Purpose: Mitochondrial diseases have numerous phenotypic expression, and form an heterogeneous group of genetic diseases in which the production of energy fails. Well known in childhood, these mitochondrial diseases can onset in adulthood and may remain unrecognized. We propose a recent review (Medline 1981-2001) of the literature on adult forms of mitochondriopathies, illustrated with a typical case report.
Current knowledge and key points: Mitochondrial diseases have numerous phenotypic expression in adulthood. Principles of diagnosis are i) recognize a phenotype, ii) prove the mitochondrial abnormalities, iii) realize a genetical analysis. Main varieties of adult phenotypes are studied and separated in 1) skeletal muscular involvement, ocular myopathies above all; 2) mitochondrial cardiomyopathies; 3) neurological involvement (MERRF, MELAS, NARP, MNGIE syndromes); 4) endocrinological involvement and diabetes mellitus; 5) multisystemic diseases with a particular focus on Kearns Sayre syndrome.
Future prospects and projects: Phenotypic analysis of a patient with mitochondrial disease is not simple. A "multi-tissues" involvement is the main characteristic feature. Faced with such patients, replacement therapy, genomic therapy and genetic advice are evoked.