Indian Journal of Dermatopathology and Diagnostic Dermatology

LETTER TO EDITOR
Year
: 2020  |  Volume : 7  |  Issue : 2  |  Page : 100--101

Dermoscopy of disseminated superficial actinic porokeratosis in skin of color


Yasmeen Jabeen Bhat1, Nahida Nabi1, Rohi Wani2,  
1 Department of Dermatology, Venereology and Leprosy, GMC Srinagar, University of Kashmir, Srinagar, Jammu and Kashmir, India
2 Department of Pathology, GMC Srinagar, University of Kashmir, Srinagar, Jammu and Kashmir, India

Correspondence Address:
Yasmeen Jabeen Bhat
Department of Dermatology, Venereology and Leprosy, GMC Srinagar, University of Kashmir, Srinagar, Jammu and Kashmir
India




How to cite this article:
Bhat YJ, Nabi N, Wani R. Dermoscopy of disseminated superficial actinic porokeratosis in skin of color.Indian J Dermatopathol Diagn Dermatol 2020;7:100-101


How to cite this URL:
Bhat YJ, Nabi N, Wani R. Dermoscopy of disseminated superficial actinic porokeratosis in skin of color. Indian J Dermatopathol Diagn Dermatol [serial online] 2020 [cited 2021 Jul 23 ];7:100-101
Available from: https://www.ijdpdd.com/text.asp?2020/7/2/100/304337


Full Text



Sir,

A 27-years-old male presented with complaints of raised pigmented lesions over the face for the past 5 months. It started as small asymptomatic skin-colored lesions which gradually increased peripherally with raised margins and central clearing. He complained of burning sensation, itching, and redness over the lesions. There was no history of oral or topical application of drugs and cosmetics, excessive sun exposure, or insect bite. On examination, well-defined, small hyperpigmented plaques 2 cm × 3 cm in size, with central atrophy and surrounding raised thread-like border, were seen bilaterally over the face [Figure 1].{Figure 1}

Dermoscopy of the lesions showed peripheral brownish globules arranged in annular pattern superimposing the less well-defined inner rim of whitish areas. Occasional red dots and light brown blotches in the center were seen [Figure 2]a and [Figure 2]b. A 5-mm punch biopsy specimen of peripheral hyperkeratotic ridge was obtained. The histopathological examination showed hyperkeratosis and mounds of parakeratosis dipping in the epidermis with increased basal cell pigmentation. Dermis showed pigment incontinence, dilated capillaries, and inflammatory cell infiltrate with lymphohistiocytic cells. The cornoid lamella is the parakeratotic column in which the horny cells appear homogeneous and have a deeply basophilic pyknotic nucleus. The epidermal cells at the base of the cornoid lamella have pyknotic nuclei with perinuclear edema and absent granular layer [Figure 3]a and [Figure 3]b.{Figure 2}{Figure 3}

On the basis of clinical, dermoscopic, and histopathological evidence, the diagnosis of disseminated superficial actinic porokeratosis (DSAP) was made, and the patient was put on oral isotretinoin and topical sunscreen. Porokeratosis is an autosomal dominant disorder of abnormal epidermal keratinization characterized by overexpression of p53 in epidermal cells. Classically, five clinical variants are recognized: classic porokeratosis of Mibelli, disseminated superficial porokeratosis, DSAP, porokeratosis palmaris et plantaris disseminata, and linear porokeratosis.[1]

Superficial varieties of porokeratosis may be difficult to diagnose because of imperceptible or incomplete ridges at the edge of the lesions. Moreover, biopsy sections may sometimes miss the typical cornoid lamella, making the diagnosis more difficult. In such instances, characteristic dermoscopic features help in the diagnosis of porokeratosis. Dermoscopy helps in distinguishing porokeratosis from psoriasis and annular lichen planus and also aids in early detection of its transformation into basal cell carcinoma and squamous cell carcinoma.[2]

Dermoscopy of DSAP usually demonstrates annular structures with hyperpigmented border, with central demarcating flat pink–white scar-like area, corresponding to the parakeratotic column.[3] Furthermore, multiple red dotted and linear irregular vessels correspond to dilated capillaries below the atrophic epidermis. Brownish globules on the inner side of the white track correspond to melanin in the dermis. Brownish or whitish center showing linear or circular whitish or hyperpigmented tracks corresponds to acanthotic epidermis.[4],[5] Contrary to white skin, in our patient, with skin Type IV, the central vascular structures were inapparent and got overshadowed by the pigmented dots and blotches. More importantly, the annular rim of the white track is inconspicuous and shows dark brown to almost black dots and globules that form an almost incomplete outer track due to the increased basal cell layer pigmentation as well as pigmentary incontinence in the dermis as has been reported in Asians.[6]

Thus, dermoscopy is a noninvasive technique that can help to diagnose and distinguish porokeratosis from other close clinical differentials, thus obviating the need for biopsy, but the features varying slightly in different skin types.

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

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Peterson JW. Disorders of epidermal maturation and keratinization. In: Weedon D, editor. Skin Pathology. 4th ed. China: Elsevier; 2015. p1097
2.Lee HR, Han TY, Son SJ, Lee JH. Squamous cell carcinoma developing within lesions of disseminated superficial actinic porokeratosis. Ann Dermatol 2011;23:536-8.
3Nicola A, Magliano J. Dermoscopy of disseminated superficial actinic porokeratosis. Actas Dermosifiliogr 2017;108:e33-7.
4Delfino M, Argenziano G, Nino M. Dermoscopy for the diagnosis of porokeratosis. J Eur Acad Dermatol Venereol 2004;18:194-5.
5Moscarella E, Longo C, Zalaudek I, Agenziano G, Piana S, Lallas A. Dermoscopy and confocal microscopy clues in the diagnosis of psoriasis and porokeratosis. J Am Acad Dermatol 2013;69:e231-3.
6Osio N, Kawada A. Dermoscopic features in disseminated superficial actinic porokeratosis. Eur J Dermatol 2011;21:439-40.