INTRODUCTION
Immune (idiopathic) thrombocytopenic purpura (ITP) is an acquired disease characterized by a temporary or permanent decrease in the platelet count that results from the effects of immune–mediated anti–platelet antibodies (1). Its prevalence in adults is approximately 5–10/100.000 and it is more common among females in the adult age group. It is usually associated with a chronic progression and an elevated risk of bleeding due to the severity of thrombocytopenia (2,3).
Thrombocytopenia may be induced by antibodies that are produced in response to pathogen antigens and cross–react with platelets in certain infections, which mainly include viral infections but also consist of bacterial infections. Particularly, lipopolysaccharides in bacteria are reported to bind to the platelet membrane and trigger platelet phagocytosis (4). Similarly, although no mechanism has been proposed to explain how Helicobacter pylori (H. pylori) could be involved in the pathogenesis of immune–mediated platelet destruction, the role of bacterial factors such as the cytotoxin–associated gene A (CagA) protein are currently being investigated (5).
The relationship between H. pylori infection and ITP was first defined in 1998 by Gasbarrini et al. in a study where they reported a high platelet count in 8 of their 11 ITP patients (6). Since then, numerous studies on H. pylori eradication in ITP have been published. However, it is still controversial whether or not H. pylori eradication always increases the platelet count in patients diagnosed with ITP. Comprehensive reviews suggest that eradication therapy would need to be considered if a H. ​​pylori infection is detected in patients with typical ITP (7). Studies in the literature have generally focused on the effects of the eradication of H. ​​pylori infection on increasing the platelet count in ITP patients and the effects of H. ​​pylori positivity on the response to the standard first–line ITP treatment are not clear. The present study aims to determine whether or not the response to the first–line treatment is affected by H. pylori –positive and –negative states in patients diagnosed with ITP.