Serologic diagnosis of Helicobacter pylori in chidren and its utility – a prospective study

Abstract

Introduction. Helicobacter pylori, an ubiquitary spread bacterium, is one of the main ethiologic factors of gastritis and peptic ulcer in children. Several diagnostic methods of this infection have been developed, both invasive and noninvasive, with the purpose of promoting early identification of the bacterium, therefore preventing its associated complications. Serologic tests, based upon detection of circulating Helicobacter pylori antibodies, one of the first diagnostic tests used, are widely available, non-invasive, cost-efficient, but do not possess the sensibility and specificity of histology. Objectives. Through this study, we intend to identify the usefulness of IgA and IgG antibodies measurement in the diagnosis of Helicobacter pylori, by comparison with histhopathology examination. Nevertheless, we wish to establish wheteher there is a correlation between the presence of depictable antibodies and certain changes of the gastric mucosa. Material and methods. We conducted a retrospective study, which included 84 patients aged between 4 and 17 years, with chronic dyspeptic symptoms, who underwent an upper digestive endoscopy, accompanied by gastric biopsies. Serologic Helicobacter pylori tests were performed in each of these patients, their results being compared with the microscopic description of gastric mucosal tissue. Results. IgA and IgG antibodies had lower sensitivity (50% and 81.25%, respectively) and specificity (88.88% and 81.08%, respectively) than microscopic examination. Positivation of IgA antibodies, as an alone serologic response or in combination with depictable IgG antibodies was significantly corelated with chronic gastritis caused by Helicobacter pylori (p<0.001). Conclusions. Serologic tests have a lower diagnostic sensibility and specificity than histhology in the case of Helicobacter pylori, according to our study. Presence of this bacteria on microscopy was associated with chronic gastritis in all cases. Therefore, this study cannot provide enough data regarding the anatomopathological modifications associated with positive serum antibodies.

Keywords

• helicobacter pylori
• peptic ulcer
• children
• antibodies
• serologic diagnosis