Interleukin-18 and miR-130a in severe sepsis patients with thrombocytopenia

BACKGROUND Thrombocytopenia is one of the most common laboratory abnormalities encountered in patients with severe sepsis. It has been reported that thrombocytopenia is linked to mortality in patients with severe sepsis. However, the mechanism of thrombocytopenia in sepsis is unknown. We hypothesized that inflammatory cytokines and microRNAs (miRNAs) are not only involved in the pathogenesis of sepsis, but also are correlated with thrombocytopenia. PATIENTS AND METHODS Eligible patients with severe sepsis were prospectively recruited and treated at our hospital between June 2012 and May 2014. The miRNA and protein expression of interleukin (IL)-18 and IL-27 were detected by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The expression of miR-130a and miR-150 was detected by TaqMan real-time polymerase chain reaction. RESULTS Sixty eligible patients were divided into two groups: 28 severe sepsis patients with thrombocytopenia and 32 severe sepsis patients without thrombocytopenia. The results demonstrated that the miRNA expression and plasma concentration of IL-18 in severe sepsis patients with thrombocytopenia were higher than those in severe sepsis patients without thrombocytopenia (P=0.015 and P=0.034, respectively), and miR-130a expression was significantly lower in severe sepsis patients with thrombocytopenia (P<0.003). CONCLUSION Our data demonstrate that severe sepsis patients with thrombocytopenia have increased plasma and miRNA expression levels of IL-18 and decreased expression of miR-130a, suggesting that IL-18 and miR-130a might be involved in the pathophysiological process of severe sepsis with thrombocytopenia.