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Observational Study
. 2016 Sep 7;22(33):7587-94.
doi: 10.3748/wjg.v22.i33.7587.

Detection of Helicobacter pylori resistance to clarithromycin and fluoroquinolones in Brazil: A national survey

Bruno Squarcio Sanches  1 , Gustavo Miranda Martins  1 , Karine Lima  1 , Bianca Cota  1 , Luciana Dias Moretzsohn  1 , Laercio Tenorio Ribeiro  1 , Helenice P Breyer  1 , Ismael Maguilnik  1 , Aline Bessa Maia  1 , Joffre Rezende-Filho  1 , Ana Carolina Meira  1 , Henrique Pinto  1 , Edson Alves  1 , Ramiro Mascarenhas  1 , Raissa Passos  1 , Julia Duarte de Souza  1 , Osmar Reni Trindade  1 , Luiz Gonzaga Coelho  1
Affiliations
Observational Study

Detection of Helicobacter pylori resistance to clarithromycin and fluoroquinolones in Brazil: A national survey

Bruno Squarcio Sanches et al. World J Gastroenterol. .

Abstract

Aim: To evaluate bacterial resistance to clarithromycin and fluoroquinolones in Brazil using molecular methods.

Methods: The primary antibiotic resistance rates of Helicobacter pylori (H. pylori) were determined from November 2012 to March 2015 in the Southern, South-Eastern, Northern, North-Eastern, and Central-Western regions of Brazil. Four hundred ninety H. pylori patients [66% female, mean age 43 years (range: 18-79)] who had never been previously treated for this infection were enrolled. All patients underwent gastroscopy with antrum and corpus biopsies and molecular testing using GenoType HelicoDR (Hain Life Science, Germany). This test was performed to detect the presence of H. pylori and to identify point mutations in the genes responsible for clarithromycin and fluoroquinolone resistance. The molecular procedure was divided into three steps: DNA extraction from the biopsies, multiplex amplification, and reverse hybridization.

Results: Clarithromycin resistance was found in 83 (16.9%) patients, and fluoroquinolone resistance was found in 66 (13.5%) patients. There was no statistical difference in resistance to either clarithromycin or fluoroquinolones (P = 0.55 and P = 0.06, respectively) among the different regions of Brazil. Dual resistance to clarithromycin and fluoroquinolones was found in 4.3% (21/490) of patients. The A2147G mutation was present in 90.4% (75/83), A2146G in 16.9% (14/83) and A2146C in 3.6% (3/83) of clarithromycin-resistant patients. In 10.8% (9/83) of clarithromycin-resistant samples, more than 01 mutation in the 23S rRNA gene was noticed. In fluoroquinolone-resistant samples, 37.9% (25/66) showed mutations not specified by the GenoType HelicoDR test. D91N mutation was observed in 34.8% (23/66), D91G in 18.1% (12/66), N87K in 16.6% (11/66) and D91Y in 13.6% (9/66) of cases. Among fluoroquinolone-resistant samples, 37.9% (25/66) showed mutations not specified by the GenoType HelicoDR test.

Conclusion: The H. pylori clarithromycin resistance rate in Brazil is at the borderline (15%-20%) for applying the standard triple therapy. The fluoroquinolone resistance rate (13.5%) is equally concerning.

Keywords: Clarithromycin; Fluoroquinolones; Helicobacter pylori; Microbial drug resistance; Molecular diagnostic techniques.

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Conflict of interest statement

Conflict-of-interest statement: The authors have no conflict of interest to declare.

References

    1. Chey WD, Wong BC. American College of Gastroenterology guideline on the management of Helicobacter pylori infection. Am J Gastroenterol. 2007;102:1808–1825. - PubMed
    1. Malfertheiner P, Megraud F, O’Morain C, Bazzoli F, El-Omar E, Graham D, Hunt R, Rokkas T, Vakil N, Kuipers EJ. Current concepts in the management of Helicobacter pylori infection: the Maastricht III Consensus Report. Gut. 2007;56:772–781. - PMC - PubMed
    1. Coelho LG, Maguinilk I, Zaterka S, Parente JM, do Carmo Friche Passos M, Moraes-Filho JP. 3rd Brazilian Consensus on Helicobacter pylori. Arq Gastroenterol. 2013;50 - PubMed
    1. Malfertheiner P, Megraud F, O’Morain CA, Atherton J, Axon AT, Bazzoli F, Gensini GF, Gisbert JP, Graham DY, Rokkas T, et al. Management of Helicobacter pylori infection--the Maastricht IV/ Florence Consensus Report. Gut. 2012;61:646–664. - PubMed
    1. Fock KM, Katelaris P, Sugano K, Ang TL, Hunt R, Talley NJ, Lam SK, Xiao SD, Tan HJ, Wu CY, et al. Second Asia-Pacific Consensus Guidelines for Helicobacter pylori infection. J Gastroenterol Hepatol. 2009;24:1587–1600. - PubMed

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