Platelet Aggregation Study in Patients With Hemoglobin Eβ Thalassemia in India

Abstract

Hemoglobin Eβ thalassemia is a major public health problem in India, especially in the state of West Bengal. Various thromboembolic events are common, especially in splenectomized patients. Platelet hyperactivity most likely plays a pathogenetic role. To investigate the role of platelets in hypercoagulability, platelet aggregation tests were undertaken in the present study. Platelet-rich plasma from 30 patients with Eβ thalassemia (15 splenectomized and 15 nonsplenectomized) were studied and compared with 15 healthy participants. The 4 agonists used were adenosine 5-diphosphate, adrenaline (epinephrine), collagen, and ristocetin. The current study shows both splenectomized and nonsplenectomized patients had abnormal aggregation compared to normal healthy controls. Splenectomized patients had higher platelet aggregation than nonsplenectomized patients for all 4 agonists; but statistically significant difference among 2 groups was found only for collagen. The present study confirms a role of splenic absence in platelet hyperaggregation.

Deferiprone, an iron chelator, alleviates platelet hyperactivity in patients with β-thalassaemia/HbE

“…There are several factors that contribute to platelet hyperactivity, including increased platelet counts, 22 , 23 the release of hemin from haemolyzed red blood cells, 24 and oxidative stress inducing the generation of microparticles from red blood cells and platelets. 25 , 26 Microparticles promote platelet–platelet and platelet–leukocyte aggregation.…”

“…19,20 In addition, pulmonary hypertension caused by chronic microembolization in the lung has been found with high incidence in patients who have undergone splenectomy. 21 There are several factors that contribute to platelet hyperactivity, including increased platelet counts, 22,23 the release of hemin from haemolyzed red blood cells, 24 and oxidative stress inducing the generation of microparticles from red blood cells and platelets. 25,26 Microparticles promote platelet-platelet and platelet-leukocyte aggregation.…”