A case of follicular traction urticaria
A 20-year-old woman presents with a 3-month history of multiple pruritic follicular urticarial papules that erupt bilaterally on her lower extremities within 30 minutes of shaving with a wet straight razor. These resolve spontaneously within 2 hours. They do not occur when shaving her axillae and occur irrespective of creams or straight razors used. She has no personal or family history of urticaria or angioedema.

She denies taking any medications or supplements. A complete physical examination, excluding pelvic and rectal, is normal. Repeated stroking of the skin with a tongue depressor on the anterior aspect of her thighs and legs does not reproduce these lesions. A clinical diagnosis of follicular traction urticaria (FTU) is made. The patient is started on cetirizine 10 mg daily with rapid resolution of the problem. Physical urticaria is a subgroup of chronic urticaria that is elicited by a specific external trigger.

This can include a hot or cold environment, pressure, vibration, sunlight, and water. FTU, is a rare form of physical urticaria in which lesions are triggered by skin traction. Traction with an external maneuver leads to tension on or around hair follicles, likely stimulating perifollicular mast cells Although rare, follicular traction should be considered among physicians when evaluating urticaria.

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