Psoriatic arthritis and psoriasis: differential diagnosis.

Psoriasis frequency ranges from 1 to 3 % in white population, and arthritis occurs in 10-40 % of psoriasis patients, representing a relevant health issue. Psoriatic arthritis (PsA) is an inflammatory arthropathy, associated with psoriasis, in which ocular-, intestinal-, metabolic-, and cardiovascular-related manifestations can variably coexist. In order to favor early PsA and psoriasis diagnosis, it is crucial to rule out other conditions that can resemble the disease and delay appropriate therapeutic approach. Therefore, the aim of this review is to focus on PsA and psoriasis differential diagnosis.