MELAS
Synonymes : Encéphalomyopathie mitochondriale, acidose lactique, pseudo-épisodes vasculaires cérébraux · Encéphalopathie mitochondriale, acidose lactique, pseudo-épisodes vasculaires cérébraux · Myopathie mitochondriale, encéphalopathie, acidose lactique, pseudo-épisodes vasculaires cérébraux
Définition clinique
Maladie neurométabolique rare d'origine génétique, progressive et multisystémique en raison d'un dysfonctionnement mitochondrial, caractérisée par une encéphalomyopathie, une acidose lactique et des épisodes mimant un accident vasculaire cérébral.
🩺 Symptômes & manifestations cliniques
87 phénotypes HPO annotés Orphanet
🔴 Très fréquent (99-80%) — 13
- Dementia
- Seizure
- Muscle weakness
- Migraine
- Increased circulating lactate concentration
- EEG abnormality
- Aphasia
- Stroke-like episode
- Lactic acidosis
- Ragged-red muscle fibers
- Abnormal mitochondria in muscle tissue
- Aplasia/Hypoplasia of the cerebral white matter
- Widened cerebral subarachnoid space
🟠 Fréquent (79-30%) — 26
- Sensorineural hearing impairment
- Visual loss
- Psychosis
- Depression
- Short attention span
- Anxiety
- Diabetes mellitus
- Ataxia
- Hemiparesis
- Gait disturbance
- Encephalopathy
- Specific learning disability
- Myoclonus
- Vomiting
- Bilateral tonic-clonic seizure
- Basal ganglia calcification
- Recurrent paroxysmal headache
- Memory impairment
- Increased CSF lactate
- Increased CSF protein concentration
- Myopathy
- Short stature
- Fluctuations in consciousness
- Focal-onset seizure
- Peripheral neuropathy
- Impaired visuospatial constructive cognition
🟡 Occasionnel / autres (48) ↓
- Distal peripheral sensory neuropathy(Occasionel (29-5%))
- Sensorimotor neuropathy(Occasionel (29-5%))
- Bipolar affective disorder(Occasionel (29-5%))
- Mixed demyelinating and axonal polyneuropathy(Occasionel (29-5%))
- Erythema(Occasionel (29-5%))
- Abnormality of central motor function(Occasionel (29-5%))
- Brain atrophy(Occasionel (29-5%))
- Elevated brain lactate level by MRS(Occasionel (29-5%))
- Stuttering(Occasionel (29-5%))
- Cardiac conduction abnormality(Occasionel (29-5%))
- Recurrent pancreatitis(Occasionel (29-5%))
- Type I diabetes mellitus(Occasionel (29-5%))
- Hypogonadotropic hypogonadism(Très rare (4-1%))
- Hypothyroidism(Très rare (4-1%))
- Hypoparathyroidism(Très rare (4-1%))
- Proteinuria(Occasionel (29-5%))
- Focal segmental glomerulosclerosis(Occasionel (29-5%))
- Nephropathy(Occasionel (29-5%))
- Proximal tubulopathy(Occasionel (29-5%))
- Pigmentary retinopathy(Occasionel (29-5%))
- Progressive external ophthalmoplegia(Occasionel (29-5%))
- Optic atrophy(Occasionel (29-5%))
- Personality changes(Occasionel (29-5%))
- Hypertrichosis(Occasionel (29-5%))
- Vitiligo(Occasionel (29-5%))
- Global developmental delay(Occasionel (29-5%))
- Motor delay(Occasionel (29-5%))
- Agenesis of corpus callosum(Occasionel (29-5%))
- Psychotic mentation(Occasionel (29-5%))
- Failure to thrive(Occasionel (29-5%))
- Cardiomyopathy(Occasionel (29-5%))
- Hypertrophic cardiomyopathy(Occasionel (29-5%))
- Dilated cardiomyopathy(Occasionel (29-5%))
- Wolff-Parkinson-White syndrome(Occasionel (29-5%))
- Anemia(Occasionel (29-5%))
- Fever(Occasionel (29-5%))
- Diarrhea(Occasionel (29-5%))
- Constipation(Occasionel (29-5%))
- Hypoplasia of the corpus callosum(Occasionel (29-5%))
- Pulmonary arterial hypertension(Occasionel (29-5%))
- Cerebral cortical atrophy(Occasionel (29-5%))
- Gastrointestinal dysmotility(Occasionel (29-5%))
- Peripheral axonal neuropathy(Occasionel (29-5%))
- Exercise intolerance(Occasionel (29-5%))
- Reduced consciousness(Occasionel (29-5%))
- Intestinal pseudo-obstruction(Occasionel (29-5%))
- Concentric hypertrophic cardiomyopathy(Occasionel (29-5%))
- Type II diabetes mellitus(Occasionel (29-5%))
🔀 Diagnostic différentiel
Maladies rares qui partagent le plus de phénotypes discriminants avec MELAS. Calcul automatique sur les annotations HPO/Orphanet — à confronter au tableau clinique réel.
