IL6 and juvenile idiopathic arthritis: IL-18: IL-6 in AOSD and JIA indicates that when IL-18: IL-6 > 5000, the probability of AOSD is 100% (11/11); however, when it is <5000, the probability of AOSD is 60% (9/16).[66] In this case, the IL-18: IL-6 was 170,000:12.6 (13,492.1); therefore, it was speculated to be systemic AOSD.