December 7, 2015: Adult-onset Alexander disease
December 7, 2015
Adult-onset Alexander disease
Alexander disease (AD) is an autosomal dominant leukodystrophy caused by mutation in the gene for GFAP on chromosome 17. It is classically seen in infants and children, characterized by macrocephaly, seizures, spasticity, and psychomotor retardation, leading to death within 10 years. MRI shows frontal-predominant white matter signal change and periventricular enhancement.1 Adult-onset AD (>12 years) presents commonly in the 4th to 5th decade with a less severe course, characterized by progressive bulbar dysfunction, spastic paraparesis, ataxia, palatal myoclonus, with normal cognition or subtle changes in executive function.1,2 In contrast to classic AD, MRI in these patients more frequently demonstrates abnormal signal and atrophy in the lower brain stem and upper cervical spine.1,2
- Farina L, Pareyson D, Minati L, et al. Can MR imaging diagnose adult-onset Alexander disease? AJNR Am J Neuroradiol 2008; 29: 1190-1196.
- Pareyson D, Fancellu R, Mariotti C, et al. Adult-onset Alexander disease: a series of eleven unrelated cases with review of the literature. Brain 2008; 131: 2321-2331.
Submitted by Philippe Rizek, MD and Niraj Kumar, MD, Dept. of Clinical Neurological Sciences, Western University, London, Ontario, Canada
Disclosures: Drs. Rizek and Kumar report no disclosures.