Vitamin K is used in both nutritional deficiency and warfarin overdose (discussed previously). Vitamin K is involved in the production of factors II, VII, IX, and X. If vitamin K is not in the diet, if there is an issue with the absorption of vitamin K, or if excessive antibiotic use has destroyed the vitamin K-producing gut flora, vitamin K deficiency can result. The bleeding seen in vitamin K deficiency is like that seen with other coagulation factor deficiencies- deep bleeding.
Laboratory diagnosis of vitamin K deficiency:
- PT and aPTT will both be prolonged since the vitamin K-dependent factors are found in the intrinsic, extrinsic, and common coagulation pathways.
- Correction of the PT and aPTT if the patient receives vitamin K.
