Histopathologic examination of a biopsy specimen revealed a cornified layer with increased thickness. Several columns of parakeratosis traversed the full thickness of the cornified layer. Beneath the column of parakeratosis, there was a loss of granular zone, and there were dyskeratotic cells in the superficial epidermis. These changes were consistent with multiple cornoid lamellae. At least 1 cornoid lamella was observed in the ostium of a hair follicle. The vital epidermis showed slight irregular acanthosis. No atypia was detected. Within the dermis, there was a superficial perivascular inflammatory infiltrate of lymphocytes and macrophages. Focally, there was squamatization of the basal zone of the epidermis, with slight pigmentary incontinence. Two biopsy specimens revealed the same features, with no malignant transformation.
CARRIE ANN RC, SENAIT ANN WD, MOLLY AH, VINCENT L. Pruritic Natal Cleft Plaque—Diagnosis. Arch Dermatol. 2010;146(8):911-916. doi:10.1001/archdermatol.2010.171-b