HMGB1 and peritonitis: Consistent with results obtained by immunoblot analysis, HMGB1 levels in PD patients with peritonitis were significantly increased compared to the controls (12.73 versus 5.93 ng/ml, P<0.01) (Fig. 1E), and also significantly higher in patients with Gram-negative peritonitis than those with Gram-positive peritonitis (17.14 ng/ml versus 10.79 ng/ml, P<0.01) (Fig. 1F).