Alzheimer type II glia

Assoc Prof Frank Gaillard ◉ ◈ et al.

Alzheimer type II glia are a type of glial cell. They are a pathological reactive astrocyte seen in the brain, unrelated to Alzheimer disease. They are seen most frequently in Wilson disease, but also in other systemic metabolic disorders, particularly those with elevated ammonia levels, typically due to hepatic impairment but sometimes also seen in other causes of systemic metabolic impairment, such as impaired renal function ^1,2.

They are seen in grey matter, particularly deep grey matter nuclei (e.g. putamina, globus pallidi and dentate nuclei) ^1,2.

Pathology

Microscopically these reactive astrocytes demonstrate enlarged pale nuclei, due to inconspicuous chromatin granules, with one or two sharply demarcated PAS-positive bodies adjacent to the nuclear membrane ¹. GFAP staining of the cell body is poor ². On electron microscopy, numerous mitochondria are evident ¹.