Clinical Features Of Mitochondrial Myopathy, Encephalopathy,Lactic Acidosis And Stroke-like Episodes Syndrome

Objectives We studied the clinical characteristics and therapies of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes(MELAS).Methods The clinical manifestations, biochemistry, imaging, pathology and genetics of6cases of MELAS were retrospectively analyzed. And then, we analyzed their treatments combining with the latest advances.Results The most common clinical manifestations were stroke-like episodes, limb weakness,seizure and cognitive dysfunction. The serum lactate levels were elevated in our patients, but no characteristic results were found in electroencephalography and Electromyography. All cases showed that the lesions indicated by CT or MRI were not distributed in accordance with cerebral vessels run. The first case of lesions showed increased and inverted lactate peak, and that elevated and decreased were mixed on the pathophysiology of stroke-like lesions using diffusion weighted imaging (DWI).Electron microscopic demonstrated increased numbers, size and unusual morphologies of mitochondria, some of which had crystalline "parking lot" inclusions. Ragged red fibers (RRF) were also discovered with Gomori trichrome, nicotinamide adenine dinucleotides reductase(NADH) and sdsuccinic dehydrogenase (SDH) stain in the former cases.2of them carried mtDNA A3243G mutation. Conclusions Since MELAS was characterized by multiple and complex clinical manifestations, the final diagnosis depended on muscle biopsy and gene detection.Imaging examination (especial MRS) can be valuable in early diagnosis of MELAS and differential diagnosis. Pharmacologic treatment, ketogenic diet and other therapies can help improve symptoms, but no radical cure.