EVALUATION OF CLINICAL AND HOME PERFORMANCE OF THE C-13-UREA BREATH TEST FOR THE DETECTION OF HELICOBACTER-PYLORI

Objective: This study analyses the C-13-urea breath test with the aim of determining the optimal time interval between dosing and breath sam pling and examines the feasibility of having patients perform the test without supervision at home. Design: Prospective study comparing the C-13-urea breath test with four antral biopsy-based tests in a random population undergoing upper gastrointestinal endoscopy. Setting: One u niversity hospital and one general hospital. Patients: One hundred and four patients were included; 61 were Helicobacter pylori-positive and 43 H. pylori-negative according to biopsy-based tests. Interventions: The C-13-urea breath test was performed at home by collecting a basel ine and two post-dosing samples; the next day it was performed clinica lly by collecting a baseline and six post-dosing samples. A 100 mg dos e of C-13-urea and a test meal were used. Outcome measures: The breath samples collected were analysed. Excess delta (CO2)-C-13/(CO2)-C-12 v alues above five per million were considered positive. Results: The sp ecificity of the clinical test was 100% whereas that of the home-based test was 95.1%. The sensitivity of the clinical test depended on the time interval between dosing and collection of the evaluated sample. S ensitivity was 100% if the sample was taken 50 min or more after dosin g. The home-based test had a sensitivity of 94.8%. Conclusion: To obta in maximum sensitivity (100%) using the single-sample technique the sa mple has to be collected at least 50 min after dosing. It is feasible to have the test performed at home. Patient selection and thorough ins truction are necessary.