Metabolic myopathies: the challenge of new treatments.

The recognition of a series of metabolic/enzymatic dysfunction in metabolic myopathies has allowed new therapeutic advances. The most recent ones are enzymatic replacement therapy (ERT) in glycogenosis type II in both the infantile, juvenile and the adult forms, targeted manipulation of diet that has been tried in glycogenosis type II (Pompe disease), type V (McArdle's disease), and in Carnitine palmitoyl transferase 2 (CPT 2) deficiency, a rare disorder of fatty acid oxidation. A well known hypolipidemic drug, bezafibrate, has been tested to stimulate expression of mutated gene for CPT 2, but it may represent a challenge for a series of other fatty acid mitochondrial disorders to restore the capacity for normal long-chain fatty oxidation in muscle. The present review summarizes the most recent clinical achievements that have achieved the interest for an accurate and early diagnosis of these metabolic disorders.