INCREASED VASOOCCLUSIVE CRISIS IN “O” BLOOD GROUP SICKLE CELL DISEASE PATIENTS: ASSOCIATION WITH UNDERLYING THROMBOSPONDIN LEVELS.

Abstract

Abstract:Objectives: To explore the incidence of vaso-occlusive crisis (VOC) in Blood Group “O” sickle cell disease (SCD) patients, and correlate it with the blood group and thrombospondin (TSP) levels.Methods: In 89 consecutive SCD patients, blood samples were obtained for vWF antigen, collagen binding activity, blood group typing, C-reactive protein, variant hemoglobin analysis (HPLC), Serum TSP 1 and TSP 2 levels, complete blood counts, liver function tests, LDH and renal function tests during VOC episodes and in steady state conditions.Results: In the steady state SCD patients (n=72), “O” blood group patients (n=37) showed significantly higher median serum TSP 1 and TSP 2 levels than the non “O” blood group patients [n=35] [p <0.05, Mann-Whitney test], with an inverse relation between VWF:Ag, Factor VIII:C and TSP levels. Furthermore, the serum TSP 1 and TSP 2 levels were significantly higher in patients presenting with acute VOC [n=17], and in those with repeated VOC’s (group 1, n=16) especially amongst those patients with blood group “O” [p, <0.05, Mann-Whitney test].Conclusions: The study shows that there was an inverse relation between TSP and vWF levels, in blood group “O” SCD patients with an upregulation of the TSP levels. Expectedly, during active VOC crisis, the TSP 1 and TSP 2 levels were significantly elevated.  Key Words: VOC; SCD; TSP; vWD; Blood groups