A Case Report and Literature Review of Charcot-Marie-Tooth Disease Type 2F in a Family.

OBJECTIVE

To report the clinical and genetic characteristics of a rare Charcot-Marie-Tooth disease type 2F (CMT2F) pedigree, and to explore the phenotypic diversity and diagnostic essentials of the mutation in combination with literature review.

METHODS

The clinical data, electrophysiological findings, and genetic testing results of the proband and pedigree members were retrospectively analyzed, and relevant literatures were reviewed for comparative analysis.

RESULTS

Both patients had an onset in middle and old age (50/66 years), presenting with distal lower limb muscle weakness (Grade III), muscle atrophy, absent tendon reflexes, pes cavus, and sensory abnormalities. Serum creatine kinase (CK) was elevated (474 U/L), and electromyography indicated axonal peripheral nerve damage. Genetic testing revealed a heterozygous mutation of HSPB1 gene c.418C>G [p.Arg140Gly], which was verified by co-segregation in the pedigree. Literature review showed that this mutation causes axonal transport dysfunction by impairing the chaperone function of HSP27.

CONCLUSION

This study expands the phenotypic spectrum of late-onset CMT2F, with some patients showing mild elevation of serum CK. It provides new clinical evidence for the pathogenicity of this mutation.