TNF and arthritic joint disease: Alivernini et al. analyzed the histological characteristics of inflammatory infiltrate in the synovia and in the gut of IBD patients who developed paradoxical arthritis during anti-TNFα therapy, showing similar immune cells (CD68+, CD3+, CD117+, and CD20+) in both tissues; they also confirmed that swapping to an anti-IL23 may be more effective than switching to a different anti-TNFα to treat such extraintestinal disorders [90].