Which statement is most appropriate for DIC:
Ans: B (Increased D dimer) Ref: Harrison's Principles of Internal Medicine, 18th ed Explanation: Disseminated Intravascular Coagulation DIC is a clinicopathologic syndrome characterized by widespread intravascular fibrin formation in response to excessive blood protease activity that overcomes the natural anticoagulant mechanisms. The most common findings are bleeding ranging from oozing from venipuncture sites, petechiae, and ecchymoses to severe hemorrhage from the gastrointestinal tract, lung, or into the CNS. In chronic DIC. the bleeding symptoms are discrete and restricted to the skin or mucosal surfaces. The hypercoagulability of DIC manifests as the occlusion of vessels in the microcirculation and resulting organ failure. Thrombosis of large vessels and cerebral embolism can also occur. Hemodynamic complications and shock are common among patients with acute DIC. The mortality ranges from 30 to >80% depending on the underlying disease, the severity of the DIC. and the age of the patient. Lab Findings Prolongation of PT and/or aPTT. Platelet counts 1,00,000/L3 or a rapid decline in platelet numbers. Presence of schistocytes (fragmented red cells) in the blood smear: and Elevated levels of FDP. The most sensitive test for DIC is the FDP level. DIC is an unlikely diagnosis in the presence of normal levels of FDP. The D-dimer test is more specific for detection of fibrin--but not fibrinogen--degradation products and indicates that the crosslinked fibrin has been digested by plasmin. Because fibrinogen has a prolonged half-life, plasma levels diminish acutely only in severe cases of DIC. High-grade DIC is also associated with levels of antithrombin III or plasminogen activity <60% of normal. Common Clinical Causes of Disseminated Intravascular Coagulation Sepsis Immunologic disorders * Bacterial Staphylococci, streptococci, pneumococci, meningococci, gram-negative bacilli * Viral * Mycotic * Parasitic * Rickettsial * Acute hemolytic transfusion reaction * Organ or tissue transplant rejection * Graft-versus-host disease Trauma and tissue injury Drugs * Brain injury (gunshot) * Extensive burns * Fat embolism * Rhabdomyolysis * Fi&rinolyftc agents * Aprctimn * Warfarin (especially in neonates with protein C deficiency) * Prothrombin complex concentrates * Recreational drugs (amphetamines) Vascular disorders Envenomation * Giant hemangiomas (Kasabach- Merritt syndrome) * Large vessel aneurysms (e.a., aorta} * Snafee * Insects Obstetrical complications Liver disease * Abruptio placentae * Amnio tic-flu id embolism * Dead fetus syndrome * Septic abortion * Fulminant hepatic failure * Cirrhosis * Fatty liver of pregnancy Cancer Miscellaneous * Adenocarcinoma (prostate, pancreas, etc.} * Hematologic malignancies (acute promyelocytic leukemia) * Shock * Respiratory distress syndrome * Massive transfusion
Increased fibrinogen
Increased D dimer
Resolves if causative factor removed
Absence of bleeding abnormalities rules out DIC
Blood