Abstract

Inborn Errors of Metabolism (IEMs) are a heterogeneous group of rare genetic disorders where deficiencies in enzymes, transporters, or cofactors disrupt metabolic pathways, leading to the toxic accumulation of substrates or vital endproduct deficiencies. Clinical conditions predominantly manifesting in children often masquerading as common neonatal ailments, where they present with extensive systemic manifestations, including acute encephalopathy, hepatomegaly, cardiomyopathy, and dysmorphic skeletal changes. Diagnosis of inborn errors includes basic emergency screening, specialised biochemical screening, advanced refined testing, and definitive genetic or functional confirmation. Management is divided into acute emergency stabilisation, focused on halting catabolism and removing toxins and chronic maintenance strategies, such as dietary substrate restriction, cofactor therapy, and advanced interventions like enzyme replacement therapy or organ transplantation. Optimal outcomes ultimately depend on the seamless collaboration of a multidisciplinary team and the empowerment of families to navigate the lifelong complexities of metabolic care.

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