abnormal circulating interleukin-18 level increased circulating interleukin-18 level MP:0008635 MPheno.ontology increase in the amount in the blood of a cytokine which enhances the cytotoxic activity of NK cells and cytotoxic T-cells and appears to play a role both as neuroimmunomodulator and in the induction of mucosal immunity increased circulating IFN-gamma inducing factor level increased circulating IL-18 level increased circulating IL18 level increased circulating interferon-gamma inducing factor