Improvement of psoriatic skin lesions following pirfenidone use in patients with fibrotic lung disease.

Psoriasis is an immune-mediated inflammatory disorder of the skin, characterised by uncontrolled proliferation and dysfunctional differentiation of keratinocytes. In our case series, pirfenidone was administered for the management of fibrotic lung disease and, serendipitously, we noticed remission of coexisting cutaneous psoriatic lesions few months after treatment initiation. Pirfenidone's antifibrotic and immunomodulatory properties have been well studied; yet, not fully elucidated. In line with this, pirfenidone may exert pleiotropic therapeutic effects in other immune-mediated diseases such as psoriasis, while, at the same time, spare immunosuppression-related side effects of current antipsoriatic drugs. Pirfenidone-mediated enhanced absorption of ultraviolet A and ultraviolet B by skin keratinocytes might represent a potential mechanism. The possible role of pirfenidone as an antipsoriatic drug requires large-scale and long-term study.