Increased levels of GFAP in the cerebrospinal fluid in three subtypes of genetically confirmed Alexander disease.

GFAP levels in the CSF were highly elevated in three genetically confirmed cases of Alexander disease clinically conforming with infantile, early and late juvenile forms. No other CSF abnormalities were detected. Assay of CSF-GFAP may prove to be a rapid and cost-effective screening test in clinical variants of Alexander disease and an indicator of GFAP gene mutations.