Estudo soroepidemiológico da bactéria Helicobacter pylori em populações ribeirinhas amazônicas e a validação de um ensaio copromolecular para determinação da infecção

Abstract

The Amazonian riverine communities seem to have all of the conditions of sanitation and socioeconomic suspicions for the conditioning to the infection for Helicobacter pylori, bacterium associated to the etiopatogenia of several diseases gastrointestinais. In Brazil, they are registered on average, fifteen thousand cases of cancer of the digestive system a year, with a percentile adult in the north area. Once the H. pylori is considered one of the etiological agents of this malignitude, the objective of this study was to determine the prevalence of the infection for H. pylori and to accomplish the rising of epidemic variables and of susceptibility related to the bacterial infection in riverine communities, and to validate a rehearsal copromolecular for diagnosis of the infection. The accomplished study was of the type traverse, contemporary, analytical and observacional, understanding a sample of 200 individuals, of which they were collected blood, saliva and feces, besides the application of a questionnaire epidemic employee, with subjects driven to his/her identification, obtaining data on the conditions socioeconomic, hygienic, sanitary and symptoms. For detection sorologic of antibodies of the type IgG anti-H. pylori were used plasma samples that were tested for systemic antibodies of the type IgG anti-H. pylori through a rehearsal immunological, using the Kit Ridascreen Helicobacter IgG (RBiopharm AG, Germany); for detection it activates of the H. pylori, it was used the samples of feces that were tested through the Kit MKBIO H. pylori (MK BIO GMBH, DIMA, Germany). Besides the detection of antibodies and antigens for H. pylori, they were also applied techniques of molecular biology, in the fecal samples, to confirm the diagnosis of the infection, for direct detection of bacterial DNA, using the primers RNAr16S that amplify a fragment gene of 1200bp of the gender Helicobacter and the primers p1 and p2, which amplify a fragment gênico of 298 pb that codifies a protein antigenic of 26kDa species specify of the H. pylori. This research had about central point to the infection for the bacterium H. pylori, that was detected through three diagnosis methods: The sorologia, fecal antigen and PCR. The sorologia went to the chosen technique to relate with the epidemic aspects regarding the study, and the obtained results revealed a frequency of soropositive of 83,5% (167/200). The analysis of the epidemic variables related to the bacterial infection demonstrated a larger frequency of infected individuals female, in the age group from 0 to 17 years, in addition 97,4% of the population that ingested water without treatment were positive the infection. The comparison of the prevalence of the infection, obtained through the three different detection methods, they were high, however the detection copromolecular was what detected a smaller number of positive individuals (113/200), although it presents the largest indexes of sensibility 79% and specificities 100%. The detection copromolecular demonstrated to be an important tool in the detection of the bacterial infection, making possible in these populations the application of a test high sensibility and specificity, could be applied in the precocious detection of the patogen.