Building and Clinical Use of Activated Plasma Clotting Time Test and the Value of APCT on Predicting the Bleeding Due to Leukemia Chemotherapy-Induced Thrombocytopenia.

Objective This study was aimed to determine the optimal concertration of C-PG in activated plasma clotting time (APCT) test and build the APCT test.To investigate the value of activated plasma clotting time test (APCT) on predicting the bleeding due to Leukemia chemotherapy-induced thrombocytopenia.

Method We collected healthy blood donors’venous blood, prepared watched platelet suspension and platelet rich plasma in a normal way to which we add different concertrations of C-PG, then test expression of AnnexinV in the surface of activated platelet by FCM. Prepared platelet rich plasma and platelet poor plasma in a normal way to which we add different concertrations of C-PG, then count the plasma clotting time.Forty-one patients with leukemia chemotherapy, twenty-one patients with petechiae or epistaxis or gum bleeding and twenty patients without bleeding symptoms, were involved in the test. Drawed their venous blood and collected in 3.2% buffered sodium citrate(9:1), the platelet counts and APCT, PT, APTT, TT, Fig were assesed.

Result Bleeding group’s APCT was obviously prolonged contrast to the non-bleeding group’s. Platelet counts and APCT of the bleeding group and the non-bleeding group were (7.2±2.9) ×10⁹/L, (105.9±8.1)s and (23.0±12.2) ×10⁹/L,(71.4±9.0)s respectively. There was significant difference between the two groups (P<0.01). Using APCT≥90s as the cut-off point to predict the bleeding caused by chemotherapy-induced thrombocytopenia, the sensibility was 100%, and the specificity was 95.7%. Using platelet counts ≤15*10⁹/L, the sensibility and the specificity was 95.2% and 69.0%. PT, APTT, TT, Fig of the bleeding group and the non-bleeding group were 11.7±1.1)S,(31.5±1.3)S,(11.1±1.2)S,(2.37±0.41)g/L and (12.1±0.8)S,(30.8±2.1)S,(10.7±0.9)S,(2.64±0.27)g/L respectively. The results of the two groups were all not significantly different (P>0.05).

Conclusion APCT is a good indication of predicting the bleeding due to leukemia chemotherapy -induced thrombocytopenia.