Significance of erythrocytes phosphatidylserine exposure on occurrence of anemia in sepsis

Objective To investigate the role of phosphatidylserine(PS)exposure of erythrocytes in the development of anemia in sepsis patients.Methods A self-control study was conducted.Thirty sepsis patients admitted to intensive care unit(ICU)were enrolled.Peripheral venous blood was collected on 1 day and 7 days after ICU admission,and hemoglobin(Hb)concentration was examined routinely.A flow-cytometric assay based on Annexin V/ propidium iodide(Annexin V/PI)was used to measure the PS exposure of erythrocytes.The relationship between PS exposure and Hb concentration was analyzed.Results Hb concentrations in 30 sepsis patients at 7 days after ICU admission were significantly decreased compared with those of patients at 1 day(g/L:81.59±3.31 vs.121.90±3.34,t=8.570,P=0.000),but the percentage of PS exposure of erythrocytes was significantly higher[(17.19 ±1.35)％ vs.(7.87±0.83)％,t=-6.557,P=0.000].An inverse correlation was found between percentage of PS-positive RBCs and Hb concentration by Pearson analysis(r=-0.838,P=0.000).Conclusions The percentage of PS exposure in erythrocytes is significantly increased in sepsis,and it might contribute to the development of anemia in sepsis patients during hospital stay.The more severe the anemia,the higher the PS in erythrocytes. Key words: Sepsis; Erythrocytes; Phosphatidylserine; Anemia