CENTRAL-NERVOUS-SYSTEM LESIONS IN HYPOMELANOSIS OF ITO - AN MRI AND PATHOLOGICAL-STUDY

A severe form of hypomelanosis of Ito is reported, which presented as fetal macrocephaly and neonatal epileptic encephalopathy. Lymphocyte k aryotypes were normal. MRI showed an absence of delineation between co rtical grey matter and white matter. The prominent neuropathological f inding was an abnormal cortical morphogenesis, with the co-existence o f cells migrating normally and cells exhibiting arret en route or even the complete absence of migration. Intense astrocytic reaction with m oderate dystrophic features was present. Juxtaposition of two migratio n behaviours in the neural cells paralleled the cutaneous findings and reinforced the hypothesis of a genetic chimerism.