A patient with severe chronic liver dysfunction presents with gingival bleeding and blood in the stool. Which vitamin deficiency is most likely?

• A. Vitamin A deficiency
• B. Vitamin K deficiency
• C. Riboflavin deficiency
• D. Folic acid deficiency

Answer: (B)

The key idea is that liver disease can cause a bleeding tendency by impairing the body’s ability to clot and by reducing the absorption of fat-soluble vitamins, especially vitamin K. Vitamin K is essential for activating the clotting factors II, VII, IX, and X through gamma-carboxylation. In severe liver dysfunction, production of these clotting factors is already compromised, and if vitamin K is deficient (often due to malabsorption of fats because bile flow is impaired in liver disease), the activation of these factors is further reduced. The result is an increased tendency to bleed, which fits with gingival bleeding and blood in the stool.

Other deficiencies listed do not typically present with mucosal bleeding or GI bleeding in this context: vitamin A deficiency causes vision and skin issues; riboflavin deficiency causes mouth and skin problems but not a bleeding tendency; folic acid deficiency causes megaloblastic anemia.