Performance of routine Helicobacter pylori tests in patients with atrophic gastritis

Background. Decreased density of H.pylori in atrophic gastritis may lead to low sensitivity of the routine tests. Aims. To evaluate the accuracy of routinely used H.pylori tests in atrophic gastritis. Methods. We compared 5 H.pylori diagnostic tests in 119 dyspeptic patients (28 males/91 females) with a mean age of 67 years (range 55-84). Patients with gastric cancer, peptic ulcer, previous gastric surgery, or those who have received eradication therapy were excluded. The following tests were performed: histology, rapid urease test (RUT), culture, ¹³C- urease breath tests (UBT), and H.pylori IgG/IgA antibody test (serology). Results. Atrophic gastritis was diagnosed in 26.1% of the patients; H.pylori was present in 87.1%. In the group with atrophy, the sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy were as follows: histology (100% for all parameters); UBT (96; 100; 100; 80; 97%); serology (96; 50; 93; 67; 90%); culture (96; 100; 100; 80; 97%); and RUT (78; 100; 100; 40; 81%), respectively. Conclusions. Histology, UBT and culture were the three best tests for diagnosing H.pylori infection. We cannot recommend using serology as a single test in a case of atrophy, but it would be reasonable to combine serology with one of the above tests.