[A case of hereditary motor and sensory neuropathy (HMSN) with excessive myelin outfolding with autosomal recessive inheritance].
A 3-year-old girl with rare and unique myelin abnormality in the sural nerve is described. Her parents are first cousins. Her clinical features were similar to those of HMSN I. Therefore, a diagnosis of autosomal recessive form of HMSN was made. However, in histopathologic studies of the sural nerve, it was observed that the folded myelin did not extend into the axon but into the outer portion of Schwann cell cytoplasm, so called excessive myelin out folding. The density of both the myelinated and unmyelinated fibers was less in the patient than in controls. In recent years, the patient described above is usually classified under HMSN IVB or (Charcot-Marie-Tooth disease) CMT4B, and molecular genetic studies are now in progress.
Ohnishi
A
A
Department of Neurology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
Narazaki
O
O
Hanai
T
T
D002675:Child, Preschool; D005260:Female; D005808:Genes, Recessive; D015417:Hereditary Sensory and Motor Neuropathy / Q000235:genetics* / Q000473:pathology; D006801:Humans; D009186:Myelin Sheath / Q000648:ultrastructure*; D013497:Sural Nerve / Q000648:ultrastructure