Vitamin K's primary purpose is to clot blood, so when you don't have enough Vitamin K, your blood does not clot as well as it should. This is called a Hemorrhage, or when you cannot stop bleeding. Syptoms include easy brusing, nose bleeds, blood in urine, blood in stool, and excessive menstral bleeding. Anybody from Adults to Infants can get this disorder. In fact, vitamin K deficiencies are common in young children because human female's milk is low in vitamin K, and the bacteria that naturally produce K-2 in your intestine are not yet developed. In most cases, this would lead to intracranial hemorage, or internal bleeding within the brain. Other than that, to be diagnosed with a Vitamin K deficiency is uncommon, because it is very common in foods and nature.
    Also, because Vitamin K is required in the binding of bone minerals, a deficiency could cause ostheoperosis.