Dynamic changes of plasma interleukin-18 level in patients with hemorrhagic fever with renal syndrome

WANG Jun-ning; GUO Wei-juan; DU Hong; YU Hai-tao; JIANG Wei; BAI Xue-fan; WANG Ping-zhong

Abstract：Objective To measure the plasma level of interleukin (IL)-18 in patients with different phases and clinical types of hemorrhagic fever with renal syndrome (HFRS), and to investigate the correlation between IL-18 and the progression of HFRS so as to pro-vide evidence for the study of HFRS pathogenesis. Methods Totally 145 plasma samples were collected from 81 patients with different clinical types and different phases of HFRS, who were hospitalized in Tangdu Hospital from Oct. 2011 to Jan. 2014, and plasma samples from 15 healthy volunteers selected as controls (the control group) were collected as well. The plasma IL-18 level was measured using en-zyme-linked immunosorbent assay, and the correlations between IL-18 and other indicators were analyzed. Results Plasma IL-18 level began to rise at febrile stage of HFRS, reached the peak at oliguria stage, and began to decline at diuresis stage, but still higher than that of the control group. The plasma IL-18 level in patients with different clinical types of HFRS displayed a similar trend, that in patients at acute phase higher than that in patients at convalescent phase and that in the control group, and that in patients at convalescent phase higher than that in the control group, especially in severe/critical patients. Spearman correlation analysis indicated that the IL-18 level was positively correlated with WBC and BUN, and negatively correlated with PLT in HFRS patients. Conclusions Plasma IL-18 level is closely correlated with disease severity and progression in HFRS patients. Inhibition of IL-18 expression may alleviate the im-mune-mediated pathological injury in HFRS patients.