INTRODUCTION
There have been several case reports of pemphigus foliaceus arising in patients with psoriasis vulgaris treated with narrow-band ultraviolet B (NB-UVB) therapy.1 It is thought that treatment with NB-UVB can trigger desmoglein autoantibodies in pemphigus foliaceus by damaging the dermal-epidermal junction.2 Herein, we report a case of juvenile pemphigus foliaceus following NB-UVB therapy in a patient with a history of psoriasis vulgaris.
CASE REPORT
A 16-year-old male with no significant past medical history presented with a 14-month history of pruritic erythematous silver, scaly plaques on his scalp, face, chest, back, and legs sparing mucosal membranes with additional nail pitting. A family history of psoriasis was notable in his father and uncle. A skin biopsy was consistent with psoriasis vulgaris. After failing topical corticosteroid therapy, systemic treatment was initiated with ustekinumab with mild improvement in his psoriasis.
Ustekinumab was discontinued and secukinumab was initiated. However, he showed only slight improvement in his skin lesions following 3 months of secukinumab, which was discontinued. NB-UVB therapy was added for 11 cycles, but he began to progress to erythroderma with diffuse and generalized painful arcuate and polycyclic plaques with excoriations and scaling, and a few blisters that ruptured leaving superficial erosions (Figure 1). No mucosal lesions or joint pains were present. NB-UVB therapy was discontinued, and he was started on
prednisone 60 mg daily. A repeat skin biopsy demonstrated an intracorneal split and direct immunofluorescence showed granular immunoglobulin G (IgG) deposition consistent with pemphigus foliaceus. Additionally, his blood was positive for anti-desmoglein-1 antibodies. Considering the adverse effects of
