Serum YKL ‐40 and IL 17 in Psoriasis: Reliability as prognostic markers for disease severity and responsiveness to treatment

Background YKL-40, a mammalian chitinase 3- like protein that was associated with multiple inflammatory and immune diseases. Previous studies have suggested a role for YKL-40 in psoriasis based on its significantly higher levels in the serum of psoriatic patient compared to healthy controls. Aim The aim of this study was to determine the correlation between serum YKL-40, psoriasis severity using PASI score and serum levels of IL-17 before and after narrow-band UVB therapy. Methods 28 patients with moderate to severe plaque psoriasis, as defined by PASI scores, were enrolled in this prospective cohort study. All cases received NB-UVB phototherapy twice weekly for three month. Serum YKL-40 and IL-17 levels were evaluated before and after three months of treatment. Clinical photographs were taken both at baseline and after three month. Results There was a statistical positive correlation between serum levels of YKL-40 and serum IL-17 levels as well as PASI score in patients with moderate to severe psoriasis before and after treatment. Conclusion YKL-40 represents a reliable marker for psoriasis severity estimated by PASI and positively correlated with IL 17 as an inflammatory marker in psoriasis. This article is protected by copyright. All rights reserved.