Hypomelanosis of Ito: a syndrome requiring a multisystem approach.

Hypomelanosis of Ito can be defined as a syndrome providing a cutaneous epiphenomenon with a peculiar pattern of distribution, usually associated with disorders of the nervous system, skeleton and eyes. Four further patients are reported and the literature reviewed. The diagnostic criteria and the differences with other pigmentary diseases distributed along Blaschko's lines are highlighted. The main histopathological features are reported and the high frequency of the associated abnormalities are emphasized. The chromosomal findings and main genetic hypotheses are discussed. The suggested follow-up aims not only at the knowledge of the natural history of this condition, but also at its better delineation.