IL18 and rheumatoid arthritis: The serum levels of IL-18 in 67 healthy controls, 145 patients with RA, 6 patients with adult-onset Still's disease, 31 patients with OA and 39 patients with SLE were 159.9 ± 10.9, 299.4 ± 16.1, 6,566.1 ± 2,679.7, 195.5 ± 12.8 and 372.3 ± 32.6 pg/mL, respectively.