Increased intracranial pressure in Alexander disease: a rare presentation of white-matter disease.

A patient with biopsy-proven Alexander disease presented with progressive head enlargement and clinical evidence of increased intracranial pressure. Lumbar puncture under sedation confirmed increased intracranial pressure with otherwise normal cerebrospinal fluid values. The association of megalencephaly, increased intracranial pressure and neuroimaging evidence of leukoencephalopathy should alert pediatric neurologists to the possibility of Alexander disease.