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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Darrier's sign is seen in -
assistant
The correct answer is  Ans. is 'b' i.e., Urticaria pigmentosao Urticaria pigmentosa is a familial cutaneous disorder characterised by generalised distribution of red brown macules,o Each lesion represents a collection of mast cells in the dermis with hyperpigmentation of overlying epidermis,o The most characteristic features is that these lesions urticate on scratching.o Light scratching with the point of forceps or rounded tip of a pen or even rubbing causes these mast cells to degranulate leading to localized urticaria (become red swollen and enlarged) - Darrier's Sign Extensive release of histamine from mast cell degranulation may result in - Headache, flushing diarrhea and pruritis.