Protein C deficiency
Two subtypes are described. Type 1 deficiency refers to reduced protein C antigen and activity levels due to mutation in the PROC gene. Type 2 deficiency refers to a qualitative defect (reduced protein C function with normal antigen levels) also caused by mutation in the PROC gene.
Most cases are heterozygous, although rare cases of homozygous or compound heterozygous mutation have been described. If a mutant allele is inherited from both parents, the results can be severe deficiency of protein C, causing neonatal purpura fulminans at birth.
Acquired cases of protein C deficiency can develop in a variety of scenarios, including hepatic congestion in the setting of right heart failure, severe liver disease, vitamin K deficiency, sepsis, bacterial infection, uremia, acute thrombosis, warfarin or vitamin K antagonist use, certain chemotherapy agents, and disseminated intravascular coagulation.
Patients with protein C deficiency are at an increased risk of developing VTE due to immobility, surgery, trauma, pregnancy, oral contraceptive use, or cancer.
D68.59 – Other primary thrombophilia
76407009 – Protein C deficiency disease
Differential Diagnosis & Pitfalls
Drug Reaction Data