Abstract
Myoclonic epilepsy with ragged red fibers (MERRF) syndrome is a primary mitochondrial disorder characterized by myoclonus, epilepsy, ataxia, and muscle fiber abnormalities. While traditionally associated with neurological features, MERRF's multisystem nature extends to endocrine dysfunction, including diabetes mellitus, thyroid disorders, and adrenal abnormalities. This case report explores the multifaceted nature of MERRF syndrome by presenting the clinical journey of a 70-year-old woman who sought care at the endocrinology clinic due to coexisting Addison's disease and diabetes mellitus, marked by recurrent hypoglycemia and suboptimal metabolic control. Over time, she developed a history of myoclonic epilepsy, effectively managed with lamotrigine, along with mild sensory axonal polyneuropathy and ataxia. The patient was diagnosed with MERRF syndrome following her son's diagnosis, which had a severe form. This case underscores the intricate interplay between mitochondrial dysfunction and endocrine manifestations in MERRF syndrome, highlighting the importance of a comprehensive and multidisciplinary approach to patient care. MERRF syndrome's array of endocrine manifestations substantially impacts patients' quality of life and morbidity. A comprehensive approach, uniting endocrinologists, neurologists, geneticists, and other specialists, is essential for effective patient care. Further research is warranted to unravel the complex mitochondrial-endocrine interactions in MERRF syndrome, offering potential insights for improved management.