# Diagnosing Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-Like Episodes (MELAS) Syndrome in a Young Adult Female Patient With Seizures and Lactic Acidosis

## TL;DR

This case report describes the diagnosis and treatment of a rare mitochondrial disorder, MELAS syndrome, in a young woman with seizures and lactic acidosis.

## Contribution

The paper presents a rare case of MELAS syndrome in a young adult, emphasizing diagnostic challenges and the importance of early recognition.

## Key findings

- The patient's symptoms and muscle biopsy confirmed mitochondrial cytopathy consistent with MELAS syndrome.
- Supportive therapy and a mitochondrial cocktail led to gradual clinical improvement.
- The case highlights the need to consider MELAS in the differential diagnosis of stroke-like episodes in young patients.

## Abstract

The aim of this case report is to highlight the diagnostic challenges and clinical presentation of mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome, which is a rare, maternally inherited mitochondrial disorder. MELAS typically manifests with a constellation of neurological and systemic symptoms, including seizures, lactic acidosis, stroke-like episodes, and progressive cognitive decline. Mutations in mitochondrial DNA impair oxidative phosphorylation and result in widespread cellular dysfunction.

We report the case of a 33-year-old female patient who presented with seizures, altered mental status, and focal neurological deficits. Laboratory evaluation revealed elevated serum lactate, and neuroimaging demonstrated stroke-like lesions not confined to vascular territories. A muscle biopsy showed abnormal mitochondrial accumulation, and electron microscopy detected ragged red fibers, which is confirmatory of mitochondrial cytopathy. The patient was managed symptomatically in the intensive care unit with antiepileptics, corticosteroids, and a mitochondrial cocktail comprising coenzyme Q10, L-arginine, L-carnitine, and B-complex vitamins. Plasmapheresis was also performed during initial management due to diagnostic uncertainty. The patient showed gradual clinical improvement and was discharged on supportive therapy.

This case emphasizes the importance of early recognition of atypical stroke-like presentations and metabolic derangements in young patients. MELAS syndrome should be considered in the differential diagnosis of stroke mimics, especially in the absence of vascular risk factors. Timely diagnosis, supportive care, and long-term follow-up, including genetic counselling, are essential for optimizing outcomes in these patients.