Histopathological features of a patient with Charcot-Marie-Tooth disease type 2U/AD-CMTax-MARS.

Abstract

Charcot-Marie-Tooth (CMT) disease is a complex of peripheral nervous system disorders. CMT type 2U (CMT2U) is an autosomal dominant (AD) disease caused by mutations in the MARS gene encoding methionyl-tRNA synthetase; this disease has thus been newly called AD-CMTax-MARS. A few families with mutations in the MARS gene have been reported, without detailed histopathological findings. We describe a 70-year-old woman who had bilateral dysesthesia of the soles since the age of 66 years. Sural nerve biopsy showed a decrease in the density of large myelinated nerve fibers. Increased clusters of regenerating myelinated nerve fibers were noted. Electron microscopic analyses revealed degeneration of unmyelinated nerves. There was no vasculitis or inflammatory cell infiltration. Genetic analysis identified a heterozygous p.P800T mutation, a reported mutation in the MARS gene. We report the detailed histopathological findings in a patient with CMT2U/AD-CMTax-MARS. The findings are similar to those found in CMT2D caused by mutations in the GARS gene, encoding glycyl-tRNA synthetase.

• Authors: Makito Hirano, Nobuyuki Oka, Akihiro Hashiguchi, Shuichi Ueno, Hikaru Sakamoto, Hiroshi Takashima, Yujiro Higuchi, Susumu Kusunoki, Yusaku Nakamura
• Journal: Journal of the peripheral nervous system : JPNS (J Peripher Nerv Syst) Vol. 21 Issue 4 Pg. 370-374 (12 2016) ISSN: 1529-8027 [Electronic] United States
• PMID: 27717217 (Publication Type: Case Reports, Research Support, Non-U.S. Gov't)
• Copyright: © 2016 Peripheral Nerve Society.

Chemical References

• Methionine-tRNA Ligase

Topics

• Aged
• Charcot-Marie-Tooth Disease (genetics, pathology)
• Female
• Genetic Testing
• Humans
• Methionine-tRNA Ligase (genetics)
• Microscopy, Electron
• Mutation (genetics)
• Neural Conduction (genetics)
• Sural Nerve (physiopathology, ultrastructure)