Imaging Insights into the Diverse Manifestations of Psoriatic Arthritis

Abstract

Psoriatic arthritis (PsA) is a chronic inflammatory musculoskeletal disease, with diverse clinical manifestations including psoriasis (Pso) of the skin or nails, in combination with peripheral arthritis, dactylitis (swelling of an entire digit), enthesitis (inflammation at the site where tendons/ligaments attach to the bony surface) or axial disease. PsA is part of the group of rheumatic conditions we refer to as 'spondylarthritis' (SpA), which also includes ankylosing spondylitis, reactive arthritis and arthritis in the context of inflammatory bowel disease, among others. With the use of different imaging techniques such as x-rays, magnetic resonance imaging (MRI) and, in experimental settings, positron emission tomography/computed tomography (PET/CT) we can capture the diverse (sub)clinical disease manifestations of these patients, to advance our understanding of disease pathogenesis, monitor disease activity or to predict treatment response. Although many further steps are needed, the works presented in this thesis show that subclinical disease is common at the enthesis of Pso and SpA patients and that the inflammatory reaction in PsA may also involve non-musculoskeletal organs such as the arterial wall. With the TOFA predict study, study-protocol described in this thesis, we aim to deliver evidence-based imaging predictors of treatment response and learn more on the relevance of subclinical findings on MRI and PET/CT.