This work is licensed under Creative Commons Attribution 4.0 License Page 1 Published By ICON Publishers Research Article The epidemiology of inborn metabolic errors and challenges in Nigeria Obasi Miriam O 1 , Iwuamadi Ojiugo 1 , Onyeka Okafor 1 , Alozie Okezie 1 , Oparaocha Divine Gift 1 and *Johnkennedy Nnodim 1 1 Department of Medical Laboratory Science, Imo State University, Owerri, Imo State, Nigeria. Introduction Reducing child mortality is still a major worldwide concern [1]. It is a measure of both the general social and economic development of a country and the well-being of its children [2]. Child survival rates continue to confront major obstacles even after the Millennium Development Goals (MDGs) were developed and put into practice. A total of 5.491 million child deaths occurred during the aforementioned period, of which 2.681 million occurred during the neonatal period, accounting for 45.1% of the total child mortality under five years of age [4], despite a 53% decrease in the mortality rate for children under five years of age [3]. According to data from the World Health Organization (WHO), the sub-Saharan African region accounts for seventy-four fatalities for every 1000 live births. There is significant disparity in child survival rates, as the rate is over fourteen times greater than those reported in North America and Europe. Sub-Saharan Africa and Southern Asia accounted for over 80% of the 5 million children under five who died worldwide in 2020. Notably, Nigeria, India, Pakistan, the Democratic Republic of the Congo, and Ethiopia accounted for half of these fatalities [5]. One of the major problems in pediatric populations is biochemical genetics, specifically Inborn Errors of Metabolisms (IEMs). A broad category of uncommon illnesses known as Inborn Errors of Metabolisms (IEMs) are caused by a single enzyme's inadequate performance within a metabolic pathway. These conditions frequently result from genetic changes that change the structure or activity of enzymes, which affects the body's capacity to carry out particular biochemical activities necessary for regular physiological function [6], [7]. One of the factors causing 5.1% of neonatal deaths and 3.5% of fatalities in children ages 1 to 59 months is congenital abnormalities [8]. According to the research that is currently ICON Journal of Applied Medical Sciences Volume 01 | Issue 02 | 2025 Journal homepage: https://iconpublishers.com/icon-j-app-med-sci/ DOI: 10.5281/zenodo.17174252 Corresponding author: Johnkennedy Nnodim Department of Medical Laboratory Science, Imo State University, Owerri, Imo State, Nigeria. Received Date : 10 Aug. 2025 Published Date: 22 Sept. 2025 Abstract Inborn errors of metabolism are a class of genetically based illnesses that are uncommon on their own but can be extremely serious when combined. The body is unable to convert food into energy correctly in this set of uncommon genetic (inherited) illnesses. Poor outcomes during pregnancy and infancy are linked to congenital birth abnormalities. In developed nations, next generation sequencing (NGS) and tandem mass spectrometry (MS/MS) are used to investigate inborn errors of metabolism. In developing nations, such as Nigeria, these disorders are rarely screened for because of a lack of resources and public and healthcare professional awareness. Because Nigeria has few or no screening programs in place, there is a lack of epidemiological data on inborn metabolic faults throughout the country's six geopolitical zones, which this research aims to fill. Lack of countrywide newborn screening, insufficient diagnostic facilities, and low healthcare provider awareness are some of the obstacles to the screening and detection of inborn metabolic abnormalities in Nigeria. However, there is evidence of inborn errors of metabolism in Nigeria, as evidenced by the case of a 14-month-old boy with Glycogen Storage Disease Type 111a. This highlights the need for significant clinical awareness of inborn errors of metabolism. Keywords: Inborn errors, metabolism, Glycogen Storage Disease, congenital, birth defects.