Disseminated intravascular coagulopathy

Disseminated intravascular coagulation (DIC) is not a disease but a pathological process with widespread thrombus formation in small vessels; it occurs in many systemic conditions that stimulate the intravascular clotting mechanism. There may be widespread tissue involvement, and any tissue in the body may be affected, especially in the kidney, brain, liver, heart, and lungs. This abnormal coagulation is now commonly referred to as disseminated intravascular coagulopathy. It is prone to occur in obstetrical complications, in cancer, after transplantations, and where there has been tissue damage, such as burning, crushing, and surgery, all of which release thromboplastin into the circulation. It may also occur in Gram negative bacterial systemic infections, in antigen-antibody reactions, and in thrombotic thrombocytopenic purpura. When the eye is involved, the thrombi occur in the choriocapillaris, and are usually limited to the submacular and peripapillary choroid. The anterior parts of the eye generally escape involvement. Visual symptoms may be early, and may be due to central choroidopathy or to secondary retinal detachment.