Congenital Amyelinating Neuropathy: A Neuropathology Case Report and Review of Prior Cases

Abstract

Congenital hypomyelination/amyelination diseases of the peripheral nervous system can appear in the neonate or in late infancy with pathological findings of either hypomyelination or no myelination. Patients with these disorders most often present with severe hypotonia, weakness, delayed motor development, and frequently succumb to respiratory failure. The first reported case of congenital hypomyelination was described in 1969. Most cases have mutations in one of several genes encoding for proteins involved in peripheral nerve myelination (MPZ, PMP22, MTMR2 and Sox 10). Both familial and sporadic cases are reported. We describe here a case of an 18 year old female who had a long history of failure to thrive and developmental delays. She met all milestones for her development until about 5 years of age, when she began having difficulty maintaining normal weight. Her cardinal symptoms were chronic pain, autonomic instability, nutritional intolerance, developmental delay, and foot drop. She had no family history of similar neurological disease. Her neuropathological findings from sural nerve and skeletal muscle biopsies show amyelination, mild loss of large axons, and uniform atrophy of myofibers. This case represents one of the oldest living individuals with biopsy for amyelinating disease described in the literature.