Abstract
Mitochondrial disorders are highly heterogeneous and can manifest as a spectrum of clinically heterogeneous disorders that affect multiple organ systems. Herein, we report a Chinese female patient carrying mitochondrial DNA m.3243A>G mutation who sequentially experienced myoclonic epilepsy with ragged red fibers, mitochondrial neurogastrointestinal encephalomyopathy, and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes. This report expands the current understanding of phenotypic heterogeneity in mitochondrial disorders.