Phenotypic switch to eczema in patients receiving biologics for plaque psoriasis: a systematic review

The use of biologic therapies for the treatment of chronic plaque psoriasis has been linked to the development of atopic eczema, amongst other cutaneous adverse events. This can cause diagnostic confusion and create difficulty in the management of patients with plaque psoriasis. The main objective of this systematic review was to review all cases of eczema, including atopic eczema, reported in patients treated with biologics for chronic plaque psoriasis. PubMed, Medline and Embase databases were used to identify studies reporting eczema in patients treated with biologic therapy for chronic plaque psoriasis. A total of 92 patients were identified from 24 studies, with patients treated with either: adalimumab; etanercept; infliximab; ixekizumab; secukinumab; or ustekinumab. Factors common to some reported cases include: a prior history of atopy; eosinophilia; raised serum immunoglobulin E. Twenty-three had documented treatment outcomes; 14 had biologic therapy discontinued or switched. Management strategies included topical or oral corticosteroids, and treatment with alternative systemic agents such as ciclosporin or apremilast. This adverse event occurred in 1.0-12.1% of patients within trial data and observational studies. This review demonstrates that there are consistent reports of a switch to an atopic eczema phenotype from psoriasis in patients taking biologics inhibiting tumour necrosis factor alpha and the interleukin (IL)-17/IL-23 axis. The majority stopped the implicated biologic, but conservative management was successful in some cases. Those with an atopic diathesis may be more at risk. Elucidation of mechanisms and risk factors would contribute to optimal therapy selection for individual patients.