Increased plasma level of interleukin-6 in disseminated intravascular coagulation.

Plasma interleukin-6 (IL-6) was higher in patients with disseminated intravascular coagulation (DIC) than in those without DIC. Levels of IL-1 beta and TNF alpha were also significantly higher in patients with DIC. Plasma IL-6 was highest in patients with underlying sepsis and was also high in those with advanced solid cancer. Levels were high in some patients with acute promyelocytic leukaemia and were significantly higher in patients with organ failure than in those without this complication. Plasma IL-6 was higher in DIC patients showing a poor response to therapy than in those with a good response. Incubation with IL-6 caused significant increases in tissue factor activity in mononuclear cells and release of plasminogen activator-1 antigen from human umbilical vein endothelial cells. As increases in IL-6 might give rise to hypercoagulable and hypofibrinolytic states, this may be a cause of DIC and be related to prognosis and organ failure.