Dermatol Ther (Heidelb). 2026 May 19. doi: 10.1007/s13555-026-01733-x. Online ahead of print.
ABSTRACT
Chronic inflammatory skin diseases (CISDs) such as psoriasis (PsO), atopic dermatitis (AD), and hidradenitis suppurativa (HS) involve both cutaneous and systemic immune dysregulation, whereas commonly used scores rely largely on subjective clinical features and insufficiently reflect underlying inflammatory activity or cardiovascular risk. This review summarizes evidence across three biomarker domains: tissue-level pathways (the Fas/FasL and interleukin (IL)-21/IL-21R), circulating inflammatory mediators, and hematology-derived indices (the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), pan-immune-inflammation value (PIV), derived neutrophil-to-lymphocyte ratio (d-NLR), systemic inflammation response index (SIRI), systemic immune-inflammation index (SII), and aggregate index of systemic inflammation (AISI)) in relation to disease activity, therapeutic response, and cardiometabolic burden. A targeted literature search was performed in PubMed/MEDLINE, Scopus, and the Cochrane Library (January 2000 to November 2025), supplemented by artificial intelligence (AI)-assisted retrieval, manual screening of reference lists, and citation tracking. Studies providing patient-derived clinical or translational data were included and summarized in structured comparative tables. The findings indicate that dysregulated Fas/FasL signaling contributes to keratinocyte apoptosis resistance and chronic epidermal inflammation in PsO and AD, with limited data in HS. IL-21 is elevated in PsO and AD, correlating with clinical severity and epidermal hyperplasia, whereas its role in HS remains unexplored despite the strong Th17 and B-cell signature of the disease. Complete blood count-derived indices demonstrate associations with systemic inflammation and increased cardiometabolic risk, particularly in PsO and HS, yet diagnostic performance varies and methodological standardization is lacking. Taken together, these biomarkers provide insights into local and systemic aspects of disease biology but are not yet validated for clinical use. Integrating tissue-specific mediators, soluble biomarkers, and hematologic indices into multimodal panels may ultimately strengthen precision monitoring of disease activity, treatment response, and cardiovascular risk in CISDs. Prospective, multicenter studies are needed to establish clinically actionable, biomarker-driven strategies that enable more mechanism informed and personalized care.
PMID:42156635 | DOI:10.1007/s13555-026-01733-x