# MELAS

> Página oficial: https://raras.org/doenca/melas
> Fonte: Raras.org — Banco de Dados de Doenças Raras em Português (CC BY-NC-SA 4.0)
> Última atualização: 2026-05-07

## Identificadores

- **ORPHA**: 550 — https://www.orpha.net/en/disease/detail/550
- **CID-10**: G71.3
- **OMIM**: OMIM:540000 — https://omim.org/entry/540000

## Descrição clínica

A síndrome MELAS (miopatia mitocondrial, encefalopatia, acidose láctica e acidente vascular cerebral) é uma doença multissistêmica progressiva rara caracterizada por encefalomiopatia, acidose láctica e episódios semelhantes a acidente vascular cerebral. Outras características incluem endocrinopatia, doenças cardíacas, diabetes, perda auditiva e manifestações neurológicas e psiquiátricas.

## Epidemiologia e herança

- **Prevalência**: Unknown
- **Padrão de herança**: Mitochondrial inheritance, Not applicable

## Sinais e sintomas (103 fenótipos HPO)

- **Cefaleia paroxística recorrente** — HPO: HP:0002331 (Frequente (79-30%))
- **Atraso no desenvolvimento da fala** — HPO: HP:0003828
- **HP:0001427** — HPO: HP:0001427
- **Miopatia mitocondrial** — HPO: HP:0003737
- **Hipertrofia do ventrículo esquerdo** — HPO: HP:0001712
- **Insuficiência cardíaca congestiva** — HPO: HP:0001635
- **Oftalmoplegia** — HPO: HP:0000602
- **Deficiência auditiva neurossensorial progressiva** — HPO: HP:0000408
- **Deficiência auditiva neurossensorial bilateral** — HPO: HP:0008619
- **Catarata do desenvolvimento** — HPO: HP:0000519
- **Anormalidade de crescimento** — HPO: HP:0001507
- **Hemianopsia** — HPO: HP:0012377
- **Hipertensão** — HPO: HP:0000822
- **Vômitos episódicos** — HPO: HP:0002572
- **Deficiência visual cerebral** — HPO: HP:0100704
- **Função ventricular esquerda anormal** — HPO: HP:0005162
- **Arritmia** — HPO: HP:0011675
- **Vômitos** — HPO: HP:0002013 (Frequente (79-30%))
- **Fraqueza muscular** — HPO: HP:0001324 (Muito frequente (99-80%))
- **Crise tônico-clônica bilateral** — HPO: HP:0002069 (Frequente (79-30%))
- **Diabetes mellitus** — HPO: HP:0000819 (Frequente (79-30%))
- **Hipoplasia do corpo caloso** — HPO: HP:0002079 (Ocasional (29-5%))
- **Mioclonias** — HPO: HP:0001336 (Frequente (79-30%))
- **Miopatia** — HPO: HP:0003198 (Frequente (79-30%))
- **Glomeruloesclerose segmentar focal** — HPO: HP:0000097 (Ocasional (29-5%))
- **Neuropatia axonal periférica** — HPO: HP:0003477 (Ocasional (29-5%))
- **Afasia** — HPO: HP:0002381 (Muito frequente (99-80%))
- **Psicose** — HPO: HP:0000709 (Frequente (79-30%))
- **Proteinúria** — HPO: HP:0000093 (Ocasional (29-5%))
- **Pseudo-obstrução intestinal** — HPO: HP:0004389 (Ocasional (29-5%))
- **Enxaqueca** — HPO: HP:0002076 (Muito frequente (99-80%))
- **Febre** — HPO: HP:0001945 (Ocasional (29-5%))
- **Constipação** — HPO: HP:0002019 (Ocasional (29-5%))
- **Mentação psicótica** — HPO: HP:0001345 (Ocasional (29-5%))
- **Transtorno afetivo bipolar** — HPO: HP:0007302 (Ocasional (29-5%))
- **Retinopatia pigmentar** — HPO: HP:0000580 (Ocasional (29-5%))
- **Pancreatite recorrente** — HPO: HP:0100027 (Ocasional (29-5%))
- **Aumento de lactato no LCR** — HPO: HP:0002490 (Frequente (79-30%))
- **Anemia** — HPO: HP:0001903 (Ocasional (29-5%))
- **Diarreia** — HPO: HP:0002014 (Ocasional (29-5%))
- _...e mais 63 sintomas. Ver https://raras.org/doenca/melas._

