EC Neurology

Megalencephalic leukoencephalopathy with subcortical cysts, or Van der Knaap disease, is a rare genetic disorder characterized by the mutation of the MLC1 gene. It is most commonly observed in ethnicities with a high rate of consanguinity. Symptoms typically appear around 6 months of age and include macrocephaly, ataxia, spasticity, and psychomotor deterioration. MRI scans show swollen cerebral white matter and subcortical cysts in the anterior temporal and fronto-parietal regions. MRI spectroscopy shows decreased levels of normal neuronal white matter metabolites and a decreased NAA/Cr ratio. Similar symptoms of leukoencephalopathy and early onset macrocephaly can also be found in other conditions such as Canavan disease, Alexander disease, and infantile-onset GM2 and GM1 gangliosidosis.

 Keywords: Megalencephalic Leukoencephalopathy; Subcortical Cysts; Van der Knaap; MRI Spectroscopy; Macrocephaly

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