Porokeratosis ptychotropica: a rare case report with unusual presentation


  • Sangheetha K. Department of Dermatology, Dhanalakshmi Srinivasan Medical College and Hospital, Perambalur, Tamil Nadu, India
  • Raja Shareef A. Department of Dermatology, Dhanalakshmi Srinivasan Medical College and Hospital, Perambalur, Tamil Nadu, India
  • Azeem Jaffer N. Department of Dermatology, Dhanalakshmi Srinivasan Medical College and Hospital, Perambalur, Tamil Nadu, India




Gluteal cleft, Multiple coronoid lamella, Porokeratosis ptychotropica


Porokeratosis is a rare disorder of epidermal keratinization characterized clinically by annular plaque with thread like hyperkeratotic border with a central groove that expand centrifugally and this border corresponds to coronoid lamellae histologically which are the columns of parakeratosis that overlie an epidermal invagination with loss of granular layer and dyskeratosis of upper spinous keratinocytes. The disorder was erroneously named porokeratosis because the coronoid lamella was initially described as being present over a sweat pore, which is a fixed structure that cannot expand peripherally. Five primary clinical variants have been described: classic porokeratosis of mibelli, disseminated superficial actinic porokeratosis, linear porokeratosis, punctate porokeratosis and porokeratosis palmaris et plantaris disseminate. Porokeratosis ptychotropica one of the rare variants of porokeratosis described by lucker et al which has been added recently in the classification. It is characterized clinically by symmetrical verrucous papules and plaques resembling psoriasis plaque in the gluteal cleft, buttocks and rarely extends to genitalia and histologically by multiple coronoid lamella. We report a case of 43year old female, presented with 10years duration of pruritic raised skin lesion over the left gluteal region. Dermatological examination revealed single well defined erythematous scaly plaque with central atrophy, hyperpigmentation and peripheral thread like elevated border. Histopathological examination revealed multiple coronoid lamella which is the hallmark for porokeratosis ptychotropica, confirmed the diagnosis. The patient was treated with 5-fluorouracil cream. we report this case due to its rarity and the unusual presentation of single plaque of porokeratosis ptychotropica.


O’Regan GM, Irvine AD. Disorders of epiderm differentiation and keratinization: porokeratosis. In:Fitzpatrick TB, Goldsmith LA, editors. Fitzpatrick’s Dermatol in gen med. 8th ed. New York, NY:McGraw-Hill Medical; 2012:563-568.

Joshi R, Minni K. Genitogluteal porokeratosis: a clinical review. Clinical, Cosm and Investigation Dermatol. 2018;11:219.

Chu AC, Teixeira F. Acquired disorders of epidermal keratinization. In: Griffiths C, Barker J, Bleiker T, Chalmers R, Creamer D. Rook’s Textbook of Dermatol. 9th ed. Chichester, UK: Wiley Blackwell; 2016:18-22.

Tebet AC, Oliveira TG, Oliveira AR, Moriya FS, Oliveira Filho JD, Cucé LC. Porokeratosis ptychotropica. Anais Brasileiros de Dermatol. 2016 Oct;91(5):134-6.

Lucker GP, Happle R, Steijlen PM. An unusual case of porokeratosis involving the natal cleft: porokeratosis ptychotropica?. Brit J Dermatol. 1995 Jan;132(1):150-1.

Joshi R, Jadhav Y. Penoscrotal porokeratosis: A distinct entity. Indian Dermatol Online J. 2015 Sep;6(5):339.

Takiguchi RH, White KP, White Jr CR, Simpson EL. Verrucous porokeratosis of the gluteal cleft (porokeratosis ptychotropica): a rare disorder easily misdiagnosed. J Cutaneous Pathol. 2010 Jul;37(7):802-7.

D'souza P, Dhali TK, Arora S, Gupta H, Khanna U. Porokeratosis ptychotropica: a rare variant of porokeratosis. Dermatol online J. 2014 Jan 1;20(6).

Yu YF, Wu YH. Verrucous porokeratosis (porokeratosis ptychotropica) with dermal amyloid deposits. Dermatologica Sinica. 2013 Sep 1;31(3):145-8.

Hazarika D, Pawar M. Hyperkeratotic porokeratosis ptychotropica with satellite lesions: a rare presentation of an unusual variant of porokeratosis. Acta dermatovenerologica Alpina, Pannonica, et Adriatica. 2017 Dec;26(4):113-4.




How to Cite

K., S., A., R. S., & N., A. J. (2018). Porokeratosis ptychotropica: a rare case report with unusual presentation. International Journal of Research in Medical Sciences, 7(1), 313–316. https://doi.org/10.18203/2320-6012.ijrms20185400



Case Reports