CXCL10 and rheumatoid arthritis: The median serum CXCL10 level was 16.92 (IQR 7.01–33.65) pg/ml, in the active PMR group, which was significantly higher than that of 6.26 (IQR 4.54–12.75) pg/ml, in the active RA group (Z =  − 2.974, P = 0.003), and also significantly higher than that of 5.56 (IQR 3.65–13.34) pg/ml, in the remission PMR group (Z =  − 3.670, P < 0.001) and 6.25 (IQR 4.84–8.12) pg/ml (Z =  − 3.662, P < 0.001) in the healthy control group, both of which were statistically significant differences.