A RARE FORM OF ADULT-ONSET LEUKODYSTROPHY - ORTHOCHROMATIC LEUKODYSTROPHY WITH PIGMENTED GLIA

Background: Orthochromatic leukodystrophy with pigmented glia and scav enger cells is a rare leukodystrophy of unknown etiology. This report describes a 42-year-old man with a history of depression, dementia and parkinsonism having the pathological features of orthochromatic leuko dystrophy with pigmented glia. Methods: We reviewed the clinical histo ry and pathology of autopsy and brain biopsy material. Results: Imagin g revealed bilateral cerebral white matter hypodensities. At autopsy, the brain demonstrated a leukodystrophy affecting predominantly the ce rebral hemispheres and characterized by demyelination, and cytoplasmic pigment deposits in oligodendroglia and astrocytes. The pigment had t he staining properties of ceroid-lipofuschin and on ultrastructural ex amination was composed of membrane-bound lipid and electron-dense incl usions which had a fingerprint-like pattern. Similar pigment inclusion s were not observed on ultrastructural examination of renal, splenic o r hepatic tissue obtained at autopsy. The brain biopsy contained cereb ral cortex with sparse subcortical white matter in which a few oligode ndroglia and fewer astrocytes at the grey/white junctions showed cytop lasmic pigmentary inclusions identical to those described above. Howev er, due to the paucity of white matter in the specimen a definite diag nosis of orthochromatic leukodystrophy with pigmented glia was not mad e. Conclusions: The diagnosis of orthochromatic leukodystrophy with pi gmented glia and scavenger cells can only be made antemortem if the br ain biopsy contains adequate white matter and although a rare conditio n, it should be considered in the differential diagnosis of an adult o nset leukodystrophy.