[Efficacy of stool antigen and serologic tests in the diagnosis of Helicobacter pylori in Ecuadorian population].

Objective: To assess the effectiveness in the Ecuadorian population of 2 non-invasive methods for the detection of the Helicobacter pylori: the stool antigens immunoassay (HpSAg) and the determination IgG serum of'antibodies.
Materials and Methods: Eighty six dyspeptic patients were evaluated. In each, Helicobacter pylori presence was investigated with three methods: histology, HpSAg and serology. Sensibility and specificity values were obtained, as well as the positive and negative predictive values.
Results: The prevalence of Helicobacter pylori with the 3 tests was 89.53%. The sensibility, specificity, positive predictive value, and negative predictive value were: 42.5%, 69.2%, 88.6% and 17.6% with histology; 69.2%, 42.9%, 78.9% and 31% with HpSAg; 64.2%, 47.7%, 81.1% and 27.3% with serology.
Conclusions: In the highly prevalent Ecuadorian setting, HpSAg and serology have relative low sensibility and specificity values. Based on our results, it is necessary to assess for conditions that could alter their results, and strategies to increase the sensibility of these tests, including the histology.