An unusual case of generalized hyperkeratotic and verrucous porokeratosis

Porokeratoma: A distinct variant of porokeratosis

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] Particularly rare clinical variants have been described in the literature, where patients present with hyperkeratotic, verrucous papules, plaques, or nodules in a variety of distributions. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] These lesions have acquired several names: hyperkeratotic PK, genitogluteal PK, F I G U R E 3 Histopathology of giant porokeratoma. (A,B) Parakeratosis and dyskeratotic cells within multiple infundibula (H&E, original magnification Â200) porokeratoma (porokeratotic acanthoma), and PK ptychotropica.…”

“…7,18 Unfortunately, the verrucous variant is often unresponsive to treatment. [1][2][3][4][5][6][7][8][9][10][11][12][13] Some patients received complete resolution without recurrence following oral actitretin or cryotherapy. 3,4 Topical 5-fluorouracil, imiquimod, steroids, and keratolytics have been used with varying success rates.…”

“…1,8,14 The histopathologic finding of vertically stacked parakeratotic corneocytes, known as the cornoid lamella, is the characteristic feature that unifies the various subtypes. [1][2][3][4][5][6][7][8][9][10][11][12][13] Particularly rare clinical variants have been described in the literature, where patients present with hyperkeratotic, verrucous papules, plaques, or nodules in a variety of distributions. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] These lesions have acquired several names: hyperkeratotic PK, genitogluteal PK, F I G U R E 3 Histopathology of giant porokeratoma.…”

“…2 Most cases in the literature of PK ptychotropica describe a similar morphology and progression of lesions: a pruritic papule on the buttock that slowly progresses to reddish-brown, hyperkeratotic, verrucous plaques of the natal cleft with coalescing satellite lesions that may give a butterfly appearance. [2][3][4][5][6][7][8][9][10][11][12][13] Multiple cornoid lamellae are found throughout the lesion 7,11 However, not all verrucous PKs are isolated to the genitals or buttocks. 14 Reports have included patients with several hypertrophic, verrucous plaques on the extremities alongside separate papules consistent with disseminated superficial actinic PKs.…”

“…While the etiology of PK remains unclear, contributing factors are thought to include immunosuppression, trauma from friction or excoriation, and ultraviolet exposure. [2][3][4]10 An autosomal dominant inheritance pattern for disseminated superficial actinic PK has been identified, but the role of genetics and immunosuppression in the verrucous variants is not clearly understood. 12,19 A case series did identify two brothers and a maternal aunt with verrucous PK, suggesting a similar autosomal dominant inheritance pattern.…”