Arthritis associated with psoriasis was first described in 1956 by Wright. 1 It was not until
1973, however, that Moll and Wright 2 defined the various clinical phenotypes, including
asymmetric arthritis, enthesitis, dactylitis, and nail disease. The following year, these authors
introduced the concept of spondyloarthritis, a cluster of diseases with shared clinical and
immunogenetic features. 3 Despite these advances, the immunopathogenesis of psoriatic
arthritis (PsA) remained poorly understood, awaiting a more detailed understanding of …