Protein C deficiency
ICD-10 D68.5 · ICD-11 3B61.0Y.1

Treatment of Protein C Deficiency with Severely Reduced Protein C Activity (<1 IU/dL), Outside Acute Events

This protocol covers patients with severe protein C deficiency — defined by a protein C activity below 1 IU/dL — who are not currently experiencing acute disseminated intravascular coagulation, purpura fulminans, or an active venous thromboembolism event.

Clinical Scenario

Protein C activity <1 IU/dL

Severely reduced protein C activity places patients at high risk for recurrent thrombotic complications including purpura fulminans, DIC, and venous thromboembolism. The absence of an acute event creates the clinical window in which long-term secondary prophylaxis is the primary management goal.

Management Approach

Long-term secondary prophylaxis is the cornerstone of management in this setting. The approach involves protein C concentrate and/or anticoagulation — the specific strategy, combination, and sequencing are set out in the full structured protocol.

Treatment Goals

D-dimer monitoring is used to confirm adequacy of replacement or anticoagulation. A rising or markedly elevated D-dimer may signal recurrent thrombotic risk in this population.

Instant Access to Structured Evidence-Based Regimens

References

DOI: 10.1111/j.1365-2516.2008.01838.x

Outside of DIC, PF, or an acute VTE event, most affected infants have been managed for long-term secondary prophylaxis with protein C concentrate or therapeutic anticoagulation using either low-molecular-weight heparin or high-intensity warfarin.

Monitoring for evidence of coagulation activation with D-dimer is useful to confirm adequate replacement or anticoagulation therapy; in the authors' experience, and as previously published in the neonate, a markedly elevated or rapidly rising D-dimer has often heralded the onset of recurrent VTE, PF, or DIC in young patients with severe protein C deficiency.

View source ↗