Recurrent episodes of reversible posterior leukoencephalopathy in three Chinese families with GJB1 mutations in X-linked Charcot-Marie-tooth type 1 disease: case reports

Abstract

Background The X-linked form of Charcot-Marie-Tooth disease type 1(CMTX1) is an inherited peripheral neuropathy that arises in patients with mutations in the gap-junction beta-1 gene (GJB1). Case presentation Three young male patients from Southern China with pes cavus experienced multiple episodes of transient central nervous system (CNS) dysfunction. Three patients all had reversible posterior leukoencephalopathy as detected by brain diffusion-weighted magnetic resonance imaging (MRI-DWI). Nerve conduction velocity (NCV) showed sensorimotor polyneuropathy with mixed demyelinating and axonal features. Genetic testing indicated a c.425G>A (p. Arg 142 Glu) or c.563 C>T (p. Thr 188 Ile) or c.103G>C (p. Val 35 Leu) mutation in GJB1. The unique feature of this report is two novel mutations: c.563 C>T and sc.103G>C of GJB1 gene detected in two families respectively. Another unique feature is that peripheral neuropathy symptoms in three patients were insidious and found at the onset of CNS symptoms Conclusions Central nervous system involvement in patients with CMTX1 indicates that myelin damage in the CNS and peripheral nerve system may have similar pathogenetic mechanisms.