#dermpath#pathology#dermatology
Recent case I had of cutaneous involvement by known granulomatosis with polyangiitis. These were photos I shared with the clinician who was concerned for infection.
1) Another land mine of a case. TRUST YOUR EYES AND TRAINING. 70 y.o 👩 upper arm. “NUB vs BCC” #dermpath
Looks like a BLK, right? What is a big clue that it’s NOT!
2) Where is the disruption? It’s not at the DEJ like one would see in an interface process. It’s INTRAEPIDERMAL (unzippering). Remember melanocytes lack desmosomes=no adherence
Also, see how jumbled and grey the epidermis is? Another clue.
3) IHC to confirm (🧦10 and PRAME). I let out an audible gasp when I got saw them, but was also very relieved that I didn’t go down the tubes with this one (I had great training from @MightyDermPath)! Got the PRAME after the 🧦 for re-excision feasibility purposes.
6yo with recent ptosis
Pic B: Squamous papilloma with marked inflammation??
Pic C: High power shows small round atypical cells.
Final diagnosis: Botryoid type embryonal rhabdomyosarcoma
Dr. Stagner and Zembowicz #ophtalmicpath#dermpath#PathX#PathTwitter#pathologists
40yo. Vague GI symptoms and subsequent rash of edematous and erythematous plaques, starting intertriginous, spreading to trunk and extremities. First pruritus, then tender. No response to low dose steroids. Completely cleared after higher dose. Thx @mccalmo for lighting the way.
Answer: This is a porokeratoma! At low power you see diffuse wave-like, columnar cornoid lamella with an abrupt transition from normal. Read more about this entity here: onlinelibrary.wiley.com/doi/…
#COTW with PGY1 @meredithkherman featuring a variant in #dermpath. Shave biopsy of groin lesion. What histologic features do you see? What is your differential diagnosis?
I believe we can. Now, let’s look on high-power. What’s going on? How would you describe the papillary dermis? What’s your ddx and which stain(s) should you get?
So to recap: this is (macular) localized cutaneous amyloidosis. Presents as (usually) pruritic hyperpigmented macules/patches, usually on upper body/extremities. Amyloid is keratin-derived. Amorphous eosinophilic deposits (some)🐷 incontinence.
This is a CK5/6 (of course I also got a PAS which was neg for fungi). Look @ how that material lights up! This is keratin-derived amyloid. Since there’s minimal epidermal change, I decided “c/w macular amyloid” (vs lichen).