Multiple Sclerosis Linked to Charcot-Marie-Tooth Disease, Study Finds

Persons with X-linked Charcot-Marie-Tooth disease (CMTX) may have an increased risk of also having multiple sclerosis (MS), according to the results of a newly published study.

Given that 4 cases have been published of patients with CMTX developing demyelination of the central nervous system (CNS) characteristic of MS, the authors of the study set out to systematically investigate the connection between the 2 conditions.

In total, 70 patients (36 men and 34 women) with mutations in GJB1 on the X chromosome—the genetic cause of CMTX—were followed for 20 years at the neurogenetics unit of Eginition Hospital at National and Kapodistrian University of Athens, Greece, and were monitored for MS features using magnetic resonance imaging (MRI) and serum testing. The researchers also included 18 patients with CMTX without CNS symptoms and 18 matched control patients.

The researchers identified 3 patients (2 men and 1 woman) with CMTX in whom the signs and symptoms of MS had manifested over the 20 years. In addition, among the 18 patients with CMTX but no MS symptoms, 10 had brain MRI findings showing lesions suggestive of focal demyelination, compared with none of the control patients.

“We have demonstrated a higher than expected frequency of MS in patients with CMTX and identified incidental focal demyelinating lesions on brain MRI in patients with CMTX without CNS symptoms,” the authors wrote. “This provides circumstantial evidence for GJB1 mutations acting as a possible MS risk factor,” they concluded.

—Michael Gerchufsky

Reference:

Koutsis G, Breza M, Velonakis G, et al. X linked Charcot-Marie-Tooth disease and multiple sclerosis: emerging evidence for an association [published online September 8, 2018]. Neurogenetics. http://dx.doi.org/10.1136/jnnp-2018-319014.