Peripheral motor and sensory neuropathy of early childhood, simulating Werdnig-Hoffmann disease

Abstract

A five-year-old girl developed neurogenic muscular atrophy during infancy. On the basis of clinical findings and a muscle biopsy study a diagnosis of infantile spinal muscular atrophy, benign type II, was entertained. As the disease progressed, involvement of sensory pathways was detected by electrophysiological studies. Examination of a sural nerve specimen suggested a chronic polyneuropathy rather than spinal muscular atrophy. These findings were confirmed at autopsy by demonstrating severe loss of myelinated axons in ventral and dorsal spinal roots, peripheral nerves and dorsal columns of the spinal cord. In addition, islands of astroglial fibers were found in ventral and dorsal spinal roots, regarded as a secondary reaction to the breakdown of myelinated axons. This unusual scarring process seems to result from nerve fiber loss during the perinatal period, since radicular glial scar tissue is not known to occur in the spinal muscular atrophies of later onset. Examination of the sensory nervous system in patients with Werdnig-Hoffmann disease appears mandatory to clarify the precise disease entity leading to infantile neurogenic muscular atrophy.