[Lipidic myopathies]

The lipid storage myopathies are produced by a biochemical defect that directly or indirectly interferes with the metabolism of fatty acids in the muscle fiber. The oxidation of fatty acids is performed by enzymes lying in the mitochondrial membranes and matrix. The phenotype is very similar between the different biochemical defects, presenting with two large groups: One with early-onset, metabolic crisis and multisystemic failure, and one with late-onset, predominant myopathy and myoglobinuria. The diagnosis of these disorders has advanced significatively in the last ten years, permitting their classification at molecular level according to the biochemical and genetic defect.