PET imaging in the psoriasis and psoriatic arthritis field: un update

Psoriasis is a chronic autoimmune inflammatory disease that affects skin and nails but may also involve further sites of clinical or subclinical inflammation, including the joints. The aim of this review is to explore the role of PET imaging in psoriasis and psoriatic arthritis, especially in the assessment of joint and systemic inflammation and vascular inflammation, such as aortitis. We conducted an unstructured search of the literature for any studies employing the f [18F]-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG PET/CT) in the assessment of inflammation in patients with psoriasis or psoriatic arthritis. The role of [18F]-FDG PET/CT has been explored, with special focus on potential novel biomarkers, assessment of disease severity, and the imaging monitoring and validation of novel therapeutic strategies, including also future perspectives concerning further PET tracers, such as [18F]fluoride PET imaging. The possibility of the evaluation of inflammation in different sites can be used to evaluate both systemic, articular and periarticular inflammation, giving the possibility of a comprehensive assessment of the patients. The emerging clinical needs for novel biomarkers in the psoriasis field can be potentially supported by novel biomarkers on FDG PET imaging in several research settings but further multicentric trials are needed for the implementation in the clinical practice.