BI35 A case of dupilumab-induced scalp psoriasis and review of the literature

Abstract Dupilumab is a monoclonal antibody that inhibits the interleukin (IL)-4 and IL-13 receptor subunit. It has been approved for the treatment of moderate-to-severe atopic dermatitis (AD), with a good safety profile. Recently, the literature has reported dupilumab-induced psoriasis, primarily in patients with AD. Herein, we present a unique case of dupilumab-induced psoriasis and psoriasiform eruption in an adult patient with AD during treatment with dupilumab. A 32-year-old man presented at our dermatology department with AD that had been present since childhood, associated with asthma and allergic rhinitis. The AD was ineffectively controlled by topical steroids, ultraviolet therapy and abrocitinib. He was trialled on methotrexate (up to 12.5 mg per week), which helped control his eczema but was discontinued because of deranged liver function. He continued to develop severe recurrent flare-ups requiring treatment with short-term oral prednisolone and then ciclosporin. He was commenced on dupilumab (300 mg subcutaneously every 2 weeks), resulting in complete remission of AD. However, he developed well-defined, erythematous plaques with yellow scale on his scalp, forehead, eyebrows and ears after about 4 months, with worsening hair loss, which had a significant impact on his quality of life. He had no personal or family history of psoriasis. Dupilumab was discontinued due to increasing hair loss and patient anxiety. He was started on topical steroid for the scalp psoriasis with complete clearance. His AD is being managed with lebrikizumab. The temporal relationship between the initiation of dupilumab treatment and the onset of psoriasis in our patient suggests that dupilumab may have contributed to the development of the psoriatic lesions. Forty-seven cases of dupilumab-associated psoriasis have been reported in the literature, including 37 adults and 10 children (Su Z, Zeng YP. Dupilumab-associated psoriasis and psoriasiform manifestations: a scoping review. Dermatology 2023; 239: 646–57). The mean time to onset of de novo psoriasis after dupilumab treatment was 4.3 months (range 1–18). Plaque psoriasis seems to be the most common variant and affects the extremities, trunk and scalp. About 11 cases of scalp psoriasis developing in patients on dupilumab have been reported (Beaziz J, Bouaziz JD, Jachiet M et al. Dupilumab-induced psoriasis and alopecia areata: case report and review of the literature. Ann Dermatol Venereol 2021; 148: 198–201). Hypothetically, the blockade of the T helper (Th)2 response with dupilumab by targeting the IL-4/IL-13 signalling pathway could result in a shift towards a Th1/Th17 phenotype, leading to an inflammatory cytokine cascade and eventually psoriatic skin plaques, as described in this report. Dermatologists should be aware of psoriasis as a potential adverse event with dupilumab.