AUTHOR=Lipiński Patryk , Wójcicka-Kowalczyk Katarzyna , Bogdańska Anna , Ehmke Ewa , Pajdowska Magdalena , Skrzypek Katarzyna , Charzewska Agnieszka , Hoffman-Zacharska Dorota TITLE=Case report: Early (molecular) diagnosis is the clue: report on ALDH7A1 deficiency in newborns JOURNAL=Frontiers in Genetics VOLUME=Volume 15 - 2024 YEAR=2024 URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2024.1464556 DOI=10.3389/fgene.2024.1464556 ISSN=1664-8021 ABSTRACT=The first-tier geneting testing for developmental and epileptic encephalopathies (DEE) is now increasingly used in routine clinical practice. Antiquitin deficiency, also referred to as pyridoxine-dependent epilepsy (PDE-ALDH7A1), represents an inherited metabolic disorder with the phenotype of an early-infantile DEE. Besides the fact that biochemical biomarkers of PDE-ALDH7A1, including α-aminoadipic semialdehyde dehydrogenase, pipecolic acid (PA), Δ1-piperideine-6-carboxylate, and 6-oxopipecolate (6-oxo-PIP) are well characterized, their analysis and usefulness have some limitations. Here we describe the case of a newborn presenting with seizures from the first hours of life, resistant to standard antiepileptic drugs, who was found to be a biallelic compound heterozygote of two clearly pathogenic variants in ALDH7A1 gene based on targeted next generation sequencing (NGS). The diagnostic process of PDE-ALDH7A1 was limited by the possibility to determine only urinary PA and 6-oxo-PIP (urinary organic acid profile using GC-MS method) and the exogenous peak of levetiracetam, due to the fact that it has a similar retention time as 6-oxo-PIP, masked the detection of 6-oxo-PIP.