A rare case of proximal dominant hereditary motor and sensory neuropathy with TFG mutation

Abstract

Hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) or Okinawa type is a rare neuromuscular disorder characterized by proximal dominant neurogenic atrophy and distal sensory changes with an autosomal dominant pattern of inheritance. The disease is characterized by adult-onset proximal weakness and atrophy, muscle cramps, fasciculations, areflexia, elevated creatine kinase, hyperlipidemia, and diabetes and is similar to Kennedy’s disease, but differs in that the mode of inheritance is autosomal dominant. We present a 53-year-old male patient with symmetrical proximal weakness, fasciculations, absent patellar tendon reflexes, and a positive family history for the same symptoms suggestive of HMSN-P, as well as his clinical, electrophysiological, and genetic features. These findings led to a genetic test that identified a variant in the TFG gene (c. 854C>T (p.Pro 285Leu)) and confirmed the diagnosis of HMSN-P. This case demonstrates the importance of considering this rare differential diagnosis in patients with proximal muscle weakness and distal sensory deficits with progressive muscle cramps.