Dados do Trabalho

Título

Detection of the domain V of Helicobacter pylori 23S rRNA fraction in saliva collected on dry cotton

Introdução

Introduction. Helicobacter pylori is a bacterium that can cause chronic infection in humans, being a risk factor for the development of gastric cancer. In the Northern region of Brazil, Acre is one of the states with a high prevalence of gastric cancer, however, its etiology and risk factors are unknown. Currently, the gold standard test for diagnosing H. pylori is endoscopy with biopsy to detect the bacterium using the urease test. Endoscopy is an invasive exam that requires patient sedation, so when it is necessary to monitor the treatment of H. pylori infection, alternative, and less invasive methods would be a good option for the patient.    

Objetivo (s)

Objective. To detect nucleic acid of H. pylori in the saliva of individuals, attended at a gastroenterology clinic in Acre, in the Cruzeiro do Sul city, from July to November 2023.  

Material e Métodos

Material and methods. 175 saliva samples were collected from patients treated at the gastroenterology clinic and who agreed to participate in the study by signing the informed consent form. The samples were collected on dry cotton and used for nucleic acid extraction using a Trizol-type reagent. The molecular diagnosis of H. pylori was carried out by PCR with oligonucleotides that amplify a 760 bp fragment corresponding to the gene that encodes the 23S fraction of the bacteria's 23S rRNA fraction.   

Resultados e Conclusão

Results: 123 samples from individuals with gastric symptoms from the Cruzeiro do Sul and nearby cities, in Acre, were positive for H. pylori. Positive results were distributed throughout the collection time and in the different cities of patients' origin.  Conclusion: The detection of H pylori DNA by PCR in saliva collected on dry cotton was successfully performed. The molecular marker used, a 760 bp fragment corresponding to the V domain of the 23S fraction of H. pylori rRNA, allows us to investigate the presence of mutations that confer resistance to treatment of the infection with macrolide antibiotics.  

Palavras Chave

Keywords: Helicobacter pylori; gastrointestinal alterations; COVID-19; RTqPCR