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Chronic idiopathic thrombocytopenic purpura (ITP) is an acquired disease characterized by a low platelet count caused by an immunological peripheral platelet destruction or a decreased platelet production. Several studies have shown increased reactive oxygen species (ROS) levels in chronic ITP and also a possible association between Helicobacter pylori (H. pylori) infection and immunological peripheral platelet destruction.

To evaluate whether patients with chronic ITP and H. pylori infection exhibit higher ROS levels compared to patients with chronic ITP and no H. pylori infection and whether there are statiscally significant differences between the two groups.

We studied 29 patients with chronic ITP (median age 39 years) hospitalized in the Clinic of Hematology, Filantropia City Hospital, Craiova, Romania, between 2014 and 2016 (informed consent obtained). All patients were diagnosed with ITP, other causes of thrombocytopenia having been ruled out by bone marrow aspiration. The patients were divided in two groups: patients with ITP and H. pylori infection (group A) and patients with chronic ITP without H. pylori infection (group B). Serological tests (ELISA) were used to indicate the presence of a H. pylori infection and reactive oxygen species were evaluated by FORT (Free Oxygen Radicals testing) test from a single drop of capillary blood, at the time of diagnosis, before the administration of any drug (the normal value of FORT is considered less than 2.3 mmol/L H₂O₂), using a CR3000 analyzer (Callegari SpA, Parma, Italy). The differences between the two groups were assessed using the Student T-test and a p-value of less than 0.05 was considered statistically significant.

Group A consisted of 11 patients positive for H. pylori, whereas group B included 18 patients with no H. pylori infection. ROS levels, measured by the FORT test, were elevated in both groups (between 2,8 – 3.6 mmol/L H₂O₂). However, statistically significant differences were found in favour of group A, with higher ROS values than group B. The A group also associated lower platelet counts and more patients pertaining to this group relapsed in comparison to group B.

In chronic ITP, increased levels of ROS are associated with elevated autoantibody production. Autoantibodies are involved in platelet destruction via highly a immunogenic activity. On the other hand, association of H. pylori infection, via chronic inflammation, led to a supplementary increase in ROS levels and increased platelet destruction.