Prevalence and outcome of inborn errors of metabolism among high-risk neonates: an Egyptian single-center study

Abstract

Background Inborn errors of metabolism (IEM) are genetic disorders caused by incompetence in enzymatic reactions of intermediary metabolism due to an insufficient amount or unstable form of the involved enzyme. Aim To assess the prevalence and outcome of IEM among high-risk neonates for early diagnosis and detection of treatable causes to minimize morbidity and mortality rate in neonates. Methods This cross-sectional study was carried out on 684 neonates at the Neonatal Intensive Care Unit in the Pediatrics Department at Zagazig University Children’s Hospital from February 2020 to February 2023. Extended metabolic screen (EMS) was done for full-term neonates and preterm of more than 32 weeks of gestation. Further investigations such as plasma ammonia, plasma lactate, urine organic acid analysis, blood gas, serum anion gap, and the blood glucose level were also measured. Results The prevalence of IEM was 4.4%. The most common presentations among the cases of IEM were not doing well, respiratory distress, encephalopathy, and convulsion. As regards provisional diagnosis, 11 cases were diagnosed as maple syrup urine disease, 5 cases with glycine encephalopathy, 5 cases with medium-chain acyl CoA dehydrogenase deficiency,4 cases with methylmalonic acidemia, 2 cases with isovaleric acidemia, 2 cases with citrullinemia type 1, and one case with propionic academia; 12 (40%) of IEM cases died. Conclusion IEM disorders are not rare diseases in high-risk neonates with attention to consanguinity, which is a common tradition in our country. The delay in diagnosis of IEM leads to high morbidity and mortality.