According to the results of H. pylori and CagA antibody tests, the 76 primary ITP patients were then divided into three groups: group A, H. pylori negative (HP-, 30 patients); group B, H. pylori positive but CagA negative (HP+CagA-, 21 patients) and group C, H. pylori positive CagA positive (HP+CagA+, 25 patients). Here, S100A8 is linked to autoimmune thrombocytopenic purpura.