Prevalence of clarithromycin resistance in Helicobacter pylori in Santiago, Chile, estimated by real-time PCR directly from gastric mucosa.
BMC Gastroenterol
; 18(1): 91, 2018 Jun 20.
Article
em En
| MEDLINE
| ID: mdl-29925321
BACKGROUND: Current available treatments for Helicobacter pylori eradication are chosen according to local clarithromycin and metronidazole resistance prevalence. The aim of this study was to estimate, by means of molecular methods, both clarithromycin and metronidazole resistance in gastric mucosa from patients infected with H.pylori. METHODS: A total of 191 DNA samples were analyzed. DNA was purified from gastric mucosa obtained from patients who underwent an upper gastrointestinal endoscopy at an university hospital from Santiago, Chile, between 2011 and 2014. H.pylori was detected by real-time PCR. A 5'exonuclease assay was developed to detect A2142G and A2143G mutations among H.pylori-positive samples. rdxA gene was sequenced in samples harboring A2142G and A2143G mutations in order to detect mutations that potentially confer dual clarithromycin and metronidazole resistance. RESULTS: Ninety-three (93) out of 191 DNA samples obtained from gastric mucosa were H.pylori-positive (48.7%). Clarithromycin-resistance was detected in 29 samples (31.2% [95%CI 22.0-41.6%]). The sequencing of rdxA gene revealed that two samples harbored truncating mutations in rdxA, one sample had an in-frame deletion, and 11 had amino acid changes that likely cause metronidazole resistance. CONCLUSIONS: We estimated a prevalence of clarithomycin-resistance of 31.8% in Santiago, Chile. Three of them harbor inactivating mutations in rdxA and 11 had missense mutations likely conferring metronidazole resistance. Our results require further confirmation. Nevertheless, they are significant as an initial approximation in re-evaluating the guidelines for H.pylori eradication currently used in Chile.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Helicobacter pylori
/
Infecções por Helicobacter
/
Claritromicina
/
Reação em Cadeia da Polimerase em Tempo Real
/
Mucosa Gástrica
/
Antibacterianos
Tipo de estudo:
Guideline
/
Prevalence_studies
/
Risk_factors_studies
Limite:
Humans
País/Região como assunto:
America do sul
/
Chile
Idioma:
En
Revista:
BMC Gastroenterol
Assunto da revista:
GASTROENTEROLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Chile
País de publicação:
Reino Unido