Effect of narrow-band ultraviolet B phototherapy, methotrexate, and combined narrow-band ultraviolet B phototherapy with methotrexate on serum cathelicidin and vitamin D in patients with psoriasis vulgaris.

Objective: This study aimed to evaluate the efficacy of narrow-band ultraviolet B (NB-UVB) phototherapy, methotrexate, and combined NB-UVB phototherapy with methotrexate in the treatment of psoriasis vulgaris and to assess their effects on serum cathelicidin and vitamin D.

Methods: This study was conducted on 60 patients with psoriasis vulgaris. They were divided into three groups (20 patients each); Group (A) was treated with NB-UVB phototherapy. Group (B) was treated with methotrexate. Group (C) was treated with combined NB-UVB phototherapy with methotrexate. Patients were assessed with Psoriasis Area and Severity Index (PASI score), serum cathelicidin and vitamin D at the first visit and after three months of treatments.

Results: The highest mean PASI score percent improvement was reported in the combined NB-UVB phototherapy with methotrexate (92%). There was a significant increase in serum vitamin D after treatments with NB-UVB phototherapy and combined NB-UVB phototherapy with methotrexate ( < .001). There was a significant decrease in cathelicidin after three months of treatment with combined NB-UVB phototherapy with methotrexate ( < .01).

Conclusion: This study could contribute to the hypothesis considering the role of cathelicidin and vitamin D in the pathogenesis of psoriasis. The combined NB-UVB phototherapy with methotrexate had the highest clinical improvement of psoriasis vulgaris.