Screening markers for chronic atrophic gastritis in Chiapas, Mexico

Intestinal-type gastric adenocarcinomas usually are preceded by chronic atr ophic gastritis, Studies of gastric cancer prevention often rely on identif ication of this condition. In a clinical trial, we sought to determine the best serological screening method for chronic atrophic gastritis and compar ed our findings to the published literature. Test characteristics of potent ial screening tests (antibodies to Helicobacter pylori or CagA, elevated ga strin, low pepsinogen, increased age) alone or in combination were examined among consecutive subjects enrolled in a study of H. pylori and preneoplas tic gastric lesions in Chiapas, Mexico; 70% had chronic atrophic gastritis, English-language articles concerning screening for chronic atrophic gastri tis were also reviewed. Sensitivity for chronic atrophic gastritis was high est for antibodies to H. pylori (92%) or CagA, or gastrin levels >25 ng/l ( both 83%), Specificity, however, was low for these tests (18, 41, and 22%, respectively). Pepsinogen levels were highly specific but insensitive marke rs of chronic atrophic gastritis (for pepsinogen I<25 <mu>g/l, sensitivity was 6% and specificity was 100%; for pepsinogen I:pepsinogen II ratio <2.5, sensitivity was 14% and specificity was 96%), Combinations of markers did not improve test characteristics. Screening test characteristics from the l iterature varied widely and did not consistently identify a good screening strategy. In this study, CagA antibodies alone had the best combination of test characteristics for chronic atrophic gastritis screening. However, no screening test was both highly sensitive and highly specific for chronic at rophic gastritis.