A comparative analysis of platelet parameters of sickle cell anemia patients during bone pain crises and in steady states

Abstract

BACKGROUND: Platelet parameters in steady-state sickle cell anemia (SCA) are affected by the red cell sickling, vaso-occlusion, and chronic hemolysis occasioned by the disease; and the occurrence of bone pain crises may further alter these parameters. Knowledge of platelet parameters in SCA augments our understanding of the pathophysiology of the disease and may influence disease management modalities. OBJECTIVES: The objective of the study is to determine and compare platelet parameters of SCA patients during bone pain crises and in steady states. PATIENTS AND METHODS: A longitudinal study involving 50 adult SCA patients who had platelet parameters determined during bone pain crises and later in steady states. Platelet count and platelet indices (mean platelet volume, platelet distribution width, plateletcrit, and platelet-large cell ratio (P-LCR)) were determined through automation. RESULTS: SCA patients during both bone pain crises and steady states had higher mean platelet counts when compared with normal non-SCA reference values. P-LCR was found to be significantly different between the bone pain crises and steady states with mean values of 18.20 ± 5.55 versus 15.96 ± 4.91 respectively; P = 0.034. During the bone pain crises state, platelet parameters did not significantly differ based on the severity of pain. CONCLUSIONS: Platelet count of both steady and bone pain crises states SCA patients were higher than the reference range for the normal non-SCA population. The P-LCR was the only platelet parameter that significantly differed between the two clinical states of SCA as it rose during the bone pain crises state; a finding reflecting increased peripheral platelet activation and the presence of larger circulating platelets during the vaso-occlusive crises.