Disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) is a pathologicalprocess in the body where the bloodstarts to coagulatethroughout the whole body. This depletes the body of its plateletsand coagulation factors, and there is a paradoxically increased risk of haemorrhage. It occurs in critically ill patients, especially those with Gram-negativesepsis(particularly meningococcalsepsis) and acute promyelocytic leukemia.

Causes

There are a variety of causes of DIC, all usually causing the release of chemicals into the blood that instigates the coagulation.

• Sepsis, particularly with gram-negative bacteria.
• Obstetric complications, with chemicals from the uterusbeing released into the blood, or from amniotic fluidembolisms, and eclampsiacan be causes.
• Malignant cancers, or widespread tissue damage (e.g. burns), or hypersensitivityreactions all can produce the chemicals leading to a DIC.
• Envenomation by some venomous snakes such as the Stephens Banded Snake, Hoplocephalus stephensi (from the family of Elapidae).

Diagnosis

Although numerous blood testsare often performed on patients prone to DIC, the important measures are: full blood count(especially the plateletcount), fibrin degradation productsor D-dimertests (markers of fibrinolysis), prothrombin timeor INRand fibrinogenlevels. Decreased platelets, elevated FDPs or D-dimers, high PT/INR and decreased fibrinogen are markers of DIC.

Pathophysiology

Various factors can activate the system of coagulation, but the end result is formation of fibrin, a mesh-like protein. The fibrin deposition can block blood vessels, leading to ischemicdamage to some tissues. As well as this, red blood cellsare damaged as they get shredded by the fibrin, leading to microangiopathic hemolytic anemia(MAHA).

Treatment

The underlying cause must be treated initially. Anticoagulants are not given, as by now all the coagulation factors and platelets have been used up. These must be replaced, by platelet transfusionand fresh frozen plasma, to restore normal levels.

DIC results in lower fibrinogen(as it has all been converted to fibrin), and this can be tested for in the hospital lab. A more specific test is for "fibrin split products" (FSPs) or "fibrin degradation products" (FDPs) which are produced when fibrin undergoes degradation when blood clots are dissolved by fibrinolysis.

In some situations, infusion with antithrombinmay be necessary. A new development is drotrecogin alpha(Xigris®), a recombinantactivated protein Cproduct. Activated Protein C (APC) deactivates clotting factors Vand VIII, and the presumed mechanism of action of drotrecogin is the cessation of the intravascular coagulation. Due to its high cost, it is only used strictly on indication in intensive carepatients.

The prognosis for those with DIC, depending on its cause, is often grim, leading the acronym to be known colloquially as "death is coming" [1].ja:播種性血管内凝固症候群 no:Disseminert intravaskulær koagulasjon

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It uses material from the http://en.wikipedia.org/wiki/Disseminated+intravascular+coagulation Wikipedia article Disseminated intravascular coagulation.