Onset of vitiligo in a psoriasis patient on ixekizumab.

INTRODUCTION: Vitiligo is an acquired skin disorder clinically characterized by hypopigmentated macules and patches. Psoriasis is a chronic-inflammatory-skin-condition characterized by erythematous-plaques covered with scales particularly over the extensor-surfaces, scalp, and lumbosacral region. Recent major-researches-advancements have significantly expanded our understanding of psoriasis-pathophysiology, resulting in the development of highly effective targeted-therapies, such as anti TNFα, IL-12/23-inhibitors, IL-17-inhibitors, or IL-23-inhibitors. Particularly, ixekizumab, a humanized-monoclonal immunoglobulin-G 4 antibody, specifically binding IL-17A, demonstrated strong efficacy in threating recalcitrant psoriasis. Nevertheless, paradoxical reactions due to IL-17 inhibitors have been described. CASE REPORT: Herein, we report the case of a 53-year-old Caucasian man who obtained complete skin clearance of psoriasis plaques after 16 weeks of ixekizumab treatment together with the appearance of vitiligo patches localized on the facial area. He had never suffered of vitiligo and his family history excluded vitiligo diagnosis. We also could exclude post inflammatory psoriasis hypopigmentation because of absence of facial involvement at baseline. Our experience suggests that vitiligo might be considered a rare adverse effects of anti-IL-17 therapy.