Case Number : Case 2460 - 6 December 2019 Posted By: Dr. Richard Carr

dermal perivascular plasma cells

can I have serology done. would like to r/o SYphilis

then other causes for plasma cell infiltrate

A difficult granuloma annullare-like interstitial dermatitis, plasma cell rich. ?Erythema migrans

?Inflammatory morphea 

Favor erythema migrans with interstitial granulomatous infiltrate.

Erythema migrans: a reassessment of diagnostic criteria for early cutaneous manifestations of borreliosis with particular emphasis on clonality investigations.

https://www.ncbi.nlm.nih.gov/m/pubmed/17535225/

Hemosiderin deposits are there too! HHV-8??

can we have any lab results

Secondary syphilis with an interstitial granuloma annulare-like histopathologic pattern.

Necrobiosis lipoidica. 

Clinical picture of pigmented patch, lymphocytic vasculitis, hemosiderin, few extravasated RBCs. ? PPD? Lichen aureus. Plasma cells are reported. 

The pathology in lichen aureus is mainly in the papillary dermis. Here, the changes are in deeper dermis. 

7 hours ago, Anil Patki said:

The pathology in lichen aureus is mainly in the papillary dermis. Here, the changes are in deeper dermis. 

Agree with u Sir. Thought of atypical presentation. As NL is a very good idea but I can't explain the hemosiderin in view of it. Also the clinical is not that typical of NL for my eyes at least. Thank u.

can we have any lab results

Secondary syphilis with an interstitial granuloma annulare-like histopathologic pattern.

mid dermal perivascular plasma cells. Lichen aureus is more more lichenoid with hemosiderin pigments, lymphocytes and histiocytes. 

could it be something like Lymphoplasmacytic plaque in children happening in this age group

serology any data sir

Isolated benign primary cutaneous plasmacytosis and erythema migrans are my differentials.

The pigmented lesion looks worrisome clinically. Does the patient get any immunotherapy or anti BRAF therapy for malignant melanoma which might explain the interstitial granulomatous dermatitis?

On 14/12/2019 at 02:16, anh said:

The pigmented lesion looks worrisome clinically. Does the patient get any immunotherapy or anti BRAF therapy for malignant melanoma which might explain the interstitial granulomatous dermatitis?

...other spot: Desmoplastic Melanoma.

31 minutes ago, vincenzo said:

...other spot: Desmoplastic Melanoma.

It was one of my thoughts also especially with this worrisome clinical but why so many plasma cells?! Never seen an interstitial granulomatous dermatitis in setting of melanoma yet!

This is spindle cell melanoma. I've not seen a case with so many plasma cells. I guess we can all add it to our differential of interstitial granuloma annulare-like pattern with plasma cells!!! I'll arrange to post the IHC so you can enjoy it. A great learning case. Phillip Mckee used to say at the beginning of every sign out say to yourself "desmoplastic melanoma". I looked at this case blind twice and each time I forgot this aphorism!  

Yikes!

Wao, clinically definitely it is melanoma but could not relate with histology! Thought Dr Carr is tricking us and hiding something.... great case! Love it :-)