Abstract:To investigate the changes of serum levels of N-terminal pro -brain natriuretic peptide (NT-proBNP) and high mobility group box 1 protein (HMGB1) in the patients with severe pneumonia and their significance in prediction of prognosis. Methods Totally 96 patients with severe pneumonia were divided into survival group (59 cases) and death group (37 cases). In the same period, 40 healthy subjects were selected as control group. The serum levels of NT -proBNP and HMGB1 were measured and the APACHE Ⅱscores were recorded for all severe pneumonia patients on day 1, 3, 5 and 7 after admission,and in the control group on the examination day. Results The serum levels of NT-proBNP and HMGB1 on day 1 in the patients with severe pneumonia were higher than those in the control group (p < 0.05). Compared with the values on day 1, the serum levels of NT-proBNP and HMGB1 and the APACHE Ⅱscores in the survival group decreased on day 3, 5 and 7; the serum levels of NT-proBNP and HMGB1 in the death group decreased on day 3 but increased on day 5 and 7, the APACHE Ⅱscores in the death group increased onday 3, 5 and 7 (p < 0.05). The serum levels of NT-proBNP and HMGB1 and APACHE Ⅱscores on day 1,3, 5 and 7 in the survival group were lower than those in the death group (p < 0.05). Pearson correlation analysis showed that the serum levels of NT-proBNP and HMGB1 in the patients with severe pneumonia were positively correlated with APACHE Ⅱscores (p < 0.05). Conclusions The serum levels of NT-proBNP and HMGB1 in the patients with severe pneumonia increase, and are correlated with the severity and prognosis of the patients. They could be used as adjuvant indicators for assessment of disease and prognosis.