Clot waveform of APTT has abnormal patterns in subjects with COVID-19

Abstract In Coronavirus disease 2019 (COVID-19) subjects, recent evidence suggests the presence of unique coagulation abnormalities. this study, we performed clot waveform analyses to investigate whether specific modulations are observed in COVID-19 subjects. We analyzed second derivative absorbance routine APTT tests using an ACL-TOP system. high frequencies abnormal patterns second-derivative curves that could be classified into early shoulder type, a late or biphasic maximum first-derivative and peak levels, low minimum level These were not subjects with disseminated intravascular coagulation. also patients lupus anticoagulant, hemophilia, factor IX deficiency. The plasma fibrinogen levels might involved waveforms, especially levels. appear highest frequency at around 2 weeks after onset associated severity COVID-19. results suggest possible coagulopathy