A 85 year old woman with Nikolsky sign–ve, blisters on thigh & trunk, lesions come on & off. What is the cause –
In this question :-


Age → 85 year
Blisters on lower body (thigh & trunk)
Nikolsky's sign negative


Amongst the given options only pemphigoid (bullous pemphigoid) full fills these criteria.
Pemphigus vulgaris
Pemphigoid
Lichen planus
Dermatitis herpetiformis