Massive Lymphocyte-Mediated Apoptosis during the Early Stage of Pseudopelade

Abstract

The early evolving lesions of the hair follicles are described in pseudopelade, a type of cicatricial alopecia where clues for the diagnosis of lupus erythematosus or lichen plano-pilaris are lacking. A sudden and synchronized cell death of all the cells of the epithelial sheaths of the hair follicles occurs and is associated with a dense infiltration by lymphocytes. The epidermis remains uninvolved. This unique aspect is most probably related to the mechanism of apoptosis. Its intensity and extension are much more pronounced than in lichen planus and in lupus erythematosus. Pathogenesis of at least some cicatricial alopecias could therefore be related to massive apoptosis without evident and close relationship with the classical etiologies, i.e. lichen planus and lupus erythematosus.

Linear hyperpigmentation with extensive epidermal apoptosis: a variant of linear lichen planus pigmentosus?

“…A case of lichen planopilaris, pseudopelade, with a massive apoptosis of the epidermal sheath of the hair follicles has been reported. 12 In pseudopelade, clinical examination of the skin often fails to reveal inflammatory signs. Our cases similarly showed linear pigmentation without an apparent inflammatory sign at their onset.…”

Update on primary cicatricial alopecias

“…Many continue to maintain that pseudopelade of Brocq is distinct clinicopathologically. [173][174][175][176][177][178] Others view it as a variant of certain primary cicatricial alopecias, 66,133,[179][180][181][182] namely, lichen planopilaris and DLE, or alternatively, as the common final stage of several cicatricial alopecias (état pseudopeladique). 183,184 To confuse matters, the term pseudopelade alone is used indiscriminately in the literature to denote both pseudopelade of Brocq and other forms of cicatricial alopecia that simulate it; definition is required each time the term is used.…”

Patterns of cell death: the significance of apoptosis for dermatology

“…EGF infusion induces apoptosis and thus catagen in sheep wool follicles (73). Apoptosis was described in the early stage of scarring alopecia (66) and in alopecia areata (83), and it is the standard response of the follicle to injury by irradiation or eytotoxie drugs (67)(68)(69). If one uses well-defined rodent models (e.g.…”