Congenital nevi with hypomelanosis and fine scales.

BACKGROUND

Nevus is a hamartoma or malformation of one or more skin components, resulting in aberrant differentiation of the cell lineage(s) mostly during developmental stages. Although multiple lineages may be involved in a nevus, the combination of melanocyte and keratinocyte abnormalities has been rarely discussed.

OBJECTIVES

To present two cases of congenital nevi with hypomelanosis and superficial fine scales.

MATERIALS &

METHODS

Skin specimens of the patients were analysed by immunohistochemistry and electron microscopy.

RESULTS

Morphological and immunohistochemical studies indicated aberrant epidermal differentiation in the lesional skin specimens. Electron microscopy showed defective melanosome maturation in the melanocytes of the nevi samples.

CONCLUSION

These results demonstrate that both epidermal and melanocytic lineages can concomitantly contribute to the formation of a nevus lesion.