CD74 and spondylitis: Median CRP (IQR) values were higher (3.9 (1.0; 8.0) vs. 2.4 (1.0; 7.2)) and the impairment of spinal mobility according to the median BASMI (Bath Ankylosing Spondylitis Metrology Index, IQR) more severe in patients with elevated anti-CD74 Abs (1.3 (0.0, 3.0) vs. 1.0 (0.0, 2.0)).