Peculiarities of Expanded Newborn Screening for the Inherited Metabolic Disorders in Premature Newborns

Abstract

Occurrence of the premature birth in Ukraine is about 6%. Premature newborns are the highest risk group of developing chronic pathology of the nervous system, sensory organs, and respiratory system, causing neonatal mortality and disability; the latter is 22 times higher in premature newborns than in full-term ones. Besides, there is a large group of rare metabolic disorders that significantly disrupt the adaptation and nursing of newborns with signs of morpho-functional and enzymes immaturity. The efficacy of medical care of premature newborns to a great extent relates to prompt diagnosis as common somatic, as rare metabolic disorders.In view of the absence of specific symptoms, it is almost impossible to establish a diagnosis of inherited metabolic disordersduring the clinical examination of a neonate.Expanded newborn screening (ENBS) for inborn errors of metabolism (IEMs) proved to be an effective tool to single out newborns with genetic deficiency of certain metabolic enzymes.The practical experience of performingENBS indicates a problematic issue is the interpretation of results for preterm babies.This article is discussed the key factors affecting the predictive value of ENBS results in premature newborns, like peculiarities of blood sampling based on time intervals from delivery for certain nosologies, repeated sample taking for lab examination considering the basic principles of 2-nd Edition of CLSI "Guideline "Newborn Screening for Preterm, Low Birth Weight, and Sick Newborns, 2019". The CLSI Guideline presents the consensus solutions of a global team of neonatologists, metabolic paediatricians and medical geneticists regarding the accuracy, reliability and timing of laboratory determinations of IEM markers in the blood, as well as a set of factors to consider interpreting ENBS results for premature, low birth weight and newborns with perinatal pathology.The current procedure for neonatal screening for premature babies in Ukraine should be updated to modern requirements of the relevant clinical recommendations of world-recognized medical institutions, including CLSI. The critical issue in improving the quality and reliability of neonatal screening for preterm babies is multiple (repeated) blood sampling for laboratory determination of levels of biochemical IEM markers.A properly established and well- functioning system of expanded neonatal screening proved to be a highly effective tool for reducing early infant mortality and disability associated with inherited metabolic diseases.