Clarithromycin-resistant H. pylori primary strains and virulence genotypes in the Northeastern region of Brazil

• Autor(a) principal: Benigno, Tiago Gomes da Silva
• Data de Publicação: 2022
• Outros Autores: Ribeiro Junior, Howard Lopes, Azevedo, Orleâncio Gomes Ripardo de, Pinheiro, Ronald Feitosa, Oliveira, Roberta Taiane Germano de, Maciel, Felipe Silva, Oliveira, Edson Luiz de, Queiroz, Dulciene Maria Magalhães, Braga, Lucia Libanez Bessa Campelo
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista do Instituto de Medicina Tropical de São Paulo
• Texto Completo: https://www.revistas.usp.br/rimtsp/article/view/200086
• topic: H. pylori; Virulence factors; Clarithromycin-resistance

The increase of H. pylori resistance to clarithromycin is a concern. This study evaluated the prevalence of H. pylori’s primary resistance to clarithromycin and its association with virulence factors in adult dyspeptic patients and asymptomatic children. The gastric mucosa from patients (153 gastritis, 24 gastric cancer, 21 peptic ulcer) and gastric juice obtained by string test from 24 H. pylori and 23S rRNA positive asymptomatic children were included. The clarithromycin resistance was assessed by TaqMan RT-PCR 23S rRNA point mutations, A2142G and/or A2143G, and H. pylori virulence markers by PCR. Overall, the clarithromycin resistance was 14.4% (32/222), 14.2% in adults, and 12% in children, whereas origin, gender, and disease were not distinctive factors. The most prevalent point mutation was A2143G (62.5%). The point mutation was significantly less frequent in cagA-positive (11.4%) than in cagA-negative (23.6%) strains (p=0.03 OR = 0.4 95%CI = 0.19 - 0.91) as well as in cagE-positive (10.2%), cagE-negative (21.2%) (p=0.03 OR: 0.4 I.C:0.20-0.91). No difference was found in iceA or vacA alleles genotypes. Primary resistance to clarithromycin was lower than that reported in Southeast Brazil. The cagA and cagE positive H. pylori samples have few point mutations suggesting that individuals infected with virulent strains may be more susceptible to anti-H. pylori treatment.