A 48-year-old man presents with deepening jaundice and ascites. Prothrombin time is markedly prolonged. Intravenous vitamin K is administered for three days, and the repeat prothrombin time shows no correction. This result indicates that the prolonged prothrombin time is due to:

• A Vitamin K deficiency from fat malabsorption
• B Warfarin effect from inadvertent drug ingestion
• C Consumption coagulopathy with disseminated intravascular coagulation
• D Impaired hepatic synthesis of coagulation factors ✓

Explanation

Vitamin K acts as a cofactor for gamma-carboxylation of factors II, VII, IX, and X in the liver, and its deficiency states respond to parenteral vitamin K within 24 to 48 hours. Failure of correction after adequate replacement demonstrates that the synthetic capacity of the liver itself has failed, which is one of the most ominous prognostic markers in acute and chronic liver disease. Warfarin effect and malabsorptive vitamin K deficiency would both correct, and DIC requires additional evidence such as falling platelets and fibrinogen.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.