Lichenoid Dermatoses Induced by Phototherapy (For Professionals)

Lichenoid Dermatoses Induced by Phototherapy (For Professionals)

Mandy WM CHAN, Joyce SS Lee, Colin TS THENG, SH CHUA, BH ONG, Hazel H OON. Narrowband UVB-induced Lichen Planus Pemphigoides

National SKin Centre, Singapore

“Lichen Planus Pemphigoides (LPP) is a rare acquired autoimmune disease characterized by the evolution of subepidermal blisters on normal skin and that affected with Lichen PLanus. We describe a case of lichen planus pemphigoides in a 54-year-old Chinese woman. The patient presented initially with scaly psoriasiform plaques and was diagnosed to have guttate psoriasis. She was treated with narrowband ultraviolet (NBUVB) therapy twice weekly. Within a month of starting phototherapy, she experienced a flare up of her skin lesions with a generalized eruption of violaceaous papules, tense bullae over the lower limbs as well as Wickham’s striae over the buccal mucosa. Histology of the violaceous papule over the abdomen revealed interface dermatitis, while the specimen from a blister showed a subepidermal bulla with linear deposition of IgG and C3 along the basement membrane zone. A diagnosis of LPP was made on clinicopathological grounds. The patient subsequently  responded well to oral prednisolone at a dose of 0.5 mg/Kg/day. This is the first case report of a NBUVB alone in unmasking LPP.”