Case ReportsNeedle EMG, a Jigsaw to Disclose Lipid Storage Myopathy Due to Multiple Acyl-CoA Dehydrogenase DeficiencySantananukarn, Manasawan MD; Amornvit, Jakkrit MD; Pasutharnchat, Nath MD; Jongpiputvanich, Sungkom MDAuthor Information From the Division of Neurology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand (MS, JA, NP); King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand (MS, JA, NP, SJ); and Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand (SJ). All correspondence should be addressed to: Nath Pasutharnchat, MD, Division of Neurology, Bhumisiri Building, Floor 7 Zone C, King Chulalongkorn Memorial Hospital, Bangkok, Thailand 10330. This study was presented at the 17th Asian and Oceanian Myology Center Meeting (AOMC), July 27–29, 2018, Kuala Lumpur, Malaysia. Manasawan Santananukarn is in training. Financial disclosure statements have been obtained, and no conflicts of interest have been reported by the authors or by any individuals in control of the content of this article. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.ajpmr.com). Online date: June 20, 2019 American Journal of Physical Medicine & Rehabilitation: June 2020 - Volume 99 - Issue 6 - p e71-e74 doi: 10.1097/PHM.0000000000001230 Buy SDC Metrics Abstract Multiple acyl-CoA dehydrogenase deficiency is a rare autosomal recessive inborn error of metabolism. The late-onset multiple acyl-CoA dehydrogenase deficiency is frequently caused by mutations in ETFDH gene. Because of its clinical heterogeneity, diagnosis and treatment of late-onset multiple acyl-CoA dehydrogenase deficiency are often delayed. The authors described a previously healthy 40-yr-old Thai woman presenting with subacute severe weakness of bulbar-limb muscles and elevated serum creatine kinase. The authors emphasized the importance of needle EMG and prompt muscle histopathological evaluation, which rapidly led to the diagnosis and riboflavin therapy, resulting in a dramatic and rapid improvement before genetic study disclosed mutation in ETFDH gene. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.