Molecular Detection of Antibiotic Resistance in South African Isolates of Helicobacter pylori

Gastroenterol Res Pract. 2013:2013:259457. doi: 10.1155/2013/259457. Epub 2013 Apr 24.

Abstract

Rapid diagnosis and treatment of Helicobacter pylori (H. pylori) presents a challenge. We aimed at investigating the presence of H. pylori, susceptibility profile, and associated mutations in an effort to validate the effectiveness of GenoType HelicoDR assay in H. pylori typing in our environment. Two hundred and fifty-four biopsy specimens were cultured and DNA extracted from seventy-eight positive cultures using the Qiagen DNA extraction kit. The GenoType Helico DR which employs reverse hybridisation was used to confirm the presence of H. pylori, determination of its susceptibility to antimicrobials, and detection of mutations conferring resistance to clarithromycin and fluoroquinolones. The organism was isolated from 168/254 (66.1 %) of the specimens by culture. Of the 78 strains used for further investigation, 12/78 (15.38%) were resistant to clarithromycin while 66/78 (84.61%) were susceptible. For fluoroquinolone, 70/78 (89.74%) strains were susceptible while 8 (10.26%) were resistant. Mutations were observed in 17 strains with A2147G being the most prevalent; A2146C and D91N were the least. The reverse hybridisation assay is an easy and fast technique in confirming the presence of H. pylori, its antimicrobial profile, and associated mutations. Analysis regarding the suitability of this assay for H. pylori typing is warranted in other regions.