[13C-urea breath test for the diagnosis of Helicobacter pylori infection. Comparison with histology]

Abstract

Objective: This study was to evaluate the 13C-urea breath test for the diagnosis of Helicobacter pylori infection compared with pathological data of gastric antrum and fundus endoscopic biopsies.

Methods: In 95 patients, the results of the 13C-urea breath test were retrospectivally compared with histology (standard and Giemsa staining).

Results: Using a ROC curve, the best cut-off value for the 13C-urea breath test was determined at + 3 delta 0/00 of breath isotopic enrichment. Compared with histology, the diagnostic values of the 13C-urea breath test were: sensibility 90.3%, specificity 97%, positive predictive value 98.2%, negative predictive value 84%. The false negative results of the breath test (6 out of 95) were obtained in patients with few H. pylori present in antral biopsies, or in patients under omeprazole therapy. The urea breath test was well correlated with the inflammation of the gastric mucosa (P < 0.0001). The isotopic enrichment in breath was well correlated to the number of H. pylori estimated by histological analysis (P < 0.05).

Conclusions: The 13C-urea breath test is a non invasive and non radioactive diagnostic tool for H. pylori infection. Its excellent positive predictive value and its good negative predictive value guarantee its usefulness in clinical practice, especially for the control of eradication after anti-H. pylori therapy.