Case Number : Case 2680 - 14 October 2020 Posted By: Dr. Hafeez Diwan

Mastocytosis-TMEP?

There is fibrosis in papillary dermis. 

I would exclude fungus with a PAS stain, but I think the most likely diagnosis is erythema annulare centrifugum.

Probable pityriasiform spongiosis pattern with a few conditions exhibiting such microscopic appearance as listed by Weedon including EAC as suggested by Richard.

I am uncertain about the exact nature of infiltrate within dermis, some looks like mast cells and others possibly lymphoid with variable nuclear contours. Clinical correlation is essential and if above diagnoses were unlikely, then an early stage CTCL may be down the bottom of list in the differential diagnoses.

i will call it spongiotic dermatitis , get a PAs stain done to rule out dermatophytosis

figurate erythema versus pityriasis rosea.I favor the latter.

On 17/10/2020 at 11:19, dermpath1 said:

figurate erythema versus pityriasis rosea.I favor the latter.

Quote

Agree.

I went with EAC. Fungal stain was negative.  Pityriasis rosea was in the differential. Clinically, it was considered to be EAC.