Clinical Study On Mitochondrial Encephalomyopathy In 11 Subjects

Objective:Mitochondrial encephalomyopathy is a series of diseases that drag in central nervous system and generalized muscles.The pathogenesis of the disease is lack of ATP for the dysfunction of mitochondria.The misdiagnosis rate of the disease is high and the purpose of this study is to improve the recognition and diagnosis of mitochondrial encephalomyopathy and thus, clinicians could take rational treatment in time and improve patients’prognosis.Methods:The clinical data of 11 patients with mitochondrial encephalomyopathy were analyzed together with the physical data,clinical presentations, laboratory data,neuroimaging findings, muscle biopsy, genetic testing,treatment and prognosis. Reviewing literature and summarizing the clinical characteristic of mitochondrial encephalomyopathyResults:Among the 11 patients with mitochondrial encephalomyopathy,6 cases were male patients and 5 cases were female. The age range of 11 patients was 5-41 years old, and the mean age was 17 years old.1 case had family history.7 cases were misdiagnosed in the first clinic visit.The onset of the 11 cases,9 were paroxysmal and 2 were hidden.The clinical manifestations of the disease are varied.In the course,10 cases had an epileptic seizure,2 cases failured to thrive,8 cases had a headache,8 cases had limb weakness,6 cases had reaction ability, cognitive function or mental decline,6 cases had decreased vision,2 cases had hearing impairment,2 cases had trouble with speaking clearly or asyndesis,2 cases had mental symptoms.Among the 9 cases who took the determination of serum lactate,8 was in high level.9 cases had MRI examination and all found abnormality, which showed intracranial multiple long Tl and long T2 signals, FLAIR show high signal and the lesions are not in a vascular distribution area.10 patients had EEG examination, and 9 cases were present slow activities increased, epileptiform discharges were detected.6 cases had muscle biopsy and all found the ragged red fiber(RRF). 6 cases had molecular genetic testing, and all found A> G pathogenic mutations in mitochondrial DNA m.3243 sites. Among the 10 cases who had an epileptic seizure,3 cases can be controlled with single kind of antiepileptic drug. The other 7 cases had a recurrence of epilepsy with single kind of antiepileptic drugs, but can be cotrolled after drug adjusting or drug combination. Among these patient,1 had a recurrence after discharge,and 1 died for exacerbation. The case with muscle strength decline still present a progressive strength decreasing after treatment for symptomatic support.Conclusion:Mitochondrial encephalomyopathy is often accompanied by seizure, which is usually found in children, and also often accompanied by systemic muscle symptoms.The clinical manifestations of the disease is not typical, but is complex and varied symptoms, so the clinical misdiagnosis rate is high. Mitochondrial encephalomyopathy mainly involves the main intracranial artery distribution area (parietal lobe, temporal lobe, occipital lobe, etc.) in central nervous system, and can involve more than one part. Patients with mitochondrial myopathy brain are usually detected the elevation of serum lactate levels, but if the lactic acid level is normal, it does not rule out the possibility of the disease,The confirmation of the disease is mainly by muscle biopsy or genetic tests. There is no specific treatment for mitochondrial encephalomyopathy till now, and it still give priority to symptomatic treatment.And the prognosis is poorer.