A Charcot-Marie-Tooth Disease Type 1J Case with Diffuse Thickening of Peripheral Nerves

Abstract

A 30-year-old woman presented with lumbar pain and numbness in her right foot, persisting for over 2 months. No signs of pes cavus or muscle atrophy were seen. EMG revealed an axonal and demyelinating neuropathy, characterized by a slowing of the motor conduction velocity, which ranged from 29.6 to 38.5 m/s. Sonographic and neuroimaging analyses revealed diffuse thickening of multiple peripheral nerves. The sural nerve and skin biopsy revealed chronic severe mixed peripheral neuropathy, with involvement of small fiber neuropathy. Her mother had a chronic progressive peripheral neuropathy characterized by pes cavus. These imaging findings and the family history prompted the genetic testing. We identified that both the proband and her affected mother carried a heterozygous ITPR3 pathogenic variant with c.4271C>T (p.T1424M) (Figure). Charcot-Marie-Tooth disease type 1J (CMT1J) is a rare autosomal dominant demyelinating peripheral neuropathy.1 Neuroimaging or ultrasound is an important supplementary tool for assessing neural morphology and structure.