Narrowband UVB-induced lichen planus pemphigoide.
Lichen planus pemphigoides (LPP) is an autoimmune disease characterised by evolution of subepidermal blisters on normal and lichen planus affected skin. We describe a case of LPP in a 54-year-old Chinese woman. The patient presented with psoriasiform plaques and was diagnosed with guttate psoriasis. Narrowband ultraviolet B (NBUVB) therapy was commenced, and she experienced a generalised eruption of violaceous papules, bullae over the lower limbs, and Wickham's striae over the buccal mucosa. Histology from a plaque revealed interface dermatitis, while a specimen from a blister showed subepidermal bulla. Direct immunofluorescence showed linear deposition of IgG and C3 along the basement membrane. A diagnosis of LPP was made on clinicopathological grounds. This is the first case report of NBUVB alone in unmasking LPP. In this case report, we describe the pathological mechanism of NBUVB in the development of LPP and key features distinguishing LPP from bullous lupus erythematosus, bullous lichen planus, bullous pemphigoid, and psoriasis.
National Skin Centre, Singapore.
Wai Man
WM
Mandy Chan
National Skin Centre, Singapore.
Joyce Siong See
JS
Lee
National Skin Centre, Singapore.
Colin Seng
CS
Thiam Theng
National Skin Centre, Singapore.
Sze Hon
SH
Chua
National Skin Centre, Singapore.
Hazel Hwee
HH
Boon Oon
bullous pemphigoid; lichen planus; lichen planus pemphigoides; narrowband UVB; psoriasis.