Changes of monocyte human leukocyte antigen-DR expression as a reliable predictor of mortality in severe sepsis

In this prospective observational study, mHLA-DR was measured by flow cytometry in peripheral blood from 79 adult patients with severe sepsis. mHLA-DR levels were determined on day 0, 3, 7 after admission to the surgical intensive care unit (SICU) with a diagnosis of severe sepsis. ΔmHLA-DR3 and ΔmHLA-DR7 were defined as the changes in mHLA-DR value on day 3 and day 7 compared to that on day 0. Data were compared between 28-day survivors and non-survivors. Receiver operating characteristic (ROC) curves were plotted to measure the performance and discriminating threshold of ΔmHLA-DR3, ΔmHLA-DR7, ΔmHLA-DR7-3, mHLA-DR0, mHLA-DR3 and mHLA-DR7 in predicting mortality of severe sepsis.ROC curve analysis showed that ΔmHLA-DR3 and ΔmHLA-DR7 were reliable indicators of mortality in severe sepsis. A ΔmHLA-DR3 value of 4.8% allowed discrimination between survivors and non-survivors with a sensitivity of 89.0% and a specificity of 93.7%; similarly, ΔmHLA-DR7 value of 9% allowed discrimination between survivors and non-survivors with a sensitivity of 85.7% and a specificity of 90.0%. Patients with ΔmHLA-DR3 ≤4.8% had higher mortality than those with ΔmHLA-DR3 > 4.8% (71.4% vs. 2.0%, OR 125.00, 95% CI 13.93 to 1121.67); patients with ΔmHLA-DR7 ≤9% had higher mortality than those with ΔmHLA-DR7 > 9% (52.9% vs. 2.0%, OR 54.00, 95% CI 5.99 to 486.08). The mean change of mHLA-DR significantly increased in the survivor group with the passage of time; from day 0 to day 3 and day 7, changes were 6.45 and 16.90 (P < 0.05), respectively.The change of mHLA-DR over time may be a reliable predictor for mortality in patients with severe sepsis.Severe sepsis is an important cause of admission to intensive care units (ICUs) throughout the world and is characterized by high mortality in adults [1-4]. But the pathogenesis of sepsis is still not clear. Previous reports suggest that the depression of the immune system may contribute to the severity of sepsis. Although the mechanistic and molecular