Incongruent electrodiagnostic and sonographic evaluations of a trifid median nerve in carpal tunnel syndrome

Demyelinating motor neuropathy associated with a homozygous GPT2 pathogenic variant

“…A trifid median nerve is a rare atypical variant, with few cases reported in the literature. [1][2][3][4][5][6][7] While prior case reports have used neuromuscular ultrasound to identify the presence of a trifid median nerve, these studies have not consistently included associated electrodiagnostic testing and specific neuromuscular ultrasound measurements, such as median nerve cross-sectional area (CSA), Δ CSA (from the level of the pronator quadratus to the level of the carpal tunnel inlet), or wrist-to-forearm ratio in their evaluation for carpal tunnel syndrome (CTS). The author presents a case of a trifid median nerve, with specific electrodiagnostic and ultrasound measurements, and assesses whether our current ultrasound parameters for more commonly encountered bifid median nerves apply to a trifid median nerve.…”

“…Preclinical studies in Gpt2-null mice confirmed that Gpt2 plays a role in amino acid metabolism and the Krebs cycle with reduced contribution of glutamine-related anaplerosis. 1 GPT2 mutations were described in 46 patients [1][2][3][4][5][6][7] with moderate to severe intellectual disability and microcephaly, often associated with early-onset spastic paraplegia. Here, we describe a patient with a novel homozygous nonsense GPT2 pathogenic variant associated with a syndromic peripheral neuropathy.…”