Assessment of YKL-40 as a Potential Biomarker of the Disease Severity in Psoriatic Patients with or without Psoriatic Arthritis Treated with Methotrexate

Abstract

soriasis is an inflammatory skin disease that affects up to 2-3% of the worldwide population. Its pathogenesis is complex and involves a wide variety of processes, including epidermal hyperproliferation, activation of the immune and inflammatory pathways or dermal angiogenesis. YKL-40, a member of 'mammalian chitinase-like proteins', is secreted by macrophages, neutrophils, chondrocytes, endothelial-, vascular smooth muscle-, and cancer cells. High serum YKL-40 is related to conditions of increased tissue remodelling, cancer, and inflammation. The current study is a prospective interventional clinical study, conducted on 40 patients divided into 2 equal groups; group I had psoriasis only while group II had psoriasis with psoriatic arthritis. All patients in our study received methotrexate and folic acid on a weekly basis. The effect of methotrexate on the improvement of the disease was assessed by PASI and DAPSA scores for psoriasis and psoriatic arthritis, respectively. We measured YKL-40 before treatment and at week 12 after treatment We found that methotrexate could improve the PASI scores in all patients and its effect was more noted in patients with psoriasis more than in patients who developed psoriatic arthritis. We observed that methotrexate could also improve the psoriatic arthritis as seen in DAPSA score drop after the treatment course.