Case Number : Case 2683 - 19 October 2020 Posted By: Dr. Mona Abdel-Halim

irregular acanthosis with sub corneal vesicle with serum exudates. Dermal perivascular lymphocytes and a few eosinophils

PAS to exclude dermatophytosis

DD: Pityriasis rosea

Agree.  A subcorneal pustule in the groin is most likely to be fungus or Candida. The rather top-heavy histology makes it more likely that this is an exogenous problem than an endogenous condition such as sub-corneal pustular dermatosis or pustular psoriasis.

Scabies?

Fungal infection.

Will do a PAS first to check for Fungus/Candida. Psoriasis in the flexural region can also be quite spongiotic, so will keep this also as a possibility. Need CPC. 

9 hours ago, Meenakshi Batrani said:

Will do a PAS first to check for Fungus/Candida. Psoriasis in the flexural region can also be quite spongiotic, so will keep this also as a possibility. Need CPC. 

I would rule out scabies, but like this comment, because of the tangle of capillary vessels in papillary dermis. 

I find it difficult to be certain about the nature of the subcorneal collection i.e exudate rich in neutrophil/impteginised vs true subcoreneal pustule, infective aetiology needs to be excluded first.

Was interested to know what clue suggests possible scabies? hope Vincenzo will be able to educate us.

12 hours ago, Saman Fatah said:

I find it difficult to be certain about the nature of the subcorneal collection i.e exudate rich in neutrophil/impteginised vs true subcoreneal pustule, infective aetiology needs to be excluded first.

Was interested to know what clue suggests possible scabies? hope Vincenzo will be able to educate us.

Saman, scabies is only on my brain, because of some eosinophil in papillary dermis and some swirl keratin material in stratum corneum. But probably I’m wrong...

Thanks for explaining the reason for that thought, we will wait to hear from Mona about the final diagnosis.

Sorry for the small size of the image! The PAS revealed fungal structures, this was a case of Tinea cruris. The 4th image shows (with the eyes of faith!) a tiny hyphal structure within a compact stratum corneum. Thank you all! I apologize for the late posting of the answer! Stay safe!