Serum YKL-40 in patients with psoriasis vulgaris treated by narrow-band UVB phototherapy.

Psoriasis is a common chronic and immune-mediated inflammatory skin disease. This study aimed to investigate the serum levels of Chitinase-3-like protein 1 (YKL-40) in patients with psoriasis vulgaris before and after narrow-band ultraviolet B (NB-UVB) phototherapy. This study was designed as a cross-sectional case-control.