LACC1 and systemic-onset juvenile idiopathic arthritis: Interestingly, Still disease and juvenile dermatomyositis (JDM) have not been commonly associated to single‐gene mutations, except in patients with extremely rare LACC1 deficiencies or JDM mimics with chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE) genotypes.161, 162, 163