Porokeratosis: A diagnosis made easy by the dermoscope!

Samia Mrabat, Hanane Baybay, Sabrina Oujdi, Zakia Douhi, Sara Elloudi, Fatima Zahra Mernissi

Department of Dermatology, University Hospital Hassan II, Fes, Morocco

Corresponding author: Samia Mrabat, MD

Submission: Submission: 12.08.2020; Acceptance: 31.10.2020

DOI: 10.7241/ourd.2020e.141

Cite this article: Mrabat S, Baybay H, Oujdi S, Douhi Z, Elloudi S, Mernissi FZ. Porokeratosis: A diagnosis made easy by the dermoscope!. Our Dermatol Online. 2020;11(e):e141.1.

Citation tools: 


Related Content

Copyright information
© Our Dermatology Online 2020. No commercial re-use. See rights and permissions. Published by Our Dermatology Online.

A 56 year-old woman with no medical history presented with an asymptomatic lesion on her right thigh that had been evolving for 20 years. Clinical examination showed an oval shape plaque ; with a slightly erythematous atrophic center surrounded by a hyperkeratotic border (Fig. 1). On dermoscopy, we found a diffuse brown central area of atrophy bounded by irregular double-marginated “white track” border (Fig. 2) consistent with the diagnosis of porokeratosis of Mibelli.

Figure 1: An oval shape plaque; with a slightly erytematous atrophic center surrounded by hyperkeratotic border on the right thigh.
Figure 2: A diffuse brown central area of atrophy bounded by irregular double-marginated white track (arrow).

Porokeratoses (PK) are a group of disorders of keratinization characterized by annular lesions surrounded by a characteristic keratotic border which corresponds to a typical histopathologic feature, namely, the coronoid lamella. Though no pathognomonic, the coronoid lamella is the most distinctive feature of the various types of porokeratosis [1]. Dermoscopy is very useful because it reveals specific diagnostic criteria : A peripheral white rim, corresponding to the coronoid lamella, which is the dermoscopic hallmark of porokeratosis [2]. This criteria allows us to confirm the diagnosis without resorting to histology.


The examination of the patient was conducted according to the principles of the Declaration of Helsinki.


1. Delfi no M, Argenziano G, Nino M. Dermoscopy for the diagnosis of porokeratosis. JEADV. 2004;18:194–5.

2. Moscarella E, Longo C, Zalaudek I, Argenziano 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.


Source of Support: Nil,

Conflict of Interest: None declared.

Request permissions
If you wish to reuse any or all of this article please use the e-mail (brzezoo77@yahoo.com) to contact with publisher.

Related Content:

Related Articles Search Authors in


Comments are closed.