Talon noir pathology

Author: Dr Ben Tallon, Dermatologist/Dermatopathologist, Tauranga, New Zealand, 2011.


Talon noir is also called ‘black heel’ or calcaneal petechiae, talon noir is considered to be induced by trauma.

Histology of talon noir

Low power of the histology of talon noir demonstrates acral skin, with notable hyperkeratosis and epidermal acanthosis (Figure 1). The changes are seen within the epidermis. There is inspisated hemorrhage focally and in pools within the stratum corneum (Figure 2, 3 and 4). Telangiectatic vessels and extravasation of erythrocytes may be noted in the papillary dermis (Figure 3).

Talon noir pathology

Differential diagnosis of talon noir

Verruca vulgaris: Focal hemorrhage is typically seen overlying areas of papillary projection (cap-like hemorrhage), and the additional epidermal changes of a wart make this distinction straight forward in most cases.

The main clinical differential diagnosis is of a melanocytic proliferation (melanoma) or other cutaneous malignancy. Careful inspection is essential so as not to overlook a concurrent melanocytic tumour.

 

Related Information

References:

  • Skin Pathology (3rd edition, 2002). Weedon D
  • Pathology of the Skin (3rd edition, 2005). McKee PH, J. Calonje JE, Granter SR

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