Alexander's disease presenting as astrocytoma.

A case of progressive fibrinoid degeneration of astrocytes is described. Symptoms began with convulsions at the age of 6 weeks and cerebral tumour was suspected because of enlargement of the head, increased intracranial tension, and marked proliferation of astrocytes in the brain biopsy which was interpreted as an astrocytoma. Fibres and granules staining deeply with PTAH are a constant feature of the few cases so far described. The aetiology is unknown but an inherited metabolic defect of astrocytes may be responsible.