Inherited metabolic disorders in a cohort of Egyptian children

Abstract Background Inborn errors of metabolism (IEMs) represent a special challenge in pediatric practice. Despite the unquestionable clinical significance of newborn screening, it just offers a snapshot of an extremely minor subgroup of metabolic disorders. So, it is crucial to use multiple techniques for accurate diagnosis of a wider spectrum of IEMs early in infancy to prevent overwhelming irreversible neurological complications in a cohort of high-risk Egyptian pediatrics. This study included four thousand and eighty suspected IEMs patients. They were referred to the Chromatography Unit, Clinical Biochemistry and Molecular Diagnostics Laboratories, National Liver Institute (NLI) for laboratory assessment in the period from March 2016 to November 2020. Separation of amino acids and acylcarnitines using tandem mass spectrometry (LC/MS) and organic acids using gas chromatography mass spectrometry (GC/MS) was done. Results Three hundred and twenty (320/4080, 7.8%) patients were diagnosed with IEMs. The following disorders were identified: organic acidopathies—200 (62.5%) including methylmalonic acidemia (MMA) (48/320, 15%), glutaric academia (GA) (40/320, 12, 5%), propionic acidemia (PA), (32/320, 10%), isovaleric acidemia (IVA) (40/320, 12.5%), methylcrotonyl glyceinuria (16/320, 5%), and orotic acidemia (24/320, 7.5%); amino acidopathies—80 (25%) including maple syrup urine disease (MSUD) (32/320, 10%), phenylketonuria (24/320, 7.5%), homocystinuria (16/320, 5%), and nonketotic hyperglycinemia (8/320, 2.5%) in addition to fatty acid disorders (FAO): 24 (7.5%) and lactic academia (LA), 16 (5%). Conclusion Early detection of IEMs by rapid non-invasive techniques. LC/MS and GC/MS. is a crucial process for early diagnosis of different types of IEMs to install therapeutic clue in a group of high-risk Egyptian pediatrics for proper treatment and better outcome