10% of PsA is PsA Sine Psoriasis - how to differentiate from seroneg RA? PsA sine PsO pts have peripheral arthritis, no skin dz, but may have axial sxs, +Family Hx or nail psoriasis, dactylitis, enthesitis, DIP involvement. https://t.co/TijVEc9Uw7 https://t.co/W6C1CTYbA9