Cicatrising alopecia with perifollicular blue-gray patches is most commonly associated with:

Cicatrising alopecia with perifollicular blue-gray patches is likely to be associated with whitish lesions in buccal mucosa which is characteristic of Lichen planus. Ref: Cicatricial Alopecia: An approach to diagnosis and management, By Vera Price, Paradi Mirmirani, Page 1-5.