Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)

TLDR

MNGIE presents with ophthalmoparesis, peripheral neuropathy, leukoencephalopathy, gastrointestinal dysmotility, and abnormal mitochondria in muscle. The study aimed to characterize the clinical, biochemical, and genetic features of eight patients with autosomal recessive MNGIE. The authors evaluated clinical presentations, performed biochemical assays, and conducted genetic analyses to delineate the disease. Brain MRI showed leukodystrophy in seven patients, nerve conduction and EMG revealed sensorimotor neuropathy with myogenic changes in two, muscle enzyme assays found partial cytochrome c oxidase defects in five patients (three.

Abstract

We studied the clinical, biochemical, and genetic features of eight patients with the autosomal recessive mitochondrial syndrome mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). MNGIE is clinically characterized by ophthalmoparesis, peripheral neuropathy, leukoencephalopathy, gastrointestinal symptoms (recurrent nausea, vomiting, or diarrhea) with intestinal dysmotility, and histologically abnormal mitochondria in muscle. Brain MRI scans were consistent with leukodystrophy in seven patients examined. Nerve conduction and EMG studies were compatible with a sensorimotor neuropathy; quantitative EMG of two patients suggested a myogenic process. Muscle mitochondrial enzyme analysis revealed a partial defect of cytochrome c oxidase activity in five patients; three had additional respiratory chain enzyme defects. Two patients had isolated complex I defects, and one had normal respiratory chain function. Southern blot analysis revealed multiple deletions of mitochondrial DNA in four of eight patients.