Abstract
Mitochondrial encephalopathy, lactic acidosis, and stroke-like episode (MELAS) syndrome is one of mitochondrial encephalopathy. As the early clinical manifestations can be variable, it is important to suspect the disease, especially in patients with multiple organ dysfunctions. A boy was diagnosed with epilepsy when he was 9 years old. Two years later, severe headache and blurred vision developed suddenly. On examination, left homonymous hemianopsia was detected with corresponding cerebral parenchymal lesions in right temporo-occipito-parietal areas. MELAS syndrome was confirmed by genetic test, which showed m.3243 A>G mitochondrial DNA mutation. Multivitamins including coenzyme Q10 were added to anticonvulsant. He experienced 4 more events of stroke-like episodes over 5 years, but he is able to perform normal daily activities. A 13-year-old boy was brought to the hospital due to suddenly developed respiratory arrest and asystole associated with pneumonia. Past medical history revealed that he had multiple medical problems such as epilepsy, failure-to-thrive, optic atrophy, and deafness. He has been on valproic acid as an anticonvulsant which was prescribed from local clinic. He recovered after the resuscitation, but his cognition and motor function were severely damaged. He became bed-ridden. He was diagnosed with MELAS syndrome by brain MRI, muscle biopsy, and clinical features. Genetic test did not reveal any mitochondrial gene mutation. Four years later, he expired due to suddenly developed severe metabolic acidosis combined with hyperglycemic hyperosmolar nonketotic coma. The clinical features of MELAS syndrome are variable. Early diagnosis before the presentation to the grave clinical course may be important for the better clinical outcome.
멜라스 증후군은 사립체 질환 중의 하나로서, 증상발현 시기 및 임상 양상이 매우 다양하여 의심하지 않으면 진단이 늦어지는 경우가 있을 수 있다. 연구자들은 임상경과를 달리하는 두 증례를 경험하였기에 보고하는 바이다. 증례 1에서는 두통과 시야 흐림, 경련 등이, 증례 2에서는 성장장애, 난청, 시야 흐림, 경련 등이 초기 증상으로 나타났으며, 증례 1은 현재도 일상 생활이 가능한 정상적인 활동도를 보이는 반면에, 증례 2의 경우에는 심각한 뇌손상을 받은 후에 진단되어 예후가 불량하였다. 멜라스 증후군의 치료는 대증적으로 이루어지게 되며, 약물적인 치료 중 코엔자임 Q10, L-아르지닌 등을 사용하였을 때 성공적인 결과를 얻을 수 있다. 질환의 초기에는 비특이적인 경우가 많음으로 관심과 의심을 통하여 멜라스 증후군을 조기 진단하는 것이 매우 중요하다고 할 수 있으며, 조기 진단과 적절한 교육 및 지지적인 치료를 통해 임상경과를 좋게 만들 수 있도록 노력하는 것이 예후에 중요하다고 할 수 있겠다.