2025 – PAGE 295 – HEMATOLOGY & ONCOLOGY

FACTOR V LEIDEN

Factor V Leiden is an inherited condition in which a mutation of a clotting factor results in thrombophilia (an increased tendency to form clots). Patients can be homozygous or heterozygous for the gene.

• HOMOZYGOUS: These patients may require lifelong anticoagulation if they develop a thrombus (DVT, pulmonary embolism, etc.) and are then found to have the mutation. Women with Factor V Leidenhave a much higher likelihood of having spontaneous abortions and still births.
• HETEROZYGOUS: The majority of these patients go through life without any issues. If discovered, it’s usually an incidental finding and anticoagulation is not needed if there hasn’t been a thrombotic event.

ANTIPHOSPHOLIPID ANTIBODY SYNDROME (APS)

APS is an autoimmune disorder that can cause recurrent thrombosis and pregnancy complications. Symptoms may include DVT, PE, stroke, and recurrent miscarriages. Diagnosis requires at least one clinical manifestation (thrombosis or pregnancy morbidity) plus antiphospholipid antibodies such as lupus anticoagulant (positive), anticardiolipin antibodies (high), and anti-β2-glycoprotein I antibodies (high) on two occasions at least 12 weeks apart. Treat with anticoagulants, including long-term warfarin therapy, along with aspirin in some cases.

PROTEIN C DEFICIENCY

Protein C deficiency is a genetic disorder which increases thrombosis risk. Symptoms may include DVT, PE, and neonatal purpura fulminans. Diagnosis involves measuring protein C activity levels (low) and genetic testing. Treat with anticoagulants, including long-term warfarin therapy. Protein C concentrate is used in severe cases.