Dramatic improvement of myotonia permanens with flecainide: a two-case report of a possible bench-to-bedside pharmacogenetics strategy

Jean-François Desaphy,Diana Conte Camerino,Anna Modoni,Mauro Lomonaco

doi:10.1007/s00228-012-1414-3

Abstract

Dramatic improvement of myotonia permanens with flecainide: a two-case report of a possible bench-to-bedside pharmacogenetics strategy

Highlights

We report the case of a mother and her son, both carrying the G1306E sodium channel mutation associated with a severe phenotype of myotonia permanens and little improvement with mexiletine
The proband came to our observation when she was 20 years old, complaining since early childhood of severe and painful generalized muscle stiffness, exacerbated after exercise, in wet weather and during febrile episodes
There are only a few reports on myotonia permanens associated with G1306E mutation, including a familial case with autosomal dominant inheritance [7]

Summary

Introduction

We report the case of a mother and her son, both carrying the G1306E sodium channel mutation associated with a severe phenotype of myotonia permanens and little improvement with mexiletine. The proband came to our observation when she was 20 years old, complaining since early childhood of severe and painful generalized muscle stiffness, exacerbated after exercise, in wet weather and during febrile episodes. He shows a very severe phenotype, including facial and ocular muscle myotonia since his birth, generalized painful muscle myotonia, and muscle hypertrophy.

Results

Conclusion