nutritional disorders
Vitamin K Deficiency
Introduction
Vitamin K deficiency results from extremely inadequate intake or fat malabsorption. Risk of bleeding is increased by use of coumarin anticoagulants. Deficiency is particularly common among breastfed infants. It impairs clotting. Diagnosis is suspected based on routine coagulation study findings and confirmed by response to vitamin K. Treatment consists of vitamin K given orally or, when fat malabsorption is the cause or when risk of bleeding is high, parenterally. Vitamin K deficiency decreases levels of prothrombin and other vitamin K–dependent coagulation factors, causing defective coagulation and, potentially, bleeding. Worldwide, vitamin K deficiency causes infant morbidity and mortality. Vitamin K deficiency causes Blood loss , which usually occurs 1 to 7 days postpartum. In affected neonates, birth trauma can cause intracranial hemorrhage. A late form of this disease can occur in infants about 2 to 12 weeks old, typically in infants who are breastfed and are not given vitamin K supplements. If the mother has taken Inhealthy adults,dietary vitamin K deficiency is uncommon because vitamin K is widely distributed in green vegetables and the bacteria of the normal gut synthesize menaquinones. (See also Overview of Vitamins .) 