Disseminated intravascular coagulation (DIC) is a disorder characterized by massive systemic activation of coagulation with consumption of platelets and coagulation proteins. Normally, when you are injured, certain proteins in the blood become activated and travel to the injury site to help stop bleeding. However, in persons with DIC, these proteins become abnormally active. The disorder presents in a very ill patient as bleeding into the skin (purpura) and other tissues. It arises as a complication of different serious and life-threatening diseases. It covers the continuum of events that occur in the coagulation pathway. Initially there is uncontrolled activation of clotting factors in the blood vessels, causing clotting of blood throughout the whole body. This depletes the body of its platelets and coagulation factors and results in a paradoxical increased risk of bleeding (hemorrhaging). Hence, patients with DIC have a loss of balance between the clot-forming activity of thrombin (enzyme that causes blood to clot) and the clot-lysing activity of plasmin (enzyme that dissolves blood clots). DIC is not a specific diagnosis and its presence always indicates another underlying disease.
The most common causes of DIC are pregnancy (which usually causes DIC when a complication causes material from the inside of the womb to get into the mother’s bloodstream), cancer, serious infections (such as a blood infection known as sepsis), severe head injury, certain poisonous snakebites and surgery. The infections can be from gram-positive and gram-negative septicemia, meningococcemia, typhoid fever, Rocky Mountain spotted fever, viraemia and parasites. The three main symptom groups of DIC are the symptoms of the underlying condition that caused DIC (such as pregnancy, cancer or serious illness), abnormal bleeding and symptoms from abnormal blood clots, such as leg pain from a deep venous thrombosis. Whatever the cause, DIC is a serious condition that can cause permanent organ damage and death. However, if the underlying cause can be corrected, DIC may go away and cause no long-term effects.
Prevention is usually not possible, but is related to the cause. For instance, following sports safety guidelines for children, adolescents and adults could prevent some cases due to head injury. Early treatment of infections with antibiotics may stop them from getting severe enough to cause DIC. Avoidance of snakes can help prevent snakebites. Disseminated intravascular coagulation should be suspected in any individual who has an unexplained tendency toward bleeding and has experienced any clinical condition that introduces coagulation-promoting factors into the circulation. In an acute case of DIC, multiple bleeding sites will be present, bruising of the skin, sudden onset of fever and extensive purpura of the extremities are most likely. Excessive bleeding can appear suddenly and progress rapidly to severe or fatal hemorrhage. Any condition that also causes decreased blood flow can stimulate DIC. Signs and symptoms of a more chronic, or gradual DIC are prolonged bleeding from a venipuncture site, bleeding gums, nosebleeds, bruising easily and the presence of minute, pinpoint red spots caused by bleeding under the layer of the skin.
Diagnosis of DIC begins with the history and physical exam. DIC is usually suspected when a person with a condition known to cause DIC has abnormal bleeding or blood clots. In most cases, the diagnosis is confirmed with blood tests. A series of blood tests, often called a DIC panel, can be ordered when this condition is suspected. The blood tests measure various parts of the clotting mechanism and count the number of cells in the blood. Following diagnosis, the objective of treatment is to determine the under-lying cause of DIC and treat it, because this underlying cause predicts the probable outcome. The presence of inadequate blood components can be overcome with fresh frozen plasma and blood transfusions. Fibrinogen replacement can also occur by transfusion of blood products. When the primary disease cannot be treated, intravenous injections of heparin, a medication used to prevent thrombosis, are sometimes used in combination with replacement therapy. The use of heparin is, however, very controversial because it can cause bleeding itself.