Congenital Pediatric Dementia: a Case Study of Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like Episodes (MELAS) Syndrome

Abstract

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial genetic condition affecting the capacity of the cells to create energy. Tissues with high-energy demands, such as the brain tissue, are disproportionately affected by this disease and result in significant neurological sequela including seizures and stroke-like episodes. The cognitive and behavioral impact of these neurological insults is evident in neuropsychological impairments that are initially transient but eventually become permanent and ultimately lead to dementia and death. The age of onset for MELAS is between 5 and 15 years old and is preceded by a period of typical development. The disease course of MELAS in combination with its onset in childhood and adolescence poses a number of challenges to pediatric neuropsychologists, who are often charged with quantifying impairment over time and communicating to a broad audience the appropriate services and supports that the individual needs. This case study aims to provide pediatric neuropsychologists with an overview of MELAS and offers an approach to neuropsychological assessments among children and adolescents with disorders with a dementing disease course. The affected individual, a 19-year-old woman, presented for an initial neuropsychological evaluation following a protracted period of seizures; the etiology of which had only recently been identified as a symptom of MELAS. Considerations for tracking progress and decline longitudinally and recommendations addressing the mental health and educational needs of these individuals are addressed.