Halo naevi with associated vitiligo-like depigmentations: pathogenetic hypothesis.

BACKGROUND

In analogy with melanoma-associated leucoderma, halo naevi may trigger in some patients the development of additional depigmentations which are in distribution, extent and prognosis not in accordance with classic vitiligo.

OBJECTIVE

The aim of this study was to support the hypothesis that in a subset of halo naevi patients vitiligo-like lesions develop directly linked to the halo phenomenon.

METHODS

Forty-one patients with halo naevi were examined for the development of depigmentations not corresponding to typical vitiligo lesions.

RESULTS

We identified a subset of five halo naevi patients with additional subtle depigmentations. After the occurrence of multiple halo naevi, they developed leucoderma that showed a different disease pattern than vitiligo (variable asymmetric distribution, limited extent and lack of progression). Moreover, the characteristics of these halo naevi patients with associated leucoderma were different from classic vitiligo patients (high number of halo naevi, absence of family history for vitiligo and absence of autoimmune diseases) and the timing of occurrence of the leucoderma suggested a direct relation with the halo phenomenon.

CONCLUSIONS

In this article, we describe in a limited subset of patients with multiple halo naevi discrete depigmentations at distance from halo naevi which may result from a temporary autoimmune process directly linked to the halo phenomenon. This finding illustrates the collateral damage resulting from skin immunosurveillance and may have clinical consequences as the evolution pattern in this subset of patients is less progressive compared with vitiligo. We present clinical data that support this hypothesis and suggest to call it 'halo naevi-associated leucoderma'.