Neuroradiology

Disseminated intravascular coagulation

(DIC), an acquired disorder of coagulation that follows many systemic diseases, most frequently obstetrical catastrophes, metastatic malignancies, massive trauma and bacterial sepsis. In such conditions a potent thrombogenic stimulus, e.g. tissue factors released from necrotic tissue in traumatized patients or endotoxins released by bacteria in septic patients, causes the deposition of small thrombi and emboli throughout the microvasculature. An early thrombotic phase is then followed by a phase of procoagulant consumption and secondary fibrinolysis. Continued fibrin formation and fibrinolysis lead to haemorrhage from the depletion of coagulation proteins and platelets, and the antihaemostatic effects of fibrin degradation products. DIC may manifest itself in an acute life-threatening form with patients bleeding profusely after venepuncture and presenting with intracranial haemorrhage. A more indolent form of DIC may also cause neurological manifestations. Autopsy examinations reveal evidence of intravascular thrombosis in situ. The main neurological manifestation of DIC in this case is diffuse encephalopathy. The diagnosis of chronic DIC should be considered if blood levels of fibrin-split products are elevated.

GS