Aplicações da biologia molecular no diagnóstico de Helicobacter pylori: revisão da literatura

Abstract

Helicobacter pylori (H. pylori) is a gram-negative bacterium which affects approximately 90% of the population worldwide and it has a higher prevalence in developing countries. This bacterium is responsible for causing diseases in the human stomach such as gastritis, ulcers and gastric adenocarcinoma. Currently we highlight the diagnostic methods using technologies of molecular biology such as PCR (Polymerase Chain Reaction) and fluorescence in situ hybridization (FISH). The conventional PCR diagnosis, as well as its variants, is the amplification of a specific DNA sequence of a bacterium. On the other hand, the FISH technique is based on hybridization of specific rRNA sequences of a bacterium with DNA probes marked with fluorescence. The molecular techniques are used on H. pylori infection diagnosis because they are the most sensitive, specific and rapid methods and they also allow virulence and drug resistence analysis. Thus, this article aims to highlight the application of molecular biology focusing in PCR, since the use of this tool enables faster, simple and effective diagnosis. The study deals with a descriptive literature review. The research was conducted in scientific databases using as main descriptors: H. pylori; molecular tools; diagnosis. It was observed a gradual approval of the use of molecular tools for the detection and characterization of H. pylori, determining a new phase for the laboratory diagnosis of this micro-organism.