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What is A man presents with bullous lesions on his face, armpit, and chest. He initially had them only in his mouth. They appear round and oval with serous fluid and some are "flabby." When pressure is applied to the lesion, the fluid spreads laterally. A clinical diagnosis of pemphigus vulgaris (PV) is made. (See Figure below) Which of the following is the usual age of onset for this condition? and explain in detail?
PV is most common from 40 to 60 years of age, whereas bullous pemphigoid is seen most frequently after the age of 80. Dermatitis herpetiformis is most common in the age group from 30 to 40, but has a wide age range.