RESUMEN
Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes syndrome (MELAS) is a maternally inherited multisystem disease caused by mutations of the mitochondrial DNA. The characteristic clinical features are: encephalopathy manifesting as dementia and seizures, stroke-like episodes at young age (usually < 40), lactic acidosis and myopathy with ragged-red fibres. Other frequent manifestations include: sensorineural deafness, diabetes, hypoparathyroidism, peripheral neuropathy and cardiomyopathy. We present two patients with MELAS who were diagnosed 4 and 9 years respectively following the onset of the disease despite the characteristic clinical pictures. The differential diagnostics of inborn and acquired disorders causing stroke is included. We regard that mitochondrial diseases are still insufficiently known and are frequently misdiagnosed. The knowledge is indispensable for establishing diagnosis and accurate genetic counselling. Although there is no specific therapy for mitochondrial diseases to date, coenzyme Q and various vitamins as well as moderate degree exercise might be recommended.
Asunto(s)
Síndrome MELAS/diagnóstico , Síndrome MELAS/genética , Adolescente , Adulto , Deficiencia de Citocromo-c Oxidasa/genética , ADN Mitocondrial/genética , Diagnóstico Diferencial , Femenino , Humanos , Síndrome MELAS/patología , Imagen por Resonancia Magnética , Masculino , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/patología , Factores de Tiempo , Tomografía Computarizada por Rayos XRESUMEN
Leber hereditary optic neuropathy (LHON), which is a relatively rare disease, is an inherited form of bilateral atrophy of optic nerves. This atrophy is related to degeneration of retinal ganglion cells and optic nerve axons. The aetiology of this disease is complex and involves primary mutations of mitochondrial DNA, as well as secondary genetic and/or epigenetic changes. We compared the clinical course of LHON in the patients with identical mitochondrial mutations. The molecular PCR-diagnosis was performed in 8 patients, representing 2 generations of the tested family. The group included 2 women suspected of being carriers and 6 men, 3 of whom were diagnosed with LHON and 3 suspected of being at risk of LHON. The primary 11,778 mtDNA mutation was diagnosed in all tested patients with one exception of the son of a male with LHON, which is in agreement with inheritance of mtDNA mutations.