Role of Granulocyte Elastase in Tissue Injury in Patients with Septic Shock Complicated by Multiple-organ Failure

Abstract

To better understand the role of granulocyte elastase (GE) in mediating tissue injury during sepsis, GE levels were measured in plasma and bronchoalveolar lavage fluid (BALF) in patients with septic shock (n = 16) and hemorrhagic shock (n = 30). Granulocyte elastase levels were compared to levels of alpha 1-protease inhibitor (alpha 1-PI). Results show that although plasma GE-alpha 1-PI complex was initially elevated in patients with hemorrhagic and septic shock, elevations in plasma GE-alpha 1-PI complex (831 +/- 241 micrograms/L) persisted in septic shock patients. alpha 1-Protease inhibitor levels in serum were increased, resulting in an inhibition of serum GE activity. Granulocyte elastase activity in BALF, however, was significantly higher in those patients with septic, as compared to hemorrhagic shock (31.4 +/- 25.8 versus 3.7 +/- 4.0 U/L, respectively). In addition GE levels were compared to other parameters, including respiratory index, blood neutrophil count, and plasma levels of endotoxin, fibronectin, and coagulation factor XIII. Significant correlations were observed between GE-alpha 1-PI and increased endotoxin concentration and decreased fibronectin and coagulation factor XIII levels. Significant correlation was found also between GE activity in BALF and respiratory index. These findings suggest that severe tissue damage occurred in patients with septic shock complicated by multiple-organ failure. Although GE activity appeared to be adequately inhibited by alpha 1-PI in blood, increased GE activity in local tissues, such as lung alveoli, may be responsible for significant local tissue injury during septic shock.