IL37 and adult-onset Still disease: When the serum IL-37 levels were analyzed with regard to the manifestations of AOSD, the patients who had fever had a higher serum IL-37 level (428.42 ± 291.4 pg/ml) than the patients who did not have fever (165.33 ± 221.06 pg/ml) (P = 0.0003) (Table 3), and the patients who had a skin rash had a higher level (416.33 ± 308.19 pg/ml) than those who did not have a rash (217.60 ± 239.06 pg/ml) (P = 0.0041) (Table 3).