A 40 year old male developed persistant oral ulcers followed by multiple flaccid bullae on trunk and extremities. Direct immunofluorescence examination of a skin biopsy showed intercellular IgG deposits in the epidermis. The most probable diagnosis is:
Pemphigus vulgaris
Bullous Pemphigoid
Bullous Lupus erythematosus
Epidermolysis bullosa acquisita
It is an autoimmune intraepidermal blistering disease due to antibodies against desmoglein 3. It begins as painful oral erosions followed by flaccid blisters on the trunk, face, scalp. Ref: Current Literature Dermatology By Pasricha, Pages 197, 202; Rook's Textbook of Dermatology, 8th Edition.