Treatment of a patient with severe lactic acidosis and multiple organ failure due to mitochondrial myopathy:A case report

BACKGROUND Mitochondrial myopathy is a rare genetic disease with maternal inheritance that may involve multiple organ systems.Due to the lack of typical characteristics,its clinical diagnosis is difficult,and it is often misdiagnosed or even missed.CASE SUMMARY The patient was a young college student.When he presented at the hospital,he had severe lactic acidosis,respiratory failure,and shock with multiple organ dysfunction syndrome(MODS).He was treated by mechanical ventilation,venoarterial extracorporeal membrane oxygenation,and other organ support.However,his condition continued to worsen.After a thorough and detailed medical and family history was taken,a mitochondrial crisis was suspected.A muscle biopsy was taken.Further genetic testing confirmed a mitochondrial gene mutation(TRNL13243A>G).The final diagnosis of mitochondrial myopathy was made.Although there is no known specific treatment,intravenous methylprednisone and intravenous immunoglobulin were started.The patient’s shock eventually improved.The further course was complicated by severe infection in multiple sites,severe muscle weakness,and recurrent MODS.After 2 mo of multidisciplinary management and intensive rehabilitation,the patient could walk with assistance 4 mo after admission and walk independently 6 mo after admission.CONCLUSION More attention should be paid to mitochondrial myopathy to avoid missed diagnosis and misdiagnosis.

THE PATHOGENESIS OF EXPERIMENTAL MODEL OF MITOCHONDRIAL MYOPATHY INDUCED BY GERMANIUM DIOXIDE

Objective. The purpose of the study was to build up an animal model of mitochondrial myopathy in order to analyse the pathogenesis of the disease. Methods. The skeletal muscles from Wistar rats treated with germanium dioxide for 24 weeks were analysed by histopathologic and electron- microscopic studies. A quantitative analysis was carried out in mitochondrial DNAs of these samples. The biological function of the model was determined. Results. An animal model of mitochondrial myopathy was built up, in which oxygen free radicals were increased and mitochondrial DNA copies were decreased contrasted with controls. Conclusion. It suggested that environmental toxin may play a role in the pathogenesis of mitochondrial myopathy. The increase of oxygen free radicals is an important link causing the disease.

Sciatic Nerve Block with Ropivacaine and Prilocaine in a Patient with Chronic Progressive External Ophthalmoplegia(CPEO)

The anesthetic implications of caring for patients with mitochondrial myopathies (MM) are not well defined, and the few case reports that have been published are contradictory. Local anesthetics particularly have the potential to worsen neuromuscular manifestations via direct effects on mitochondrial bioenergetics. Here we describe the anesthetic management of a patient with chronic progressive external ophthalmoplegia (CPEO) in which a sciatic nerve block with ropivacaine and prilocaine was performed and review the available related literature.

Progress in Diagnosing Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like Episodes

Objective： Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes （MELAS） is a progressive, multisystem affected mitochondrial disease associated with a number of disease-related defective genes. M ELAS has unpredictable presentations and clinical course, and it can be commonly misdiagnosed as encephalitis, cerebral infarction, or brain neoplasms. This review aimed to update the diagnosis progress in MELAS, which may provide better understanding of the disease nature and help make the right diagnosis as well. Data Sources： The data used in this review came fi-om published peer review articles from October 1984 to October 2014, which were obtained fiom PubMed. The search term is ＂MELAS＂, Study Selection： lnfornmtion selected from those reported studies is mainly based on the progress on clinical tkatures, blood biochemistry, neuroimaging, muscle biopsy, and genetics in diagnosing MELAS. Results： MELAS has a wide heterogeneity in genetics and clinical manifestations. The relationship between mutations and phenotypes remains unclear. Advanced serial functional magnetic resonance imaging （MRI） can provide directional information on this disease. Muscle biopsy has meaningflil value in diagnosing MELAS, which shows the presence of ragged red fibers and mosaic appearance of cytochrome oxidase negative fibers. Genetic studies have reported that approximately 80% of MELAS cases are caused by the lnutation in.3243A〉G of the mitochondrial transfer RNA （Leu （UU R）） gene （MT-TLI）. Conclusions： MELAS involves multiple systems with variable clinical symptoms and recurrent episodes. The prognosis of MELAS patients depends on timely diagnosis. Therefore, overall diagnosis of MELAS should be based on the maternal inheritance family history, clinical manifestation, and findings from serial MR1, muscle biopsy, and genetics.