Perifollicular Scaling and Possible Diagnoses

Does perifollicular scaling mean lichen planopilaris is my diagnosis?

I’ve selected this question below for this week’s question of the week. It allows us to review some concepts in the diagnosis of lichen planopilaris.

Question

I have a challenging case. One doc thinks I have lichen planopilaris (LPP) and one does not. The first doc saw scaling and did a biopsy and thinks I have LPP. The second doctor does not think I have LPP and feels a biopys is not needed at all.

Is the perifollcilar scale enough to make you want to do a second biopsy?

Answer

Thanks for the question. In general, the answer to your question is no - perifollicular scale in and of itself does not necessarily mean the diagnosis is LPP. Perifollicular scaling is non-specific and seen in many conditions. I would do a biopsy if I am not 100 % sure this is LPP or I am not 100 % sure this is not LPP.

Generally, a really good history and really good trichoscopic examination gets one to the diagnosis and a biopsy is not even needed.

Now that you have one biopsy the key is to make sure all the information is extracted from that tiny biopsy before punching more holes in the scalp. If there is loss of sebaceous glands and clear lichenoid change or necrotic keratinocytes on biopsy AND an experienced doc thinks it’s LPP, then it’s probably LPP. No more biopsies needed. End of story.

Now if there is no loss of sebaceous glands and no real findings in the biopsy of LPP AND an experienced doc thinks it’s really and truly LPP, then a second biopsy is probably going to be needed.

Perifollicular scale is seen in LPP but it’s also seen in a zillion conditions including LPP, FFA, dandruff, seborrheic dermatitis, psoriasis, fungal infections, discoid lupus, dermatomyositis, contact dermatitis …. and more! Perifollicular scale with destruction of the normal nice architecture of the scalp hair follicle design is suggestive of LPP especially when patches of scarring are seen and there is itching and burning and redness. But random scaling does not mean much.

In the image below, I’ll show two examples of scaling. One in a patient with LPP and one in a patient with dandruff. Both have perifollicular scaling.

Two examples of hairs with perifollicular scaling. In the image on the left, mostly single hairs are seen and the process of hair loss here is destructive in nature. In the image on the right, a range of thick and thin hairs are seen and the scalp is not red. There is a single hair with scale here and it represents dandruff or non specific scaling in a patient with androgenetic alopecia.

Also - in the early stages of LPP you sure don’t see scarring. That’s under the scalp and the whole reason we jump on treating LPP as early as possible is to limit the hair loss and limit the amount of scarring that ever gets seen.