Table 2.

Megalencephalic Leukoencephalopathy with Subcortical Cysts (MLC): Comparison of Phenotypes by Select Features

FeatureClassic MLCImproving MLC
Macrocephaly, typically persistent~95%~55%
Motor delays, initial~30%~15%
Ataxia~80%~20%
Pyramidal dysfunction~20%~5%
Cognitive delays~70%~30% (mild ID)
Autism spectrum disorder~10%~25%
Seizures~65%~10%
Brain MRI abnormalities100%Initially 100%, but typically followed by improvement or normalization

Data based on Hamilton et al [2018]

ID = intellectual disability; MLC = megalencephalic leukoencephalopathy with subcortical cysts

From: Megalencephalic Leukoencephalopathy with Subcortical Cysts

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