{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T17:12:42Z","timestamp":1783789962521,"version":"3.55.0"},"reference-count":60,"publisher":"FapUNIFESP (SciELO)","issue":"11","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Arq. Neuro-Psiquiatr."],"published-print":{"date-parts":[[2015,11]]},"abstract":"<jats:p>ABSTRACTMitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes (MELAS) is a rare mitochondrial disorder. Diagnostic criteria for MELAS include typical manifestations of the disease: stroke-like episodes, encephalopathy, evidence of mitochondrial dysfunction (laboratorial or histological) and known mitochondrial DNA gene mutations. Clinical features of MELAS are not necessarily uniform in the early stages of the disease, and correlations between clinical manifestations and physiopathology have not been fully elucidated. It is estimated that point mutations in the tRNALeu(UUR) gene of the DNAmt, mainly A3243G, are responsible for more of 80% of MELAS cases. Morphological changes seen upon muscle biopsy in MELAS include a substantive proportion of ragged red fibers (RRF) and the presence of vessels with a strong reaction for succinate dehydrogenase. In this review, we discuss mainly diagnostic criterion, clinical and laboratory manifestations, brain images, histology and molecular findings as well as some differential diagnoses and current treatments.<\/jats:p>","DOI":"10.1590\/0004-282x20150154","type":"journal-article","created":{"date-parts":[[2015,10,24]],"date-time":"2015-10-24T17:22:39Z","timestamp":1445707359000},"page":"959-967","source":"Crossref","is-referenced-by-count":56,"title":["When should MELAS (Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes) be the diagnosis?"],"prefix":"10.1590","volume":"73","author":[{"given":"Paulo Jos\u00e9","family":"Lorenzoni","sequence":"first","affiliation":[{"name":"Universidade Federal do Paran\u00e1,  Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lineu Cesar","family":"Werneck","sequence":"additional","affiliation":[{"name":"Universidade Federal do Paran\u00e1,  Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cl\u00e1udia Suemi Kamoi","family":"Kay","sequence":"additional","affiliation":[{"name":"Universidade Federal do Paran\u00e1,  Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos Eduardo Soares","family":"Silvado","sequence":"additional","affiliation":[{"name":"Universidade Federal do Paran\u00e1,  Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosana Herminia","family":"Scola","sequence":"additional","affiliation":[{"name":"Universidade Federal do Paran\u00e1,  Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"530","reference":[{"key":"ref1","author":"Koenigsberger MR","year":"1976"},{"issue":"7","key":"ref2","doi-asserted-by":"crossref","first-page":"614","DOI":"10.1212\/WNL.25.7.614","article-title":"Familial poliodystrophy, mitochondrial myopathy, and lactate acidemia","volume":"25","author":"Shapira Y","year":"1975","journal-title":"Neurology"},{"issue":"4","key":"ref3","doi-asserted-by":"crossref","first-page":"481","DOI":"10.1002\/ana.410160409","article-title":"Mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes: a distinctive clinical syndrome","volume":"16","author":"Pavlakis SG","year":"1984","journal-title":"Ann Neurol"},{"issue":"3","key":"ref4","doi-asserted-by":"crossref","first-page":"288","DOI":"10.1590\/S0004-282X1987000300009","article-title":"MELAS (mitochondrial encephalopathy, lactic acidosis and stroke like episodes): case report","volume":"45","author":"Werneck LC","year":"1987","journal-title":"Arq Neuropsiquiatr"},{"issue":"2","key":"ref5","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/0960-8966(92)90045-8","article-title":"Melas: an original case and clinical criteria for diagnosis","volume":"2","author":"Hirano M","year":"1992","journal-title":"Neuromuscul Disord"},{"issue":"5","key":"ref6","doi-asserted-by":"crossref","first-page":"619","DOI":"10.1016\/j.bbagen.2011.03.015","article-title":"MELAS: a nationwide prospective cohort study of 96 patients in Japan","volume":"1820","author":"Yatsuga S","year":"2012","journal-title":"Biochim Biophys Acta"},{"key":"ref7","doi-asserted-by":"crossref","first-page":"S107","DOI":"10.1002\/mus.880181422","article-title":"Clinical features of MELAS and mitochondrial DNA mutations","volume":"18","author":"Goto Y","year":"1995","journal-title":"Muscle Nerve"},{"issue":"4","key":"ref8","doi-asserted-by":"crossref","first-page":"449","DOI":"10.1007\/BF00713541","article-title":"Central nervous system changes in mitochondrial encephalomyopathy: light and electron microscopic study","volume":"83","author":"Mizukami K","year":"1992","journal-title":"Acta Neuropathol"},{"issue":"3","key":"ref9","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1007\/BF00688185","article-title":"Mitochondrial angiopathy in cerebral blood vessels of mitochondrial encephalomyopathy","volume":"74","author":"Ohama E","year":"1987","journal-title":"Acta Neuropathol"},{"issue":"6","key":"ref10","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1002\/ana.410250611","article-title":"Vascular involvement in mitochondrial myopathy","volume":"25","author":"Sakuta R","year":"1989","journal-title":"Ann Neurol"},{"issue":"8","key":"ref11","doi-asserted-by":"crossref","first-page":"1420","DOI":"10.1161\/01.STR.27.8.1420","article-title":"Adult-onset MELAS. 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