Herrera LOA; Ramírez RC; Infante FJ; Lavastida FH

Language: Spanish
References: 27
Page: 229-243
PDF size: 137.67 Kb.

ABSTRACT

Introduction: myotonia non-dystrophica is an important group of skeletal muscle channelopathies characterized by altered excitability of cell membrane. Nowadays are recognized many different clinical phenotypes with a severity level, ranging from severe neonatal myotonia with respiratory compromise to mild myotonic attack produced by periodical paralysis.
Objective: to analyze and discuss the physiopathology, clinical picture and diagnostic criteria of myotonia non-dystrophica less frequent in clinical practice.
Development: the specific genetic mutations in the chloride and sodium voltage channels are the cause in the majority of patients. Recent studies have allowed more precise correlations between genotype, electrophysiologic pattern and clinical phenotype. In addition each channelopathy diagnosis criterion is discussed.
Conclusions: despite significant advances in the clinic, molecular genetics and physiopathology of these disorders, there are important unresolved issues, such as the usefulness of neurophysiologic studies to identify possible genotype, the absence of a natural history on channelopathy currently, even when is available the study of molecular genetics, the association of myotonia congenita with myopathic changes, the relationship of myotonia congenita with congenital myopathies and finally the possibility of a more specific and appropriate treatment in the absence of randomized pharmacologic clinical trials to enable in the future treating and preventing ionic channels damage.

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