Which clotting factors are deficient in vitamin K deficiency?

Vitamin K plays a crucial role in the synthesis of certain clotting factors in the liver. Specifically, it is essential for the post-translational modification of coagulation factors, allowing them to bind calcium ions and function properly within the coagulation cascade.

In cases of vitamin K deficiency, the factors that become deficient or dysfunctional are those that are synthesized in a vitamin K-dependent manner. These factors are specifically prothrombin (factor II), and factors VII, IX, and X. These factors are critical in both the intrinsic and extrinsic pathways of coagulation, and their deficiency can lead to increased bleeding and coagulopathy.

The other choices include factors that are not dependent on vitamin K for their synthesis. For example, factor I (fibrinogen), factor III (tissue factor), and factor IV (calcium) do not require vitamin K. Factors V, VII, and VIII also do not all relate to vitamin K status, with factor V being independent of vitamin K and factor VIII being involved in different pathways of coagulation.

Therefore, the deficiency of factors II, VII, IX, and X directly correlates with vitamin K deficiency, making this the correct answer. Understanding the role of vitamin K in coagulation is essential