Helicobacter pylori Upregulates Peripheral Platelet Counts Mainly in Female Patients

To evaluate the influence of Helicobacter pylori and sex difference on peripheral platelet counts, dyspeptic patients without immunohaematologic disorders were evaluated. H. pylori infection was verified with the rapid urease test and serum anti-H. pylori IgG antibody. Platelet counts were analysed with a reference to H. pylori infection and sex difference. Among H. pylori-eradicated patients, changes in platelet counts were separately evaluated. Totally, 655 patients were enrolled: 340 patients were infected with H. pylori and 178 patients received eradication therapy, with a success rate of 88.2% (157/178). Females with H. pylori infection definitely manifested elevated platelet counts (infected vs. uninfected 244 ± 57 vs. 219 ± 54 × 109/l; p < 0.0001). H. pylori eradication reduced peripheral platelets by 8 weeks, 5–6 months, 1, 2 and ≧3 years after eradication in females from 248 ± 54 to 237 ± 49, 237 ± 54, 229 ± 48, 238 ± 61 and 232 ± 50 × 109/l (p = 0.0003, 0.0182, 0.0041, 0.0398 and 0.0289), respectively. In males, the reduction was verified by 8 weeks, 1 year and ≧3 years from 226 ± 52 to 217 ± 47, 214 ± 44 and 200 ± 49 × 109/l (p = 0.0464, 0.0164 and 0.0016), respectively. In conclusion, H. pylori infection upregulates platelet counts mainly in females, and eradication reduced peripheral platelets in both sexes. Females appeared more susceptible to H. pylori infection than males with regard to upregulation of platelet counts.