A clinical and natural history research on mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes / 中华神经科杂志

ABSTRACT

Objective To summarize the clinical features,natural history and causes of death of mitochondrial encephalomyopathy,lactic acidosis and stroke-like episodes (MELAS).Methods We retrospectively evaluated the clinical findings of 64 patients diagnosed as MELAS more than 3 years (death cases excluded) in Huashan Hospital from January 2005 to March 2017 and analyzed the natural course and the causes of death of the disease.Results Among 64 patients,the male-to-female ratio was 1.3 ∶ 1.Median onset age was 20.5 (16.8) years.The peak of incidence age was from 14 to 22 years.The most common features of MELAS in acute phase were seizures (48/64,75.0％),headache (41/64,64.1％),blurred vision (37/64,57.8％),nausea and vomiting (27/64,42.1％),fever (25/64,39.1％),mental and behavioral disorder (24/64,37.5％).Lactate dehydrogenase (31/60,51.6％),resting blood lactic acid (43/58,74.1％) and cerebral spinal fluid lactic acid (9/9) were elevated.Abnormal findings in electroencephalogram (36/40,90.0％),electrocardiogram (37/47,78.7％),electromyography (25/41,61.0％) were detected.In this cohort,20 patients (20/64,31.3％) with MELAS were dead.A Kaplan-Meier survival curve showed the estimated overall median survival time was 12 years.The median survival time of the group onset before sex maturity (≤ 14 years) was 8 years and that in the group onset after sex maturity (＞ 14 years) was 21 years.The causes of death were cardiogenic incidence (4/20,20.0％),pulmonary infection (4/20,20.0％),lactic acidosis (2/20,10.0％) and status epilepticus (2/20,10.0％).Conclusions MELAS is usually presented in young people associated with high mortality rate.The leading causes of death are cardiogenic,pulmonary infection and lactic acidosis.