[Leukoencephalopathy with swelling, megalencephalopathy and surprisingly mild course. A case report].

Leukoencephalopathy with swelling and a discrepantly mild clinical course is a recently identified syndrome described by van der Knaap et al. It is characterised by macrocephaly occurring during the first year of life, initially normal or nearly normal development, slowly progressive ataxia and spasticity with initial preservation of intellectual functions. MRI shows diffuse abnormality of signal intensity in the hemisphere white matter with subcortical cyst-like spaces in the fronto-parietal and anterior temporal areas. The case of a 5-year-old boy whose clinical and neuroimaging findings are consistent with this syndrome is reported. The clinical and neuroimaging findings of this case may provide further information about this new syndrome which could possibly be useful also for genetic counselling.