This study was undertaken to determine the levels of protein C antigen and activity and protein C inhibitor in sequential plasma samples of disseminated intravascular coagulation (DIC) patients. Our normal range for both protein C antigen and activity is 70 to 130 U/dL, and protein C inhibitor is 65 to 135 U/dL. A decreased level of protein C activity was found in 96% of the plasma samples from individuals with DIC; the protein C antigen was decreased in 73%. The inhibitor of protein C was decreased in all samples. Analysis of serial samples from patients with DIC reveals that protein C activity and antigen and protein C inhibitor decrease progressively during the initial stages of DIC and remain at a low level for 24 to 48 hours before gradually returning toward normal in nonfatal cases. The protein C activity decreases in parallel with protein C inhibitor and is lower than protein C antigen. In a fatal case of DIC, protein C activity and protein C inhibitor rapidly decreased to undetectable levels; however, protein C antigen was gradually decreasing but still detectable at time of death. In DIC, a discrepancy initially occurs between the activity and antigen of protein C, suggesting a complex with the inhibitor or other inactive forms of protein C. Protein C appears to play a major role in the control of DIC.
Serial studies of protein C and its plasma inhibitor in patients with disseminated intravascular coagulation
- Share Icon Share
- Tools Icon Tools
- Search Site
- PDF LinkPDF
RA Marlar, J Endres-Brooks, C Miller; Serial studies of protein C and its plasma inhibitor in patients with disseminated intravascular coagulation. Blood 1985; 66 (1): 59–63. doi: https://doi.org/10.1182/blood.V66.1.59.bloodjournal66159
Download citation file: