Metabolic myopathies

Abstract

This article presents an overview of the clinical and biochemical classification and the evaluation of metabolic myopathies has been done. A special effort has been made to classify the conditions according to their clinical presentation. Four groups of metabolic myopathies are described: progressive muscle weakness, exercise intolerance with cramps and myoglobinuria (myophosphorylase deficiency phenotype), exercise intolerance with cramps and myoglobinuria (carnitine palmityltransferase (CPT) II deficiency phenotype), and myopathy as a manifestation of multisystem disease (mitochondrial myopathies). Approach to diagnosis, clinical aspects, laboratory findings, and available treatments are discussed. We have developed a database in which more than 150 neurometabolic conditions are described in detail, many of them having myopathy as their main clinical symptom. By using the searching capabilities of the software, conditions are searched by age of onset, symptoms, signs, and laboratory findings, helping to find the most probable diagnosis in an affected child and its current recommended management.