira A. M. Fadl ◽  
...  

Abstract Background Clarithromycin resistant Helicobacter pylori (H. pylori) strains represent a worldwide health problem. These stains are usually carrying mutations within the 23S rRNA gene associated with clarithromycin resistance. This study aimed to detect H. pylori and clarithromycin resistant associated mutations from Sudanese patients with gastritis symptoms. Materials and methods Two hundred and eighty-eight gastric biopsies were collected using gastrointestinal endoscopy from patients with gastritis symptoms in different hospitals in Khartoum state. H. pylori was detected by PCR using primer targeting 16S rRNA. Then allele-specific PCR and DNA sequencing were used to screen for the presence of A2142G and A2143G point mutations. Results Out of 288 samples, H. pylori was detected in 88 (~ 30.6%) samples by 16 s RNA. Allele-specific PCR detected the variant A2142G in 9/53 (~ 17%) sample, while A2143G mutation was not found in any sample. The DNA sequencing revealed the presence of mutations associated with clarithromycin-resistance in 36% (9/25) of samples; the A2142G was present in one sample, A2143G in 5 samples and T2182C in 4 samples. Additionally, another point mutation (C2195T) was detected in 3 samples. There was no association of 23S rRNA gene point mutations with gender, age group, and patients’ geographical distribution. Conclusion This study revealed a high frequency (36%) of mutations associated with clarithromycin resistance using DNA sequencing of the 23S rRNA gene’s V domain. This information should be taken into consideration to avoid eradication therapy failing.


2016 ◽  
pp. 12-20
Author(s):  
Thi Minh Thi Ha ◽  
Van Huy Tran ◽  
Viet Nhan Nguyen ◽  
Thanh Hoa Nguyen ◽  
Phan Tuong Quynh Le

Background: Clarithromycin resistance in Helicobacter pylori has been found to be associated with point mutations at positions 2142 and 2143 in 23SrRNA gene. The aims of this study were: (1) to determine the rates of point mutations A2143G, A2142G and A2142C in 23SrRNA gene of H. pylori among patients with chronic gastritis by PCR-RFLP technique; and (2) to assessthe association between these mutations and some clinical, endoscopic and histopathological characteristics of chronic gastritis. Patients and methods: two hundreds and twenty six patients with H. pylori-positive chronic gastritis were determined A2143G, A2142G and A2142C mutations by PCR-RFLP technique with DNA extracted from endoscopic biopsy specimens of gastric mucosa. Results: The rate of point mutations at positions 2142 and 2143 in 23S rRNA gene of H. pylori was 35.4% in total, the A2143G and A2142G mutationsaccounted for 92.5% and 7.5% of all point mutations, respectively. No A2142C mutation was found. These mutations were not associated with age, gender,distribution of gastritis, and the presence of atrophic gastritis. The rate of A2143G mutation in groups with and without a history of clarithromycin treatment were 44.9% and 24.8%, respectively (p = 0,0065). The A2142G mutation was associated with intestinal metaplasia and/or dysplasia. Conclusion: The point mutations at positions 2142 and 2143 in 23S rRNA gene were found at a high rate in H. pylori strains amongpatients with chronic gastritis, with the absolute predominance of A2143G mutation. The A2143G mutation was associated with a history of clarithromycin treatment. Key words: 23S rRNA gene, Helicobacter pylori, A2143G, A2142G, A2142C mutation, clarithromycin resistance, chronic gastritis.


2017 ◽  
Vol 61 (4) ◽  
Author(s):  
Derrick Chen ◽  
Scott A. Cunningham ◽  
Nicolynn C. Cole ◽  
Peggy C. Kohner ◽  
Jayawant N. Mandrekar ◽  
...  

ABSTRACT Failure to eradicate Helicobacter pylori infection is often a result of antimicrobial resistance, which for clarithromycin is typically mediated by specific point mutations in the 23S rRNA gene. The purpose of this study was to define current patterns of antimicrobial susceptibility in H. pylori isolates derived primarily from the United States and to survey them for the presence of point mutations in the 23S rRNA gene and assess the ability of these mutations to predict phenotypic clarithromycin susceptibility. Antimicrobial susceptibility testing was performed using agar dilution on 413 H. pylori isolates submitted to Mayo Medical Laboratories for susceptibility testing. For a subset of these isolates, a 150-bp segment of the 23S rRNA gene was sequenced. A total of 1,970 MICs were reported over the 4-year study period. The rate of clarithromycin resistance was high (70.4%), and elevated MICs were frequently observed for metronidazole (82.4% of isolates had an MIC of >8 μg/ml) and ciprofloxacin (53.5% of isolates had an MIC of >1 μg/ml). A total of 111 archived H. pylori isolates underwent 23S rRNA gene sequencing; we found 95% concordance between genotypes and phenotypes (P = 0.9802). Resistance to clarithromycin was most commonly due to an A2143G mutation (82%), followed by A2142G (14%) and A2142C (4%) mutations. Clinical H. pylori isolates derived primarily from the United States demonstrated a high rate of clarithromycin resistance and elevated metronidazole and ciprofloxacin MICs. The relative distribution of point mutations at positions 2143 and 2142 in the 23S rRNA gene in clarithromycin-resistant H. pylori was similar to that reported from other parts of the world; these mutations predict phenotypic resistance to clarithromycin.


1998 ◽  
Vol 42 (8) ◽  
pp. 1952-1958 ◽  
Author(s):  
Ge Wang ◽  
Diane E. Taylor

ABSTRACT Clarithromycin resistance in Helicobacter pylori is mainly due to A-to-G mutations within the peptidyltransferase region of the 23S rRNA. In the present study, cross-resistance to macrolide, lincosamide, and streptogramin B (MLS) antibiotics (MLS phenotypes) has been investigated for several clinical isolates of H. pylori. Two major types of MLS resistance were identified and correlated with specific point mutations in the 23S rRNA gene. The A2142G mutation was linked with high-level cross-resistance to all MLS antibiotics (type I), and the A2143G mutation gave rise to an intermediate level of resistance to clarithromycin and clindamycin but no resistance to streptogramin B (type II). In addition, streptogramin A and streptogramin B were demonstrated to have a synergistic effect on both MLS-sensitive and MLS-resistant H. pyloristrains. To further understand the mechanism of MLS resistance inH. pylori, we performed in vitro site-directed mutagenesis (substitution of G, C, or T for A at either position 2142 or 2143 of the 23S rRNA gene). The site-directed point mutations were introduced into a clarithromycin-susceptible strain, H. pylori UA802, by natural transformation followed by characterization of their effects on MLS resistance in an isogenic background. Strains with A-to-G and A-to-C mutations at the same position within the 23S rRNA gene had similar levels of clarithromycin resistance, and this level of resistance was higher than that for strains with the A-to-T mutation. Mutations at position 2142 conferred a higher level of clarithromycin resistance than mutations at position 2143. All mutations at position 2142 conferred cross-resistance to all MLS antibiotics, which corresponds to the type I MLS phenotype, whereas mutations at position 2143 were associated with a type II MLS phenotype with no resistance to streptogramin B. To explain that A-to-G transitions were predominantly observed in clarithromycin-resistant clinical isolates, we propose a possible mechanism by which A-to-G mutations are preferentially produced in H. pylori.


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