[Diagnostic value of different methods applied for detecting Helicobacter pylori infection in gastric mucosa]

The aim of the paper comprised: 1) estimating the incidence of Helicobacter pylori (H. pylori) infection in subjects directed to undergo endoscopic examination due to ailments involving the upper segments of the alimentary tract, 2) determination of the degree of H. pylorii infection detectability on the basis of invasive methods (bacterial culture, urease test and histological examination of specimens stained by Giemsa method) and non-invasive (serological investigation, skin test) with endoscopic image and histopathologic changes in gastric mucosa being talken into consideration, 3) assessing the titer of class IgG anti-H. pylori antibodies in subjects with endoscopic and histopathologic changes of gastric mucosa, infected by H. pylori, as well as persons after eradication of bacteria, 4) estimating the diagnostic value of individual methods. The study material consisted of 428 patients (224 women and 204 men) investigated at Endoscopy Laboratory of Internal Diseases Clinic in the years 1991-1994. Bacterial cultures and urease tests were performed in all the studied subjects, 230 specimens stained by Giemsa method were examined histopathologically, in 351 subjects the titer of class IgG anti-H. pylori antibodies in blood serum were determined by ELISA method, while in 73 persons the skin test from the suspension of dead bacterial colonies was carried out. Histopathological examination of mucosal sections was accomplished in 396 studied subjects, assessing the histological type of mucosal inflammation in H. pylorii infected persons and in those having not been infected. The applicability of the respective diagnostic methods was examined by calculating the sensitivity and specificity of the given method, and taking into account the results of bacterial culture as the reference method. It is evident from the performed investigations that the majority of subjects, having been endoscopically studied because of ailments stemming from the upper segment of the alimentary tract, were infected by H. pylori (Tab. 1, 2, 3). H. pylori colonisation in gastric mucosa was often accompanied by pathological changes of the stomach and duodenum in the endoscopic and histopathologic images. In the routine clinical diagnostics the urease test, histological examination of specimens stained by Giemsa method as well as bacterial culture are valuable methods of detecting H. pylorii infection. With regard to medium and high values of the titer of antibodies IgG anti-H. pylori, the serological investigation as a non-invasive method displays a high compliance with positive results of invasive examinations (Tab. 5, Fig. 1, 2, 3). An early skin test may become a screening method for detecting H. pylori infection, after its methodical modification.