ABSTRACT
PURPOSE: Leber's hereditary optic neuropathy (LHON) presents in early adulthood with painless progressive blindness of one or both eyes. Usually there is a positive family history of similar disease on the maternal side. Definitive diagnosis can be established by finding the change in the mitochondrial gene. No molecular studies have been reported from India. MATERIAL AND METHODS: Clinical, ophthalmologic and molecular studies were carried out in two patients from different families and available first degree relatives. The subjects were tested for the three common mutations seen in LHON by molecular techniques of polymerase chain reaction using mutation specific primers. RESULTS: The mutations G3460A and G11778A in the mitochondrial genes MTND1 and MTND4, known to be causative for LHON, were found in one family each. CONCLUSION: Diagnosis of LHON should be considered in familial cases and in young adults with optic atrophy. Confirmation of diagnosis should be sought by molecular gene analysis. Genetic counselling should be offered to all 'at risk' relatives of a patient harbouring the mutation.
Subject(s)
Adolescent , DNA, Mitochondrial/genetics , Humans , India , Male , Mutation , NADH Dehydrogenase/genetics , Optic Atrophy, Hereditary, Leber/diagnosis , Pedigree , Polymerase Chain ReactionABSTRACT
CONTEXTO: A neuropatia óptica hereditária de Leber representa uma importante causa de perda visual progressiva, sem dor, em pacientes jovens do sexo masculino. OBJETIVO: Relatar o caso de um paciente jovem com quadro clínico e neurofisiológico sugestivo de neuropatia óptica hereditária de Leber, confirmado pelo teste genético. RELATO DE CASO: Jovem do sexo masculino com 17 anos de idade com perda visual bilateral progressiva tinha história familiar de perda visual progressiva em dois tios maternos. O paciente tinha antecedentes de tabagismo e alcoolismo pesado. O exame neuro-oftalmológico demonstrou acuidade visual de 20/800 em ambos os olhos, com diminuição dos reflexos pupilares direto e consensual e palidez de papilas ópticas no exame de fundo de olho. O exame de potencial visual evocado definiu distúrbio de condução em ambos os nervos ópticos. O exame de campimetria visual revelou perda visual completa em todos os campos visuais de ambos os olhos. O paciente foi diagnosticado com neuropatia óptica bilateral, com a suspeita clínica de neuropatia óptica hereditária de Leber, e o estudo genético para a avaliação das principais mutações encontradas nesta doença revelou a presença da mutação homoplásmica 11778, confirmando, desta forma, o diagnóstico de neuropatia óptica hereditária de Leber.
Subject(s)
Humans , Male , Adolescent , DNA, Mitochondrial/genetics , Optic Atrophy, Hereditary, Leber/diagnosis , Optic Atrophy, Hereditary, Leber/genetics , DNA Mutational Analysis , Point Mutation , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , PrognosisABSTRACT
A young Thai male presented with bilateral visual loss and disc pallor. The 14484 mutation responsible for Leber's hereditary optic neuropathy (LHON) was identified on blood mitochondrial analysis. His visual loss was more severe than the visual loss described in Caucasian and Japanese patients and showed no improvement. He had no other identifiable mutations related to LHON nor any associated neurological disorder. This is the first case report of LHON with the 14484 mutation in a Thai patient.