Case Number : Case 4156 - 26 December 2022 Posted By: Dr. Mona Abdel-Halim

Subcorneal and intraepidermal pustules, and I think there are eosinophils in image 5 ~ probably AGEP. In this clinical setting, culprit drug could be hydroxychloroquine 
DDx includes pustular psoriasis, and others. 
PAS to rule out fungus (less likely).

PS. Maybe there are some fungal elements in image 3?

Fungal infection..

Favouring AGEP (subcorneal pustules, mixed inflammatory infiltrate in the superficial dermis including eosinophils and possible papillary dermal oedema). However also fungal hyphae seen in 3rd picture...AGEP with superimposed fungal infection?

Is the patient immunocompromised? Disseminated dermatophytosis is a possibility in relevant clinical situation. Fungal id is another differential.

More photos should be provided soon

Tinea and AGEP are in differential. But I will also add IgA pemphigus which can have subcorneal / intraepidermal pustules while acantholysis may be inconspicuous. PAS and DIF will help. 

I think the contributors almost listed various causes of subcorneal/high intraepidermal pustulation other than subcorneal pustular dermatosis of Sneddon and Wilkinson!
Knowledge of whether the pustule is sterile or not is crucial through swab results of an intact pustule, stains and tissue cultures especially in those immunocompromised. Then drug exposure and DIF results.

it will be interesting to see if the pustular dermatosis has a predilection for flexures in this lady with SLE, then Amicrobial Pustulosis of the Folds (APF) requires consideration after exclusion of more common causes of such pattern of pustulosis.

On 02/01/2023 at 16:22, Eman El-Nabarawy said:

Fungal infection..

+1. 

Disseminated dermatophyte infection (Tinea incognito)