Case Number : Case 2374 - 30 July 2019 Posted By: Uma Sundram

Hyperkeratosis, atrophy of prickle cell layer, hydropic degeneration of basal cells, upper dermal edema and lymphocytic infiltrate in the dermis indicate linear extragenital lichen sclerosus et atrophicus.

I don't know if this lesion could clinically fit, but...what about a Necrolytic Migratory Erythema? 

image 1 and 2 shows epidermal necrosis, with intraepidermal bulla with foci of epidermal parakeratosis.  we see vacuolar changes in basal cell layer. there is  dermalperivascuar inflammation

blistering eruption intraepidermal with foci of epidermal necrosis-with sparse dermal inflammation. not able to appreciate any MNGCs

?drug eruption

? any external application

 Paederus dermatitis acute because it is linear

Great list of possibilities. The lesion was acute, linear and unilateral. We also suggested irritant contact dermatitis and linear lichen striatus. Necrolytic migratory erythema is a great suggestion, as is linear LS. The unusual nature of the lesion is its erosion. The clinician will follow over time.

I'd also suspect dermatitis artefacta or at least some external factor. Linear can be a clue.