We evaluated the predictive value of inflammatory state, age and diagnosis of IIM on serum levels of YKL-40 and elucidated that CRP has predictive value on YKL-40 serum levels in IIM patients (P = 0.038) which is according with a cross-sectional study and systematic review published by Cui and et. al. In addition, age and the IIM diagnosis (P = 0.008 and P = 0.001, respectively) showed to be powerful predictors on YKL-40 serum levels24. The gene discussed is CHI3L1; the disease is acquired idiopathic inflammatory myopathy.