## Genes associados (19)

- **MT-TS2** [Candidate gene tested in]
- **MT-TL2** [MENDELIAN]
- **MT-TC** [MENDELIAN]
- **MT-TV** [MENDELIAN]
- **MT-CYB** — Cytochrome b [MENDELIAN]
  - Função: Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex) that is part of the mitochondrial respiratory chain. The b-c1 complex mediates electron transfer from
- **MT-TK** [MENDELIAN]
- **MT-ND1** — NADH-ubiquinone oxidoreductase chain 1 [Disease-causing germline mutation(s) in]
  - Função: Core subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I) which catalyzes electron transfer from NADH through the respiratory chain, using ubiquinone as an electron a
- **MT-ND6** — NADH-ubiquinone oxidoreductase chain 6 [Disease-causing germline mutation(s) in]
  - Função: Core subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I) which catalyzes electron transfer from NADH through the respiratory chain, using ubiquinone as an electron a
- **MT-TS1** [Disease-causing germline mutation(s) in]
- **MT-CO2** — Cytochrome c oxidase subunit 2 [Disease-causing germline mutation(s) in]
  - Função: Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes suc
- **MT-TF** [Disease-causing germline mutation(s) in]
- **MT-CO1** — Cytochrome c oxidase subunit 1 [Disease-causing germline mutation(s) in]
  - Função: Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes suc
- **MT-TH** [Candidate gene tested in]
- **MT-ND4** — NADH-ubiquinone oxidoreductase chain 4 [Disease-causing germline mutation(s) in]
  - Função: Core subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I) which catalyzes electron transfer from NADH through the respiratory chain, using ubiquinone as an electron a
- **MT-TL1** [Disease-causing germline mutation(s) in]

## Ensaios clínicos ativos (10)

- **NCT06792500** [RECRUITING]: A Basket Clinical Study to Assess Glycerol Tributyrate in Patients With Mitochondrial Encephalopathy, Lactic Acidosis, Stroke-like Episodes (MELAS) or Leber's Hereditary Optic Neuropathy-Plus (LHON-Plus) — https://clinicaltrials.gov/study/NCT06792500
- **NCT06451757** [RECRUITING]: KHENERFIN Study: A Trial to Evaluate the Efficacy and Safety of Sonlicromanol in Primary Mitochondrial Diseases — https://clinicaltrials.gov/study/NCT06451757
- **NCT01532791** [RECRUITING]: Natural History Study - Mitochondrial Disease — https://clinicaltrials.gov/study/NCT01532791
- **NCT06644534** [RECRUITING]: A Study to Assess TTI-0102 vs Placebo in MELAS Patients — https://clinicaltrials.gov/study/NCT06644534
- **NCT05554835** [RECRUITING]: Global Registry and Natural History Study for Mitochondrial Disorders — https://clinicaltrials.gov/study/NCT05554835
- **NCT06961344** [ENROLLING_BY_INVITATION]: An Open-label Extension Safety Study of MELAS Patients Who Completed TIS6463-203 (PRIZM) — https://clinicaltrials.gov/study/NCT06961344
- **NCT01803906** [ENROLLING_BY_INVITATION]: Tissue Sample Study for Mitochondrial Disorders — https://clinicaltrials.gov/study/NCT01803906
- **NCT06402123** [ACTIVE_NOT_RECRUITING]: A Phase 2b Study of Zagociguat in Patients With MELAS — https://clinicaltrials.gov/study/NCT06402123
- **NCT07429786** [NOT_YET_RECRUITING]: Evaluation of Efficacy and Tolerabilty of MelaB3 Serum in Combination of 35% Glycolic Acid Peeling Compared to 35% Glycolic Acid Peeling Alone in Various Hyperpigmentation Conditions — https://clinicaltrials.gov/study/NCT07429786
- **NCT06013397** [NOT_YET_RECRUITING]: Effectiveness of Ketogenic Diet in MELAS Syndrome — https://clinicaltrials.gov/study/NCT06013397

## Doenças relacionadas (por similaridade fenotípica)

- [Deficiência de coenzima Q10](https://raras.org/doenca/deficiencia-de-coenzima-q10) — ORPHA:35656 — 31 sintomas em comum
- [Neuro-hepatopatia de Navajo](https://raras.org/doenca/neuro-hepatopatia-de-navajo) — ORPHA:255229 — 31 sintomas em comum
- [Oftalmoplegia externa progressiva autossômica dominante](https://raras.org/doenca/oftalmoplegia-externa-progressiva-autossomica-dominante) — ORPHA:254892 — 28 sintomas em comum
- [Doença do metabolismo da tiamina](https://raras.org/doenca/doenca-do-metabolismo-da-tiamina) — ORPHA:298644 — 28 sintomas em comum
- [Epilepsia, mioclonia progressiva](https://raras.org/doenca/epilepsia-mioclonia-progressiva) — ORPHA:98261 — 28 sintomas em comum
- [Anemia sideroblástica](https://raras.org/doenca/anemia-sideroblastica) — ORPHA:1047 — 26 sintomas em comum
- [Deficiência de complexo III isolada](https://raras.org/doenca/deficiencia-de-complexo-iii-isolada) — ORPHA:1460 — 26 sintomas em comum
- [Deficiência isolada da ATP sintetase](https://raras.org/doenca/deficiencia-isolada-da-atp-sintetase) — ORPHA:254913 — 26 sintomas em comum
- [Encefalomiopatia neurogastrointestinal mitocondrial](https://raras.org/doenca/encefalomiopatia-neurogastrointestinal-mitocondrial) — ORPHA:298 — 26 sintomas em comum
- [Neuropatia óptica autossômica dominante](https://raras.org/doenca/neuropatia-optica-autossomica-dominante) — ORPHA:98672 — 26 sintomas em comum

## Importante

O Raras **não diagnostica e não prescreve**. Esta página é educativa e informativa.
Pacientes devem consultar profissionais de saúde qualificados para decisões clínicas.

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