Bleeding diathesis purely from vitamin K deficiency is rarely seen in adults. However mild vitamin K deficiency in the form of a slightly prolonged prothrombin time (PT) is commonly seen in hospitalized patients due to the poor oral intake, fat malabsorptive disorders, malignancy, broad spectrum antibiotic use especially cephalosporins and liver or renal disease.
Vitamin K is necessary for synthesis of coagulation factors II (prothrombin), VII, IX and X in the liver. In the absence of vitamin K, the liver will synthesize inactive precursor proteins known as proteins induced by the absence of vitamin K (PIVKA's). Because vitamin K is fat-soluble, it can only be absorbed from the intestine in the presence of bile salts. The body's capacity to store vitamin K is very low and the half-life of the vitamin K- dependent coagulation factors is short . Because of this, deficiency can occur quickly if the intake is not sufficient. read more