Patterns of Mucin Deposition in Lichen Planopilaris: A Journey From Follicular "Bubbles" to Perifollicular Fibroplasia.

Lichen Planopiolaris (LPP) is a scarring alopecia characterised by a perifollicular lymphoid cell infiltrate at the level of the infundibulum and isthmus. While perifollicular mucinous fibroplasia is an established finding in LPP, intrafollicular mucin deposition has not been previously reported. We describe two cases with this histopathology and suggest it may represent a helpful clue to the diagnosis of LPP, in the appropriate clinical setting.