A study of beta-thromboglobulin and platelet factor-4 plasma levels in steady state sickle cell patients

To evaluate the platelet function in sickle cell syndromes we measured the beta-thromboglobulin (beta-TG) and platelet factor 4 (PF-4) plasma values of 45 patients suffering from homozygous sickle cell anaemia (10) and sickle cell beta-thalassaemia (35) in steady state. The results were compared to those of 32 normal controls. Both the beta-TG and PF-4 levels were found to be significantly higher in patients than in controls but the beta-TG:PF-4 ratio was significantly lower in the patients group. This finding and the absence of any statistical correlation between platelet number and beta-TG or PF-4 indicate that platelets seem to be somehow activated in sickle cell syndromes, both in homozygotes and sickle cell/beta-thalassaemia heterozygotes. This platelet activation seems to exist even in steady state sickle cell disease patients, regardless of the functional status of the spleen.