Tests for vitamin K levels are not widely available and are rarely ordered. They are not typically used to screen for or help diagnose vitamin K deficiencies because a lack of vitamin K is usually discovered when unexpected or excessive bleeding or easy bruising occurs. The primary test used to investigate the bleeding is a prothrombin time (PT) ....
Any of a group of substances that, in very small amounts, are essential for normal growth, development, and metabolism. They cannot be synthesized in the body (with a few exceptions) and must be supplied by the diet.