Influence of proton pump inhibitor treatment on Helicobacter pylori stool antigen test

AIM： To investigate the effects of proton pump inhibitor （PPI） treatment on stool antigen test using the TestMate pylori enzyme immunoassay. METHODS： This study assessed 28 patients [16 men and 12 women; mean age （63.1 ± 5.9） years; range, 25-84 years] who underwent stool antigen test and urea breath test （UBT） before and after PPI administration. RESULTS： Using the UBT as the standard, the sensitivity, specif icity and agreement of the stool antigen test in all 28 patients were 95.2%, 71.4%, and 89.3%, respectively, before PPI administration, and 88.9%, 90.9%, and 89.3%, respectively, after PPI treatment. Mean UBT values were 23.98% ± 5.33% before and 16.19% ± 4.75% after PPI treatment and, in 15 patients treated for ≥ 4 wk, were signif icantly lower after than before 4 wk of PPI treatment （12.58% ± 4.49% vs 24.53% ± 8.53%, P = 0.048）. The mean optical density （A450/630） ratios on the stool antigen test were 1.16 ± 0.20 before and 1.17 ± 0.24 after PPI treatment （P = 0.989）, and were 1.02 ± 0.26 and 0.69 ± 0.28, respectively, in the group treated for 〉 4 wk （P = 0.099）.