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

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.Arg142Glu) or c.563 C > T (p.Thr188Ile) or c.103G > C (p.Val35Leu) mutation in GJB1. The unique feature of this report is the identification of two novel mutations: c.563 C > T and sc.103G > C of the GJB1 gene detected in two families respectively. Another unique feature is that peripheral neuropathy symptoms in the three patients were insidious and found at the onset of CNS symptoms. CONCLUSIONS: Posterior leukoencephalopathy is involved in CMTX1 patients. The white matter changes in MRI of CMTX1 patients are reversible and recover later than CNS symptoms.