|Year : 2017 | Volume
| Issue : 2 | Page : 76-77
Porokeratosis of mibelli of upper lip extending into oral mucosa
Ragunatha Shivanna1, Meenakshi Kapoor2, Gangaiah Narendra3
1 Department of Dermatology, Venereology and Leprosy, ESIC Medical College and PGIMSR, Bengaluru, Karnataka, India
2 Skin Laser Centre, Avtar Enclave, Paschim Vihar, New Delhi, India
3 Department of Dermatology, Venereology and Leprosy, Sri Siddhartha Medical College, Tumkur, Karnataka, India
|Date of Web Publication||28-Jul-2017|
B-5/35, Sector-7, Rohini, New Delhi - 110 085
Source of Support: None, Conflict of Interest: None
Porokeratosis is a rare specific disorder of keratinization with distinct clinical and histopathological features with rare malignant degeneration. Clinically, it is characterized by papular lesions or annular plaques with central atrophy and peripheral keratotic ridge and histologically with the presence of cornoid lamellae. It mainly presents on the extremities, trunk, face, and very rarely on genitals and mucous membrane. Very few cases of porokeratosis with oral mucosal involvement have been reported in the past. A 50-year-old female presented with a well-demarcated, irregular plaque with atrophic center and peripheral keratotic margin with a thin furrow involving the left side of the upper lip, angle of mouth, and adjacent labial mucosa. The patient had a history of application of topical steroid preparations intermittently over a period of 2 years. The histopathological features showed characteristic cornoid lamellae. The involvement of mucosa is uncommon, and local immunosuppression caused by topical steroids may act as a predisposing factor.
Keywords: Cornoid lamella, parakeratosis, porokeratosis, porokeratosis of Mibelli
|How to cite this article:|
Shivanna R, Kapoor M, Narendra G. Porokeratosis of mibelli of upper lip extending into oral mucosa. Clin Dermatol Rev 2017;1:76-7
| Introduction|| |
Porokeratosis is a specific disorder of keratinization characterized histologically by the presence of cornoid lamella. Various types of porokeratosis have been identified. Porokeratosis of Mibelli is a rare type with onset in childhood. Large lesions of long duration may undergo malignant degeneration.
| Case Report|| |
A 50-year-old female presented to the dermatology outpatient department with an asymptomatic skin lesion on the upper lip of 2 years' duration. The lesion started insidiously as a skin-colored papule near the angle of mouth. The papule gradually increased in size extending into the angle of mouth and adjacent labial mucosa and also on the upper lip. Except for occasional crusting and scaling, there was no history of any discharge from the lesion. The lesion continued to progress in spite of application of several topical steroid preparations, though intermittently, during 2-year period. On examination, a well-demarcated, irregular plaque with atrophic center and peripheral keratotic margin with a thin furrow [Figure 1] involving the left side of the upper lip, angle of mouth, and adjacent labial mucosa was noted. Examination of the oral mucosa revealed angular cheilitis, poor oral hygiene, and periodontitis with loosening of teeth. Histopathology of skin biopsy specimen showed cornoid lamella with underlying agranulosis [Figure 2]. Based on clinical and histopathological features, a diagnosis of plaque type of porokeratosis of Mibelli was made.
|Figure 1: A well-demarcated, irregular plaque with atrophic center and peripheral keratotic margin with a thin furrow|
Click here to view
|Figure 2: Column of parakeratotic cells extending through stratum corneum with underlying agranulosis (H and E, ×40)|
Click here to view
| Discussion|| |
Porokeratosis of Mibelli is characterized by annular hypertrophic plaques with central area of atrophy and raised hyperkeratotic borders. The presence of gutter-like longitudinal furrow in the keratotic border is the clinical hallmark of porokeratosis. The lesions predominantly involve extremities including palms and soles. Involvement of face extending into the upper lip and adjacent labial mucosa is extremely rare as in the present case. Solitary plaque of labial commissure with contagious mucosal involvement  similar to our case and isolated involvement of mucosa of lower lip  have been reported. Clinically, the solitary lesion of porokeratosis has to be differentiated from atrophic annular lichen planus, elastosis perforans, Bowen's disease, squamous cell carcinoma, discoid lupus erythematosus, and sometimes, lupus vulgaris.
The disease usually affects children aged between 5 and 10 years with an autosomal dominant inheritance, though the lesions can occur sporadically. However, the disease can occur in adults indicating a possibility of other underlying etiological factors. Immunosuppression and chronic actinic exposure have been recognized as predisposing factors in the occurrence of porokeratosis, especially disseminated superficial actinic porokeratosis. Porokeratosis of Mibelli has been reported following bone marrow transplantation  and immunosuppression therapy  including topical steroids  as in the present case. In such scenarios, the disease can present with the appearance of lesions de novo or as exacerbation of preexisting disease.
The characteristic hyperkeratotic border is histologically represented by stakes of parakeratotic cells arranged in a column termed as cornoid lamella. Although considered as a pathognomonic feature, it has also been reported in seborrheic keratosis, verruca vulgaris, actinic keratosis, squamous cell carcinoma in situ, basal cell carcinoma, and milium. The granular layer underlying parakeratotic column is either diminished or absent.
| Conclusion|| |
Distinctive clinical and histological features help in the diagnosis of porokeratosis of Mibelli. The involvement of mucosa is uncommon, and local immunosuppression caused by topical steroids may act as a predisposing factor in adults.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Ataseven A, Öztürk P, Dilek N, Küçükosmanoglu I. Localized actinic nasal porokeratosis: A case report. Acta Dermatovenerol Alp Pannonica Adriat 2012;21:79-80.
Du-Thanh A, Frouin E, Vignon-Pennamen MD, Debu A, Guillot B, Dereure O. Solitary plaque of the labial commissure with contiguous mucosal involvement: A distinct subset of porokeratosis? Eur J Dermatol 2013;23:722-3.
Darling MJ, Lambiase MC, Viernes J. Porokeratosis: A solitary oral lesion. J Drugs Dermatol 2005;4:89-91.
Wilkinson SM, Cartwright PH, English JS. Porokeratosis of Mibelli and immunosuppression. Clin Exp Dermatol 1991;16:61-2.
Yazkan F, Turk BG, Dereli T, Kazandi AC. Porokeratosis of Mibelli induced by topical corticosteroid. J Cutan Pathol 2006;33:516-8.
Alexis AF, Busam K, Myskowski PL. Porokeratosis of Mibelli following bone marrow transplantation. Int J Dermatol 2006;45:361-5.
[Figure 1], [Figure 2]