RESUMO
Our knowledge of mitochondrial respiratory chain diseases has increased dramatically in recent years, but relatively little information is available about their prevalence and incidence, either in pediatric or adult patients. This study reports incidence and prevalence estimates, and summarizes the clinical, biochemical, histologic, and genetic characteristics of 51 patients age 0-16 years. The overall annual incidence of all mitochondrial respiratory chain diseases was estimated to be 1.43 cases per 10(5) in the population as a whole, and 2.85 cases per 10(5) in the under-6 population. The overall prevalence of all mitochondrial respiratory chain diseases was estimated as 7.5 cases per 10(5) in the under-19 population, and 8.7 cases per 10(5) in the under-16 population. These incidence and prevalence estimates are higher than in most previous studies of pediatric populations. Estimated prevalences of specific mitochondrial respiratory chain diseases were 2.05 cases per 10(5) for Leigh syndrome, 0.68 per 10(5) for mitochondrial deoxyribonucleic acid (mtDNA) deletions and deletions-duplications, 1.59 per 10(5) for mtDNA depletions, and 0.45 per 10(5) for mtDNA point mutations. Leigh syndrome was the most frequent clinical syndrome. The estimates of the prevalences of mtDNA deletions, deletions-duplications, and point mutations set forth here are lower than in similar previous studies, whereas the estimate of the prevalence of mtDNA depletions is rather higher. Sixteen of these patients manifested phenotypic syndromes that have not been previously reported in association with mitochondrial respiratory chain diseases.
Assuntos
Doenças Mitocondriais/epidemiologia , Adolescente , Criança , Pré-Escolar , Deleção Cromossômica , Estudos Transversais , DNA Mitocondrial/genética , Diagnóstico Diferencial , Feminino , Humanos , Incidência , Lactente , Doença de Leigh/diagnóstico , Doença de Leigh/epidemiologia , Doença de Leigh/genética , Masculino , Doenças Mitocondriais/diagnóstico , Doenças Mitocondriais/genética , Encefalomiopatias Mitocondriais/diagnóstico , Encefalomiopatias Mitocondriais/epidemiologia , Encefalomiopatias Mitocondriais/genética , Fenótipo , Mutação Puntual , EspanhaRESUMO
We report an infant with complex I deficiency of the mitochondrial respiratory chain whose most conspicuous symptom at presentation was an Ohtahara syndrome. Review of the literature suggest that association of these two conditions is extremely rare. Despite the few cases reported, in our view Ohtahara syndrome should be considered as one of the forms of presentation of mitochondrial dysfunction.