The role of platelet reactivity in the pathogenesis of pulmonary artery hypertension in thalassemic patients: a case–control study

Background: The incidence of thromboembolic events is higher than normal in the majority of thalassemic patients, even from a very young age, particularly in patients who have undergone splenectomy and/or who have undergone transfusion infrequently. Objective: The objective of the study was to detect whether changes in mean platelet component (MPC) might reflect changes in platelet activation status in thalassemic patients (thalassemia major, nonsplenectomized, and splenectomized). The study also aimed to correlate the effect of platelet activation status and splenectomy on the development of pulmonary hypertension (PH). Patients and methods: A case–control study carried out on 50 pediatric patients diagnosed as thalassemia major at the Children Hospital of Assiut University. They were classified into 21 splenectomized and 29 nonsplenectomized patients. Results: MPC and platelet aggregation % was significantly lower in thalassemic patients compared with the control group, 0.029) and 0.000, respectively ( P =0.000). PH was significantly present in splenectomized as compared with nonsplenectomized thalassemic patients, 81 and 24.1%, respectively ( P =0.000). Platelet count was significantly higher in splenectomized as compared with nonsplenectomized thalassemic patients ( P =0.000), as well as in PH thalassemic as compared with normotensive thalassemic patients ( P =0.001). There was no significant difference in MPC and platelet aggregation % between splenectomized and nonsplenectomized thalassemic patients as well as between PH thalassemic and normotensive thalassemic patients. Conclusion: We concluded that splenectomy and consequently thrombocytosis play an important role for the development of PH in thalassemic patients.