Capillary permeability is a tightly regulated feature of microcirculation in all organ beds; however, in sepsis this feature is fundamentally altered. We previously reported elevated levels of vascular endothelial growth factor and its receptor (fms-like tyrosine kinase-1) in patients with septic shock, then investigated two kinds of angiopoietins in those patients. An enzyme-linked immunoassay was used to measure serum angiopoietin-1 and -2 levels in 12 patients with septic shock who were treated by direct hemoperfusion with a polymyxin B-immobilized fiber column (DHP-PMX). The angiopoietin-1 level was lower in patients with septic shock (7.01 +/- 10.08 ng/mL) than in controls (28.24 +/- 11.61 ng/mL, P < 0.001), but the angiopoietin-2 level was higher in septic shock patients (40.83 +/- 30.13 ng/mL vs. 2.47 +/- 1.78 ng/mL, P < 0.001). Between seven survivors and five non-survivors there was no significant difference in angiopoietin-1 levels before DHP-PMX therapy. During DHP-PMX therapy, however, the angiopoietin-2 level was significantly decreased in survivors (31.52 +/- 26.15 ng/mL vs. 17.32 +/- 22.46 ng/mL, P = 0.035). Moreover, at the end of the therapy, the angiopoietin-1 level was significantly lower in non-survivors (1.14 +/- 1.30 ng/mL vs. 10.43 +/- 13.56 ng/mL, P = 0.042), but the angiopoietin-2 level in non-survivors was significantly higher (70.79 +/- 40.47 ng/mL vs. 17.32 +/- 22.46 ng/mL, P = 0.019). The angiopoietin-2 level may be associated with vascular permeability in septic patients, and angiopoietins may be suitable markers of disease severity and mortality.