Large-scale serum analysis identifies unique systemic biomarkers in psoriasis and hidradenitis suppurativa

Background Hidradenitis suppurativa (HS) is now recognized as a systemic inflammatory disease, sharing molecular similarities with psoriasis. Direct comparison of the systemic inflammation in HS with psoriasis is lacking. Objectives To evaluate the serum proteome of HS and psoriasis, and to identify biomarkers associated with disease severity. Methods In this cross-sectional study, 1536 serum proteins were assessed using the Olink Explore (Proximity Extension Assay) high-throughput panel in patients with moderate-to-severe HS (n = 11), patients with psoriasis (n = 10) and age- and body mass index-matched healthy controls (n = 10). Results HS displayed an overall greater dysregulation of circulating proteins, with 434 differentially expressed proteins (absolute fold change >= 1 center dot 2; P <= 0 center dot 05) in patients with HS vs. controls, 138 in patients with psoriasis vs. controls and 503 between patients with HS and patients with psoriasis. Interleukin (IL)-17A levels and T helper (Th)1/Th17 pathway enrichment were comparable between diseases, while HS presented greater tumour necrosis factor- and IL-1 beta-related signalling. The Th17-associated markers peptidase inhibitor 3 (PI3) and lipocalin 2 (LCN2) were able to differentiate psoriasis from HS accurately. Both diseases presented increases of atherosclerosis-related proteins. Robust correlations between clinical severity scores and immune and atherosclerosis-related proteins were observed across both diseases. Conclusions HS and psoriasis share significant Th1/Th17 enrichment and upregulation of atherosclerosis-related proteins. Despite the greater body surface area involved in psoriasis, HS presents a greater serum inflammatory burden.

Automated summary

Hidradenitis suppurativa (HS) and psoriasis share significant similarities in Th1/Th17 enrichment and upregulation of atherosclerosis-related proteins, with HS patients exhibiting a greater serum inflammatory burden despite psoriasis involving a larger body surface area.