title: Low prevalence of clarithromycin-resistant Helicobacter pylori isolates with A2143G point mutation in the 23S rRNA gene in North India.
abstract: Resistance of Helicobacter pylori to clarithromycin is associated with a single base substitution in the 23S rRNA gene. In this study, clarithromycin-resistant H. pylori isolates were analysed for the presence of 23S rRNA gene mutations. H. pylori were isolated from 68 patients suffering from various gastroduodenal diseases in North India. Minimum inhibitory concentrations (MICs) were determined by the agar dilution method, and point mutations in clarithromycin-resistant strains were identified by PCR-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. Clarithromycin resistance was observed in 11.8% (8/68) of the H. pylori isolates in North India. The A2143G point mutation in the 23S rRNA gene was found in 87.5% (7/8) of the clarithromycin-resistant strains, and the A2142G mutation in association with the T2182C mutation was found in 12.5% (1/8). In conclusion, the continued high prevalence of clarithromycin-sensitive H. pylori strains (88.2%) observed in this study allows the use of the triple-therapy regimen for the treatment of H. pylori infection in this region. Surveillance studies need to be conducted at regular intervals for clarithromycin resistance in the population. To our knowledge, this is the first study in India to report that point mutations at position A2143G and at A2142G in association with T2182C are associated with clarithromycin resistance, confirming reports from other parts of the world.
authors.affiliation: Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India.
authors.forename: Valentina
authors.initials: V
authors.lastname: Gehlot
authors.affiliation: Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India.
authors.forename: Shweta
authors.initials: S
authors.lastname: Mahant
authors.affiliation: National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India.
authors.forename: Asish Kumar
authors.initials: AK
authors.lastname: Mukhopadhyay
authors.affiliation: Yashoda Superspecialty Hospital, Ghaziabad, Uttar Pradesh, India; Max Superspecialty Hospital, Vaishali, Ghaziabad, NCR, India.
authors.forename: Kunal
authors.initials: K
authors.lastname: Das
authors.affiliation: National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India.
authors.forename: Jawed
authors.initials: J
authors.lastname: Alam
authors.affiliation: National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India.
authors.forename: Prachetash
authors.initials: P
authors.lastname: Ghosh
authors.affiliation: Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh, India. Electronic address: rajashreepatra79@yahoo.co.in.
authors.forename: Rajashree
authors.initials: R
authors.lastname: Das
mesh_terms: D000900:Anti-Bacterial Agents; D017291:Clarithromycin; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000235:genetics*; D006801:Humans; D007194:India; D017354:Point Mutation; D015995:Prevalence; D012338:RNA, Ribosomal, 23S / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D012338:RNA, Ribosomal, 23S; D017291:Clarithromycin
keywords: 23S rRNA; Clarithromycin; Helicobacter pylori; Mutation; PCR-RFLP