Serum calcitonin gene-related peptide and neuropeptide Y levels in seborrheic dermatitis: comparison with healthy controls and correlation with disease severity

BACKGROUND: Seborrheic dermatitis (SD) is a chronic inflammatory skin disorder influenced by factors such as Malassezia colonization, sebaceous gland activity, immune dysregulation, and neurogenic inflammation. Neuropeptides like calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY) can modulate disease activity, while psychological stress may play a role in disease onset and flare-ups. OBJECTIVES: To evaluate serum CGRP and NPY levels in patients with SD, investigate their relationship with disease severity, and explore potential links with perceived stress. METHODS: In this cross-sectional case-control study, 51 SD patients and 40 age- and sex-matched healthy controls were included. Disease severity was assessed using the Seborrheic Dermatitis Area and Severity Index (SDASI), and stress was evaluated with the Perceived Stress Scale-14 (PSS-14). Serum CGRP and NPY levels were quantified using Enzyme-Linked ImmunoSorbent Assay (ELISA). ROC analyses indicated good performance in distinguishing moderate-severe disease. PSS-14 scores were higher in SD patients than in controls, but no significant relationship was observed between neuropeptides and disease severity. CONCLUSIONS: Increased serum CGRP and NPY levels in moderate-severe SD compared to mild SD, along with their strong correlation with disease severity, suggest a possible role for neuropeptide-mediated neurogenic inflammation in SD pathogenesis. Although these neuropeptides are not specific to SD, they may serve as potential biomarkers of disease activity. Larger, multicenter cohort studies are needed to confirm their generalizability across populations and comorbidities.