|THROUGH THE DERMOSCOPE
|Ahead of print publication
Dermoscopy of black heel
Department of Dermatology and STDs, Dr. RML Hospital and ABVIMS, New Delhi, India
|Date of Submission||27-Feb-2020|
|Date of Decision||12-May-2020|
|Date of Acceptance||20-Jul-2020|
|Date of Web Publication||19-Sep-2020|
Department of Dermatology and STDs, Dr. RML Hospital and ABVIMS, New Delhi - 110 001
Source of Support: None, Conflict of Interest: None
A 75-year-old housewife presented with reddish brown to dark black asymptomatic spots over right heel [Figure 1]. She was a diabetic, well controlled on treatment and had no other co-morbidities. She denied history of trauma, fever or any systemic illness. Dermoscopy was performed using Dinolite AM 4113 ZT-R4 videodermoscope at a magnification of 70×. It revealed a homogenous pattern of red globules separated by dirty white scales traversing the lesion forming a honeycomb pattern [Figure 2]. The globules occupied the “furrows”, while the scales covered the “ridges”. Notably, there was no discernible pigmentary pattern suggestive of a melanocytic lesion. One lesion was pared using No 21 surgical blade with which the black color was partially removed while no bleeding occurred. A diagnosis of talon noir (TN) was made and the patient was counseled of its benign nature.
|Figure 2: Reddish globular structures occupying the furrows with over-running scales on the ridges, forming a honeycomb pattern (using Dinolite AM 4113 ZT-R4 videodermoscope, at 70X magnification)|
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Brownish-black pigmented lesions on the soles arouse suspicion of a multitude of disorders ranging from innocuous ones like warts, lentigines or traumatic tattoo to significant ones such as infective endocarditis, purpura fulminans and melanoma. While infective endocarditis and purpura fulminans would be associated with systemic features and are readily diagnosed in an appropriate clinical setting, acral melanomas (AM) need meticulous assessment to be ruled out. TN (also called black heel, calcaneal petechiae, purpura traumatica pedis or tennis heel) presents with isolated or multiple lesions resulting from capillary haemorrhage within papillary dermal capillaries leading to lakes of blood in the epidermis. The leakage into epidermis possibly occurs via sweat ducts, which provide a pathway of least resistance for the blood to escape. The condition usually occurs in those involved in sports but has been seen to develop without such history as well. AMs have a strikingly similar clinical appearance. They constitute the commonest form of melanoma seen in darker phenotypes and affect older age groups, like our patient. However, AMs typically show a parallel ridge pattern on dermoscopy with irregular melanin pigmentation. The appearance of TN at a high magnification of 70× as described here is useful to bring about a clear differentiation from AM, as overlapping features with AM have been described at lower magnifications.,
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.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
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[Figure 1], [Figure 2]