Microscopic examination of the biopsy specimen revealed a markedly thickened stratum corneum, which exhibited parakeratosis and retention of keratohyalin granules. Within the dermis, there was a mild perivascular infiltrate consisting of lymphocytes, histiocytes, and eosinophils. A periodic acid–Schiff stain was negative for fungi.
The axillary rash subsequently cleared without treatment but recurred 3 months later, after the patient underwent clarithromycin therapy for a bout of severe bronchitis. The patient refused treatment with topical or oral retinoids. The eruption cleared after spontaneous desquamation. 1% Hydrocortisone cream was used as needed for pruritus. The patient declined patch testing.
Crusted Plaques in the Axillae. Arch Dermatol. 2001;137(9):1241-1246. doi: