<prompt> A 45-year-old male has multiple grouped vesicular lesions present on the T10 segment dermatome associated with pain The most likely diagnosis is -Herpes zosterDermatitis herpetiformisHerpes simplexScabies  <response>: Ans. is a i.e., herpes zoster Here is a Dd of commonly asked vesico bullous disorders So the crux is -Painful lesions are seen in Herpes infection.Painless lesions are seen in-Dermatitis herpetiformis Pemphigoid Pemphigus Erythema multiformeDermatomal involvement-Herpes zosterItchy lesions-Dermatitis herpetiformisIntraepidermal-Herpes and pemphigusSubepidermal-Dermatitis herpetiformis Pemphigoid Erythema multiforme 