[Clinical application of laboratory diagnosis: leukemia and DIC]

Plasma levels of molecular markers of hemostatic activation were investigated in 205 samples from patients with haematopoietic malignancies. These markers included thrombin/antithrombin III complex (TAT), D-dimer, plasmin/alpha 2plasmin inhibitor complex (PIC) and thrombomodulin (TM), and were assayed by EIA methods. Samples were divided into 4 groups according to the level of FDP: group A; FDP 10 greater than, group B; 10 less than or equal to less than 20 group C; 20 less than or equal to less than 40, and group D; less than 40. The mean level of each marker except TM increased in the order of group A, B, C and D. However, in many samples belonging to group A the plasma TAT or PIC levels and both were increased in spite of low FDP level. Furthermore, levels of TAT and PIC in several samples belonging to groups C and D were within the normal range. Also, the mean levels of each marker except TM increased in the order of 2, 3, 4, 5 and over 6 points in DIC score according to the criteria of DIC diagnosis by the research committee on DIC of the Ministry of Health and Welfare in Japan. Eight of the 11 samples (72.7%) obtained from cases with a DIC score of 3 points had high plasma levels of TAT, PIC and D-dimer. Plasma levels of these markers were increased after chemotherapy. These findings lead to the following conclusions: 1) FDP reflexed activation of coagulation and fibrinolysis, but 2) FDP was not more sensitive than TAT and PIC, and 3) the increase of FDP rarely resulted from fibrinogenolysis or non-plasmin mediated fibrinolysis. Furthermore, 4) TAT, D-dimer and PIC may serve as sensitive parameters of hemostatic activation in circulating blood and be valuable markers for early diagnosis of DIC.