Generalized dermal melanocytosis.

A female infant was born with generalized blue-gray discoloration of the skin. Light microscopy demonstrated the diffuse distribution of dihydroxyphenylalanine-positive, dermal melanocytes. Electron microscopy confirmed the identification of the pigment-bearing cells as melanocytes and demonstrated individual melanocytes to be invested with a filamentous extracellular sheath. To our knowledge, comparable, generalized, dermal melanocytosis has not previously been reported in a newborn.