[Concept of SIRS and severe acute pancreatitis].

Acute pancreatitis is a potentially fatal disease, the severity of which ranges from a mild edematous form to a severe necrotizing form. Most patients develop systemic inflammatory response syndrome (SIRS), which is induced by proinflammatory cytokines. The cytokine production can be induced by activation of Toll-like receptor. The breakdown products of the pancreatic and peripancreatic tissues by proteases might be the agonists. Cytokines are supposed to be produced as a biological defense system. However, cytokines may often evoke organ failure and/or immunosuppressive state, if they would be produced excessively. To express this complicated pathologic condition, Ogawa proposed a concept of LISIS(local inflammation-induced systemic immunosuppression syndrome). We have to pay attention to such aspects in the management of this disease.