[Clinical significance of the radioimmunological determination of beta-thromboglobulin and platelet factor 4].

Recently new radioimmunoassay methods have been established to measure plasma concentrations of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4), platelet release products which are set free when platelets aggregate. Plasma concentrations of beta-TG and PF4 were investigated in disorders with increased thromboembolic risk. Extremely high concentrations of these platelet proteins were found in patients with venous thrombosis, pulmonary embolism, polycythemia vera, and chronic renal failure. Moderately increased beta-TG and PF4 levels were observed in patients with peripheral vascular disease, coronary artery disease, chronic rheumatoid arthritis, multiple myeloma, and diabetes mellitus. These data indicate, that plasma concentrations of beta-TG and PF4 are useful parameters for the evaluation of the "in vivo" platelet activity. By using these new methods for clinical applications special blood sampling conditions have been taken into account; moreover one has to consider that the plasma levels of the platelet "release products" are dependent from renal function.