IL-17A in the Psoriatic Patients' Serum and Plaque Scales as Potential Marker of the Diseases Severity and Obesity

Background: Psoriasis is a chronic inflammatory skin disorder often associated with systemic inflammation and metabolic comorbidities, including obesity. Interleukin-17A (IL-17A) plays a key role in the pathogenesis of psoriasis by promoting keratinocyte proliferation and inflammatory responses. Its correlation with disease severity and obesity remains under investigation. This aims to evaluate the levels of IL-17A in the serum and plaque scales of psoriatic patients and assess its potential as a biomarker for disease severity and obesity. Material and Methods: A cross-sectional study was conducted on psoriatic patients of varying severity and body mass index (BMI). IL-17A levels were measured in serum and plaque scales using ELISA. Disease severity was assessed using the Psoriasis Area and Severity Index (PASI), and obesity was evaluated based on BMI. Statistical correlations between IL-17A levels, PASI scores, and BMI were analyzed. Results: According to psoriasis severity, patients with mild disease (n = 30) had the lowest serum IL‑17A levels (34.5 ± 7.6 pg/mL) and plaque IL‑17A levels (92.3 ± 18.4 pg/mg). Those with moderate disease (n = 45) showed higher serum IL‑17A (44.1 ± 9.8 pg/mL) and plaque IL‑17A (118.7 ± 25.3 pg/mg) levels. Patients with severe psoriasis (n = 25) had the highest IL‑17A concentrations, with serum levels of 58.4 ± 10.2 pg/mL and plaque levels of 158.6 ± 28.5 pg/mg. The differences in IL‑17A levels between mild, moderate, and severe groups were statistically significant (p < 0.001 for both serum and plaque measurements). Conclusion: IL-17A levels in serum and plaque scales may serve as a potential biomarker for psoriasis severity and are associated with obesity. Monitoring IL-17A could aid in assessing disease progression and guiding targeted therapeutic strategies.

Keywords:Psoriasis, IL-17A, Serum, Plaque scales, Disease severity, Obesity, Biomarker, Inflammation.