Platelet density analysis: a tool for the detection of acquired storage pool disease in man

Abstract

The usefulness of platelet density analysis in the detection of acquired storage pool defects was evaluated in human patients. Two groups of patients were investigated: 19 subjects affected with a myeloproliferative disorder (group I) where abnormal platelets are released from the megakaryocytes and 11 patients hospitalized in an intensive care unit (group II) where normal platelets are injured in the circulation. Platelet density distribution after isopycnic centrifugation on a discontinuous stractan density gradient, dense granule markers (serotonin, ATP and ADP) and .alpha. granule markers (intraplatelet .beta.-thromboglobulin and platelet factor 4) were simultaneously determined. An increased proportion of the percentage of light platelets was observed in 16 patients of group I and 9 of group II; an increased ATP/ADP ratio was observed in 12 patients of group I and 10 of group II. Both the tests were abnormal in 11 patients of group I and 9 of group II. In group I, the level of serotonin was low and was related to the percentage of light platelets. The .alpha. granule specific proteins were normal in the 2 groups. Platelet density analysis may serve as a screening test to detect exhausted platelets in human diseases.