Using the JIA core set criteria in defining active and inactive disease, Holzinger et al. found S100A8/9 levels to be predictive of flare in sJIA patients, and that a cut-off of 740 ng/ml was 92% sensitive and 88% specific in diagnosing a flare in sJIA patients [14]. Here, S100A8 is linked to juvenile idiopathic arthritis.