A clinical review and histopathological study of three cases of Anderson-Fabry disease is presented and pathological changes in the central and peripheral nervous systems are reported, in some sites for the first time. These are telangiectatic changes in vessels of the sympathetic ganglia in the vertebral trunk; storage of glycolipid in pigmented cells of the substantia nigra and in anterior horn cells; and degeneration of nerve fibres in the dorsal root entry zone and substantia gelatinosa of the spinal cord. The histopathological findings suggest that in this disease pain is due to involvement of dorsal root ganglion cells with associated axonal degeneration of the small fibres in pathways subserving pain.