Snapshot A 46-year-old woman presents to the emergency room for a headache that worsens with flexion of the neck. She is started on broad-spectrum antibiotics and prepped for a lumbar puncture. However, laboratory evaluation reveals marked thrombocytopenia and elevated D-dimer. On physical exam, she is noted to have retiform purpura over the toes bilaterally, as well as dusky nasal tip. After platelet transfusion, a lumbar puncture is performed. (Meningitis-induced disseminated intravascular coagulation) Introduction Overview disseminated intravascular coagulation (DIC) is characterized by abnormal widespread activation of clotting Epidemiology Incidence ~1% of all hospitalizations Risk factors trauma sepsis particularly with gram-negative bacteria obstetrical complications acute pancreatitis malignancy nephrotic syndrome transfusions ETIOLOGY Pathogenesis mechanism abnormal activation of coagulation cascade leads to thrombi production, which leads to consumption coagulopathy fibrinolysis occurs at sites of thrombi, and fibrin degeneration products can interfere with coagulation leads to end-organ damage consumption coagulopathy exceeds production of clotting factors in chronic cases, there may be compensation via increased production Presentation Physical exam inspection bleeding and oozing at catheter sites and mucosal surfaces purpura fulminans retiform purpura, particularly at acral sites petechiae and ecchymoses altered mental status vital signs hypotension tachycardia Studies Serum labs coagulation factor consumption elevated PT and aPTT low fibrinogen increased thrombin time decreased factors V and VIII thrombocytopenia fibrinolysis elevated D-dimer Peripheral blood smear with microangiopathic changes schistocytes Differential Heparin-induced thrombocytopenia key distinguishing factor history of recent heparin exposure and positive laboratory testing for heparin-platelet factor 4 antibodies DIAGNOSIS Diagnosis is based on clinical and laboratory findings, including thrombocytopenia, coagulation factor consumption, and fibrinolysis Treatment Medical treat underlying disorder supportive care indication all patients modalities fluids platelet transfusions if < 10,000/μL particularly for those who need urgent procedures fresh frozen plasma consider heparin for any thrombosis Complications Renal failure Liver injury Neurologic symptoms thrombi and hypoperfusion Waterhouse-Friderichsen syndrome adrenal insufficiency secondary to adrenal hemorrhage or infarct commonly caused by Neisseria meningitidis Purpura fulminans characterized by hemorrhagic skin necrosis, often at distal sites, due to thrombi retiform purpura