REVIEW Review: Infectious Diseases and Coagulation Disorders

Infection, both bacterial and nonbacterial, may be associated with coagulation disorders, resulting in disseminated intravascular coagulation and multiorgan failure. In the last few decades a series of in vivo and in vitro studies has provided more insight into the pathogenetic mechanisms and the role of cytokines in these processes. Because of the growing interest in this field, the complexity of the subject, and the fact that many physicians must deal with a variety of infections, current data are reviewed on the association between infectious diseases and the coagulation system. Novel therapeutic intervention strategies that will probably become available in the near future are mentioned, along with those of special interest for infectious disorders for which only supportive care can be given. Systemic infections may be complicated by activation of the coagulation cascade, varying from subclinical activation, which is indicated by a rise in laboratory markers for thrombin and fibrin generation, to fulminant disseminated intravascular coagulation (DIC) with the formation of microvascular thrombi in various organs [1]. Bleeding, thrombosis, or both may be the presenting clinical features. DIC may contribute to multiorgan failure (MOF) and is associated with a high mortality in both bacterial and nonbacterial disease [2, 3]. Studies of gram-negative sepsis in humans and experimental animals have shown that cytokines play a pivotal role in the activation and regulation of the coagulation cascade, although the interactions are complicated, and the effects are time-dependent and transient [4]. Activation of the coagulation system has also been documented for nonbacterial pathogens (i.e., viruses causing hemorrhagic fevers [HFs] [5, 6], protozoa [malaria] [7, 8], and fungi [9]).