Feeling disjointed

Troy, a 26-year-old self-employed farmer, reports that two weeks after a short episode of diarrhoea five months prior, he developed migratory wrist and foot polyarthralgia that has persisted.


He details four hours' morning stiffness with diurnal variability, heel pain and foot swelling, which has greatly limited his ability to perform work tasks. There is no back pain, skin or ocular symptoms, or systemic upset. He reports no extra-articular features of inflammatory rheumatic disease or spondyloarthritis. He has had no unprotected sexual activity. His father had psoriasis.

He had