Siblings with megalencephalic leukoencephalopathy with subcortical cysts van der Knaap disease.

Cerebral leukoencephalopathy and megalencephaly with subcortical cysts (also known as van der Knaap disease) is an autosomal recessive condition. The disease was initially described in India and Netherlands independently and seems to have highest incidence in Indian Agrawal community and Turkish population. The objective of this study is to document the case of two siblings with this condition, from a non-Agrawal Indian community and briefly describe the imaging features of this condition. Two siblings, born out of a third-degree consanguineous marriage, with simple focal seizures were subjected to MRI with diffusion-weighted imaging and spectrometry. The findings were compared to diseases with similar clinical presentation. Subcortical cysts initially involving anterior temporal lobes and subsequently frontal and parietal lobes, sparing of central white mater, small N acetyl aspartate peak and diffusion facilitation were the imaging findings. The imaging findings were consistent with the diagnosis of the rare genetic disorder- Cerebral leukoencephalopathy and megalencephaly with subcortical cysts.