Convergence of Psoriatic Arthritis and Hyperuricemia: A Review of Emerging Data from This New Concept Called “Psout”

This review examines the concept of “psout”, an overlap syndrome of hyperuricemic psoriatic arthritis (HU-PsA) and co-existing gout and PsA. The manuscript explores its epidemiology, pathophysiology, clinical implications, and treatment strategies, focusing on emerging data since its first description in 2020. The psout concept is sustained by shared inflammatory and metabolic pathways between gout and PsA, contributing to a broad spectrum of phenotypes and moderate-to-severe clinical manifestations. Monosodium urate crystals and hyperuricemia are central to this overlap, influencing cytokine production, keratinocyte activation, and immune responses, being able to activate both innate and acquired immunity. Clinical management is complex due to diagnostic challenges and therapeutic considerations not yet implemented in international recommendations. Emerging data from clinical trials underscore the significance of hyperuricemia in worsening PsA outcomes while highlighting the potential of personalized treatments. Future research into shared pathophysiological mechanisms, the accurate description of the diversity of phenotypes, innovative imaging assessments, and therapeutic strategies could provide insights into the interplay of these two conditions and enhance patient outcomes.