A simplified urea breath test for the diagnosis of Helicobacter pylori infection using the LARA System. Laser Assisted Ratio Analyzer

Abstract

Helicobacter pylori, one of the most prevalent human pathogens, is associated with chronic gastritis, peptic ulcer disease, and possibly gastric cancer and primary gastric lymphoma. The need to treat these patients has necessitated the development of improved methods to diagnose H. pylori infection. We present the preliminary assessment of a 13C-urea breath test (UBT) in which the expired 13CO2 is detected in a rapid, simple, inexpensive way by the LARA (Laser Assisted Ratio Analyzer) System (Alimenterics, Inc., Morris Plains, NJ). Eighty-seven consecutive patients, examined for upper gastrointestinal symptoms, underwent endoscopy. H. pylori infection was established by antral biopsies and a rapid urease test (CLOtest). The UBT was performed between 2 and 24 hours after endoscopy. Of the 84 analyzable patients, 70 were found to be H. pylori-positive either by histology or by CLOtest. All 70 were positive by the LARA UBT, yielding a sensitivity of 100%. Fourteen patients were negative for H. pylori by histology and the CLOtest. Of these, 12 were negative by the LARA UBT and 2 were positive, yielding a specificity of 85.7%; because of the limitations of H. pylori detection by histology or urease assays, however, the specificity of the UBT may have been underestimated. Our study demonstrates the feasibility of a nonradioactive, rapid UBT based on the LARA system and suggests the need for its more detailed evaluation.