Case Number : Case 2309 - 23 April 2019 Posted By: Dr. Richard Carr

Fixed drug reaction?

interface changes with apoptotic bodies in papillary dermis with pigment incontinence with superficial and mid dermal perivascular lymphocytic infiltrate

interface dermatitis with vacuolar alteration-FDE

Mostly yes by CPC, FDE

Interface dermatitis with superficial and medium perivascular infiltrate. 

Agree. Mostly Fixed Drug Eruption.

Benign lichenoid keratosis.

Lichen planus-like keratosis

The size is a bit small and the duration a bit too prolonged for it to be a fixed drug eruption. Moreover, there's acanthosis and patchy hypergranulosis. I would prefer LPLK over FDE. 

Found this https://pdfs.semanticscholar.org/7025/950f25d85a224937e5825212b6b6436a99a4.pdf

Great, Vincenzo, you are probably right!

Brilliant!  I reported it as a lichen planus-like keratosis (lichenoid keratosis) with ("true") bland melanocytic nests of doubtful clinical significance. May be a reaction to solar lentigo etc.  Thanks for the reference - I was hoping you would follow this literature to it's conclusion. I was always a bit upset that MelanA was given a bad rap, for me it's been a wonderful marker and I'd never seen it in keratinocytes!  Seems the literature has now come full circle. I'm 100% sure I've given a long discussion of LPLK being a pattern not a diagnosis.