Case Number : Case 1526 - 29 April Posted By: Guest

Lichen nitidus

Agree

Claw-like downgrowths of the rete ridges are present at the margins of the infiltrate but sincerly i thought of lichen striatus However there isnt any perieccrine infiltrate. So i agree with Raul and Nitin. LICHEN NITIDUS.

Yes! There are giant cells also. I didn't see this with smartPhone..

Yes, there is a focal lichenoid infiltrate, but I can see some infiltrate extending to intermediate and deep vessels and adnexial ducts as well. Without clinical information I prefer a diagnosis of Lichen striatus.

First thought was lichen nitidus too. But Igor has a valid point about the infiltrate extending deeper around adnexal structures in very 'lichen striatus' type patten. Difficult...but overall, I think the superficial dermal/epidermal pattern is so distinctive for lichen nitidus, that this would take precedence, hence favour lichen nitidus!

Found an interesting reference of a periappendageal lichen nitidus:

http://www.ncbi.nlm.nih.gov/pubmed/12150134?dopt=Abstract

Nice discussion and I am glad I did not give the history which was as follows:

Widespread rash, tiny 1mm papules, slightly vioilaceous, itchy. DDx: Lichen nitidus, LP, eczema.

My report: Papular, focally granulomatous, papillary dermal inflammatory reaction in keeping with lichen nitidus.

I remember Phillip McKee saying something to the effect that if you have a cat with one leg missing it is still a cat.  I would add if a cat is wearing a hat it is still a cat!  Of course clinical correlation is essential for most inflammatory cases but this does look fairly typical of lichen nitidus as a most likely first diagnosis but fully agree to consider lichen striatus in a different clinical context.