Mitochondrial Dysfunction in an Adolescent with Mental Health Problems: A Case Report

We report the case of a 13 year old boy with autism spectrum disorder (ASD), moderate intellectual disability, and severe conduct disorder in whom clinical and paraclinical findings suggested mitochondrial dysfunction. Neurodevelopmental assessment showed a WISC V Full Scale IQ of 55 and ADI R scores above diagnostic cut offs. Laboratory tests revealed fluctuating hyperlactatemia (up to 3.56 mmol/L) and a cerebrospinal fluid lactate/pyruvate ratio of 72 (lactate 1.80 mmol/L; pyruvate 0.025 mmol/L), highly suggestive of a respiratory chain defect. Brain MRI demonstrated bilateral, symmetric T2/FLAIR hyperintensities of the corticospinal tracts. No alternative metabolic or genetic abnormalities were identified (normal amino acid profile, normal karyotype). A mitochondrial “cocktail” (coenzyme Q10, riboflavin, L carnitine, alpha lipoic acid) was initiated alongside multidisciplinary psychosocial management. This case underscores the importance of targeted metabolic evaluation in atypical or severe neuropsychiatric presentations, as early identification of mitochondrial involvement may inform tailored therapeutic strategies and improve outcomes.