Vitamin K deficiency leads to what symptom?

• A. Hypertension
• B. Bleeding
• C. Anemia
• D. Weight gain

Answer: (B)

Vitamin K is required for gamma-carboxylation of several clotting factors (II, VII, IX, X) and the proteins C and S. This modification enables these proteins to bind calcium and assemble on phospholipid surfaces, which is essential for proper coagulation. When vitamin K is deficient, these factors are undercarboxylated and inactive, leading to impaired clotting and a tendency to bleed. Clinically, this presents as easy bruising, mucosal or GI bleeding, and a prolonged prothrombin time. Hypertension, anemia, or weight gain are not direct manifestations of vitamin K deficiency. Anemia could occur secondary to significant bleeding, but the primary issue is impaired coagulation causing bleeding.