[Helicobacter pylori: comparative study of different diagnostic techniques]

Abstract

Objective: To compare the different diagnostic techniques of Helicobacter Pylori infection, confronting the bacteriological culture to other faster, less expensive and easier techniques, such as the urease test, methylen blue and Gram stained smears, the histopathologic examination of biopsies specimens, and the detection of IgG antibodies anti Helicobacter Pylori.

Material and methods: 43 patients with gastroduodenal symptoms who had not taken NSAIDs and who presented endoscopic signs of inlammation and/or gastroduodenal ulcer were prospectively studied. Biopsies specimens of antrum, gastric fundus and duodenal bulb were taken and processed in the following way: methylen blue and Gram stained smears and Hematoxylin and eosin stained section. Studies were performed in to all the 43 patients. Urease test was performed in the antrum specimens of 37 patients, and inmunologic test by inmunoenzimatic technique (ELISA) in 40 of them.

Results: Methylen blue and Gram stained smears: sensitivity (S): 100% and specificity (E): 76% Histopathologic examination (S): 86% (E): 61%, urease test (S) 100% (E) 62.5%, antibodies anti H.P. not possible to calculate.

Discussion: The authors have taken the microbiological culture as a reference technique because the isolation and identification of the bacteria are the most important signs of its presence and vitality. Stained smears, histopathologic examination and the urease test are fast, inexpensive techniques with high sensitivity for diagnosis. However, the inmunologic test is reveals better to the prevalence of the infection.