STUDY OF DIAGNOSTIC TESTS FOR HELICOBACTER PYLORI INFECTION

Helicobacter pylori is the causative agent of most cases of gastritis and peptic ulcer. The diagnosis of H. pylori is an essential element in the management of many common gastrointestinal pathologies. AIMS 1. Comparison of invasive and non-invasive tests to choose the appropriate test for the diagnosis of H. pylori infection. 2. Validation of the comparison of the different diagnostic tests. METHOD Blood and antral biopsy specimens from 100 acid peptic disease patients and blood samples from 10 control subjects were collected. Biopsies were used for Rapid Urease Test (RUT), culture and Gram's stain by conventional method. Serology using Euroimmun Anti Helicobacter pylori IgG ELISA was done. The efficacy of these tests was determined by calculating the sensitivity, specificity, positive predictive value, negative predictive value and accuracy using culture as gold standard. RESULTS Of the 100 cases 14% were culture positive, 18% Gram stain positive, 36% Rapid urease test positive and 42% were positive for Serology IgG antibodies for H. pylori. Maximum percentage of positivity was in peptic ulcer cases (52.9%) followed by Gastritis cases (23.6%) and Dyspepsia cases (14.2%). Among the 100 cases of study group, 42(42%) were positive by serological test IgG ELISA for H. pylori, whereas 3(30%) were positive out of 10 in control group. RUT, IgG Serology showed 100% sensitivity and negative predictive value and Gram stain showed highest specificity (90.1%). CONCLUSION RUT+Gram's stain+IgG Serology showed highest Sensitivity, Specificity, Positive predictive value, Negative predictive value and Accuracy. IgG Serology indicates a marker for infection. It can be used as a primary diagnostic procedure.