The psoriatic disease concept includes psoriasis (PsO) and psoriatic arthritis (PsA). PsO is a chronic relapsing inflammatory skin disease characterized by scaling lesions, typically localized on the extensor surfaces and the trunk. PsA is a chronic inflammatory skeletal disease associated with PsO. PsA has heterogeneous clinical manifestations with some forms clearly linked to the spondyloarthritis (SpA) concept. PsA is a common disease, but many aspects of this disorder remain enigmatic. Lingering questions focus on the precise relationship between manifestations of joint and skin disease and on molecular and cellular mechanisms of inflammation and immunity that lead to the cardinal symptoms. During the last year new insights have been developed to shed further light on some of the enigmatic aspects of the disease. In addition to biological therapies targeting tumor necrosis factor, new treatments are shown to be effective for skin or joint disease. These include strategies directed against interleukin-17 and interleukin-23 but also non-biologic targeted therapies such as apremilast. Long-term data provide further insights into the management of the disease. In this regard, increased evidence for the necessity of treating comorbidity strongly supports the concept of a holistic disease management. Progress in imaging illustrates some key anatomic and pathophysiological concepts that help understanding the development, progression and consequences of the disease. Finally basic and translational science approaches identified key cell types and cytokines involved in the disease and link out towards the microbiome. Large investments into genetics of psoriatic arthritis finally seem to pay off by identifying factors that are specifically linked to the joint disease.
Disclosure of Interest R. Lories Grant/research support from: Abbvie, Boehringer Ingelheim, Celgene, Pfizer, Consultant for: Abbvie, Boehringer Ingelheim, Celgene, Janssen, MSD, Pfizer, UCB