A 35 years old female presented a 2 years history of rash, which started after the exposure of a hot tub on the gluteal cleft and then spread to the areas under both breasts, in the belly bottom, and armpits. The belly bottom lesions were cleared meantime. History of one time episode of dandruff is noted. All of prior treatments (Niftin, Vusion, OTC barrier creams, prescribed cortisone etc.) were unsuccessful. She was using cottonelle wipes for the bottom. No family history of psoriasis was present. Clinical impressions included an inverse psoriasis, lichen simplex chronicus with postinflammatory hypo/hyperpigmentation, LS&A, contact dermatitis, vitiligo, and candida/intertrigo.
Pathology Findings: A skin punch biopsy showed a spongiform dermatitis with mild parakeratosis. At high magnification, careful examination identified intracorneal filaments and rods of bacterial organisms. Superficial dermis shows moderate perivascular chronic inflammatory cell infiltrate with occasional eosinophils. On the special stains including PAS, Giemsa, and Gram stains, most of intracorneal organisms were not present since the corneal layer disappeared and H&E findings were the most diagnostic for this case.