7 research outputs found
A timeâsavingâmodified Giemsa stain is a better diagnostic method of Helicobacter pylori
Tripleânanostructuringâbased noninvasive electroâimmune sensing of CagA toxin for Helicobacter pylori
Comparative Evaluation of RUT, PCR and ELISA Tests for Detection of Infection with Cytotoxigenic H. pylori
Purpose: Helicobacter
pylori is one of the most prevalent infectious agents
in the world which causes a variety of gastrointestinal diseases including
gastritis, peptic ulcer and gastric carcinoma. The objective of this study was
to comparatively evaluate invasive (rapid urease test and polymerase chain
reaction) and non-invasive (enzyme-linked immunosorbent assay) tests in
diagnosis of infection with cytotoxigenic H. pylori.
Methods: Biopsy specimens and sera were collected from
105 patients with gastric disorders. The presence of H. pylori infection
in gastric biopsies was evaluated by RUT and PCR methods using chemotaxis
signal transduction protein gene (CSTP), Urea C and HP-16srRNA primers. Serum
samples were used for the ELISA test. Detection of infection with cag
A-positive strains was performed by PCR and cag A-IgG ELISA kit.
Results: Patients with at least two out of three
positive results were regarded as infected. The sensitivity, specificity,
predictive value and accuracy of the three different methods were evaluated. Of
the 105 gastric biopsies, H. pylori were positive in 51 patients
(48.57%). The best sensitivity (92.16%) belonged to RUT. The sensitivities of
other tests including PCR and ELISA test were 88.24% and 90.20%, respectively.
PCR showed the best specificity (94.44%), and the specificities of the other
tests including RUT and ELISA test, were 90.74 % and 61.11%, respectively.
Furthermore, results of PCR and cag A-IgG ELISA showed high prevalence of cag
A-positive strain in the study population.
Conclusion: Based on
our findings, serum ELISA is a rapid noninvasive test for screening of H.
pylori infection in the absence of endoscopy indication. In addition,
considering the high prevalence of cytotoxigenic H. pylori strains, cag
A is suggested as a promising target for PCR and non- invasive ELISA tests for
detection of infection with toxigenic strains