Axillary Granular Parakeratosis

David A. Mehregan, MD, Paul Vandersteen, MD, Lynn Sikorski, DO, and Darius R. Mehregan, MD, Monroe, Michigan
We report two cases of axillary granular parakeratosis which is a unique eruption involving the axilla that has distinctive histopathologic features. Both of our patients had slightly pruritic, hyperpigmented patches in the axilla. The biopsy specimens revealed severe compact parakeratosis with maintenance of the stratum granulosum and retention of keratohyalin granules throughout the stratum corneum which was markedly thickened and measured between 90 to 185 um. The exact etiology is not known, but this condition is believed to represent a contact reaction to an antiperspirant or deodorant.

JAAD 1995; 33; 373-5