A New Mitochondria-Related Disease Showing Myopathy with Episodic Hyper-creatine Kinase-emia

作者:Okamoto Yuji; Higuchi Itsuro; Sakiyama Yusuke; Tokunaga Shoko; Watanabe Osamu; Arimura Kimiyoshi; Nakagawa Masanori; Takashima Hiroshi*
来源:Annals of Neurology, 2011, 70(3): 486-492.
DOI:10.1002/ana.22498

摘要

Objective: To elucidate the relationship between mitochondrial DNA (mtDNA) alterations and a mitochondrial disease with a distinct combination of characteristic symptoms, namely episodic hyper-creatine kinase (CK)-emia and mild myopathy.
Methods: We selected 9 patients with mtDNA np8291 alteration from 586 patients suspected to have a mitochondrial disease, and assessed them clinically, pathologically, and genetically. These 9 patients had undiagnosed mitochondrial myopathy with episodic hyper-CK-emia, all showing similar symptoms and progression.
Results: Patients had mild muscle weakness and episodic hyper-CK-emia triggered by infections or drugs. Five of 9 patients were initially diagnosed with other conditions, such as myasthenia gravis, polymyositis, viral myositis, and drug-induced myopathy, because these conditions were acute or subacute, and 9 patients showed the same 16 mtDNA alterations, which have been reported to be nonpathological polymorphisms. Muscle biopsy revealed ragged-red fibers, highly expressed succinate dehydrogenase staining fibers, and cytochrome c oxidase-deficient fibers. Because their mitochondrial sequence data was almost the same, and 9 patients live in widely separated cities in Japan, the alterations may have arisen from a single source.
Interpretation: These findings suggest that mild myopathy with episodic hyper-CK-emia associated with some of the 16 mtDNA alterations or at least with their mitochondria, could be a novel mitochondrial disease. Therefore, we propose that this disease be named as "mitochondrial myopathy with episodic hyper-CK-emia (MIMECK).'' These alterations could work concomitantly and probably modify the impact of medications or other environmental factors. We believe these findings provide an insight into a novel aspect of mitochondrial disease pathogenesis. ANN NEUROL 2011;70:486-492

  • 出版日期2011-9