CRP and bacterial arthritis: Kunnamo et al. (1987) were the first to propose predictive criteria for distinguishing between septic arthritis (of any joint) and juvenile arthritis in children using univariate and multivariate logistic regression analyses based on clinical predictors (fever) and biological predictors, such as ESR, serum WBC count, C-reactive protein (CRP), and immunoglobulin G and antinuclear antibodies [18].