Usefulness of the APTT waveform for the diagnosis of DIC and prediction of the outcome or bleeding risk

Background: The usefulness of the activated partial thromboplastin time (APTT) waveform has been reported in hemophilia, acquired hemophilia and monitoring for anticoagulants. Material and methods: The APTT waveform was examined in patients suspected of having disseminated intravascular coagulation (DIC) to analyze its usefulness for the diagnosis of DIC or the prediction of the outcome or bleeding risk. Results: DIC with fibrinogen < 2 g/L was frequently associated with infectious diseases (43.3%). The heights of the first derivative peak (1stDP) and second DP (2ndDP) were extremely low in DIC, especially DIC with hypofibrinogenemia, but high in infectious patients without DIC. The peak time and width of the 1stDP and 2ndDP were prolonged in patients with DIC. The heights of the 1(st)DP and 2(nd)DP were markedly low in patients with a poor outcome or those with hemoglobin < 8.0 g/dl. Discussion and conclusion: As bleeding type DIC was observed in infectious DIC, DIC without hypofibrinogenemia might switch to DIC with hypofibrinogenemia by the progression of DIC. The height of the 1(st)DP and 2(nd)DP is useful for the diagnosis of DIC and prediction of the bleeding risk or outcome.