Hair Whitening in a Patient with Psoriasis on Adalimumab Reversed After Switching to Ixekizumab

The document reports the case of a 40-year-old man with an 18-year history of psoriasis and psoriatic arthritis who experienced hair whitening while being treated with the anti-TNF-α agent adalimumab. Despite initial improvement in his psoriasis symptoms, the patient developed whitening of scalp and facial hair, which was diagnosed as vitiligo. Laboratory tests also revealed new-onset autoimmune thyroiditis. After the loss of efficacy of adalimumab and worsening of psoriasis and psoriatic arthritis, the patient was switched to ixekizumab, an anti-IL-17A agent. This resulted in rapid improvement of psoriasis symptoms and, after 3 months, repigmentation of the vitiligo-affected hair, which continued to improve at 9 and 18 months. The case suggests that while anti-TNF-α agents may induce vitiligo, treatment with an anti-IL-17A agent like ixekizumab can resolve both psoriasis and vitiligo. The document discusses the complex interplay of inflammatory mediators in skin diseases and the potential for biologic therapies to cause paradoxical reactions by disrupting immune balances.