Sensory ganglioneuropathy in infantile spinal muscular atrophy. Light and electronmicroscopic findings in two cases.

Light and electronmicroscopic findings in two cases. Neuropediatrics 12: 215-31 (1981). Two cases of infantile spinal muscular atrophy (Werdnig-Hoffmann disease) are described in unrelated children deceased at 11 months (acute clinical onset at 6 months) and 2 years (onset at birth). Severe respiratory difficulties, hypotonia, muscular weakness and depressed tendon reflexes were the main clinical features. Bulbar palsy, bilateral ptosis, pale optic discs and atactic movements of the hands were observed in the child deceased at 11 months. Besides severe loss of anterior horn cells and neurogenic muscle atrophy there was evidence of an extensive sensory involvement in both cases. Shrinkage, vacuolation as well as chromatolytic changes of dorsal root ganglion cells, together with the evidence of a primary axonal damage in sural nerve biopsies were interpreted in terms of ganglioneuropathy of the primary sensory neurons. An invasion of fibrous astrocytes into dorsal roots constituted another striking anomaly in one case as well as a pronounced degeneration of cranial nerves V and VIII in the other case, a finding not hitherto reported in Werdnig-Hoffmann disease.