- 38%
Syndrome de Sneddon
ORPHA:820 · 5/8 phénotypes en commun
- 44%
Acidose lactique congénitale type Saguenay-Lac-Saint-Jean
ORPHA:70472 · 4/8 phénotypes en commun
- 41%
Acidurie 3-méthylglutaconique type 9
ORPHA:505216 · 4/8 phénotypes en commun
- 38%
Maladie de Creutzfeldt-Jakob héréditaire
ORPHA:282166 · 4/8 phénotypes en commun
- 38%
Syndrome de Flynn-Aird
ORPHA:2047 · 4/8 phénotypes en commun
- 38%
Maladie d'Alexander
ORPHA:58 · 4/8 phénotypes en commun
📚 Publications récentes (2 dernières années)
12 références PubMed — guidelines, revues, méta-analyses et case reports avec « MELAS » dans le titre/abstract.
- Review
Riboflavin therapy in complex I deficiency: Two new cases of leukoencephalopathy and a systematic literature review
Ferrera G et al. · J Neurol Sci · 2026 · PMID 42476091
- Review
Fish Poxviruses on the Rise: Prospects for Aquatic Health
Adamek M et al. · J Fish Dis · 2026 · PMID 42103699
- Review
COQ8A-related Primary Coenzyme Q10 Deficiency Mimicking Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like Syndrome: A Pediatric Case Report and Review of Mitochondrial Mimics
Reddy SB et al. · Ann Afr Med · 2026 · PMID 41992454
- Review
Hyperinflammatory syndromes in primary mitochondrial disease: A three-center case series and focused review
Brooks DR et al. · Mol Genet Metab · 2026 · PMID 42828919
- Review
Immunopathogenesis of Immune Checkpoint Inhibitor-Induced Myositis, Myocarditis and Myasthenia Gravis Overlap Syndrome: A Mechanistic Synthesis of a Mitochondrial Autoantigen Hypothesis
Ismail U · Cureus · 2026 · PMID 42707790
- Review
Endothelial-mitochondrial coupling in mitochondrial disease: A systematic review and quantitative synthesis of vascular, biochemical, and oxidative bioenergetic dysfunction
Adams JA et al. · Ther Adv Rare Dis · 2026 · PMID 42707614
- Review
Mitochondrial DNA A3243G variant-associated MELAS: Recent advances in clinical trials, therapeutic interventions, and disease-modifying strategies
Chu KY · Intractable Rare Dis Res · 2026 · PMID 42644018
- Case
Navigating Heart Failure and Atrial Fibrillation Therapy in MELAS
Kwon H et al. · JACC Case Rep · 2026 · PMID 42820902
🔬 Examens & investigations
📋 PNDS — recommandations officielles françaises
Le Protocole National de Diagnostic et Soins est le référentiel HAS pour la prise en charge d'une maladie rare en France. Environ 300 maladies en disposent (plus rare que la maladie elle-même → plus de chances qu'il n'existe pas).
🏥 Centres experts
Liste Orphanet officielle des centres experts pour cette maladie spécifique (CRMR / CCMR) — coordonnées et coordinateurs.
📍 Trouver un spécialiste près de chez vous
Entrez votre ville ou code postal pour filtrer l'annuaire MonRhumato et localiser les centres experts les plus proches.
🧬 Gènes associés & variants
MT-CO1mitochondriaDisease-causing germline mutation(s) inAssessed
MT-CO2mitochondriaClinVar : 139 variantsDisease-causing germline mutation(s) inAssessed
MT-CO3mitochondriaCandidate gene tested inNot yet assessed
MT-ND1mitochondriaDisease-causing germline mutation(s) inAssessed
MT-ND4mitochondriaDisease-causing germline mutation(s) inAssessed
MT-ND5mitochondriaDisease-causing germline mutation(s) inAssessed
MT-ND6mitochondriaDisease-causing germline mutation(s) inAssessed
MT-TL1mitochondriaDisease-causing germline mutation(s) inAssessed
MT-TQmitochondriaCandidate gene tested inNot yet assessed
MT-TWmitochondriaDisease-causing germline mutation(s) inAssessed
MT-THmitochondriaCandidate gene tested inNot yet assessed
MT-TS1mitochondriaDisease-causing germline mutation(s) inAssessed
MT-TS2mitochondriaCandidate gene tested inNot yet assessed
MT-TFmitochondriaDisease-causing germline mutation(s) inAssessed
Codifications validées (8) ↓
- GARD:7009
- ICD-10:G71.3
- ICD-11:8C73.Y
- MONDO:0010789
- MeSH:D017241
- MedDRA:10053872
- OMIM:540000
- UMLS:C0162671