Psoriatic arthritis (PsA) is one of the most severe joint diseases. Despite being more prevalent than Rheumatoid Arthritis, affecting more than 1% of the population in Europe and North America, current knowledge on the pathophysicology of PsA is still limited.

In the last years it has become clear that the pathogenic processes, clinical presentation and treatment responses differ fundamentally between PsA and Rheumatoid Arthritis. Nonetheless research specifically dedicated to PsA is rather limited to date, especially when comparing it to the efforts that are undertaken in Rheumatoid Arthritis.

This situation warrants more research in order to better understand the specific features of PsA. The recent arrival of new treatment modalities in psoriasis and also in PsA provides an excellent opportunity to improve our insight into PsA as a disease.