[Analysis of screening results for genetic metabolic diseases among 352 449 newborns from Changsha].

OBJECTIVE: To retrospectively analyze the screening results for genetic metabolic diseases among newborns from Changsha in order to determine the prevalence of single diseases and their mutational spectrum. METHODS: 352 449 neonates born from January 2016 to December 2021 in Changsha were subjected to tandem mass spectrometry. Suspected cases were further analyzed by biochemical and genetic testing. RESULTS: Among the 352 449 newborns, 6 170 were positive for the screening, which yielded a positive rate of 1.75%. 5 437 cases were recalled, and 92 were confirmed, with the overall prevalence being 1∶3 831 and positive predictive value of 1.69%. Eighteen genetic metabolic diseases were detected among the 92 children, including 33 amino acid metabolic disorders, among which 20 were phenylalanine hydroxylase deficiency (60.60%). 17 cases had organic acid metabolic disorders, among which 4 were 2-methyl-dehydrogenase deficiency (23.50%). 42 had fatty acid metabolic disorders, among which 27 (64.30%) were primary carnitine deficiency and 12 were short-chain acyl-CoA dehydrogenase deficiency (28.60%). In total 90 genetic variants were identified, with the most common ones including c.51C>G, c.1400C>G, c.760C>T, c.1031A>G and c.1165A>G. CONCLUSION: The common neonatal genetic metabolic diseases in Changsha include primary carnitine deficiency, phenylalanine hydroxylase deficiency and short-chain acyl-CoA dehydrogenase deficiency. The preliminary delineation of mutational spectrum for genetic metabolic diseases in Changsha can facilitate early diagnosis and intervention, so as to improve the quality of newborn population.

Spectrum Analysis of Inherited Metabolic Disorders for Expanded Newborn Screening in a Central Chinese Population.

Neonatal inherited metabolic disorders (IMDs) are closely associated with early neonatal death and abnormal growth and development. Increasing attention has been paid to IMDs because of their high incidence and diversity. However, there are no reports about the incidence of IMDs in Changsha, China. Therefore, we retrospectively analyzed the screening results of neonates to evaluate the characteristics of IMDs in the area. From January 2016 to December 2020, 300,849 neonates were enrolled for expanded newborn screening by tandem mass spectrometry in the Neonatal Disease Screening Center of the Changsha Hospital for Maternal & Child Health Care. Newborns with mild initial results were recalled for repeated tests; if the second test was still positive, the patient was referred for confirmatory tests. A total of 71 confirmed cases were identified in our study, with an incidence rate of 1:4,237. There were 28 cases of amino acid metabolic disorders, representing 39.44% of the IMDs diagnosed, with an incidence rate of 1:10,745. Twelve newborns were diagnosed with organic acid metabolic disorders, accounting for 16.66% of IMDs, with an incidence rate of 1:25,071. There were 31 cases of fatty acid oxidation disorders, representing 43.05% of IMDs, with an incidence rate of 1:9,705. Overall, 14 types of IMDs were found in Changsha. The most common disorders in the region were primary carnitine deficiency, hyperphenylalaninemia and short-chain acyl-CoA dehydrogenase deficiency. Their incidence rate is respectively 1:13,675, 1:16,714 and 1:42,978. The mutations in PAH, SLC22A5, and ACADS are the leading causes of IMDs in this area. This study demonstrates the importance of utilizing MS/MS in IMD screening for early diagnosis and treatment. This strategy may be used for prenatal genetic counseling to avoid irreversible growth and intellectual development disorders in children.

[Neurobehavioral development in preterm infants: a retrospective study of 181 cases].

OBJECTIVE: To investigate the results of Gesell Developmental Scale in follow-up of preterm infants and to determine possible high-risk factors for poor long-term neurological outcome. METHODS: A preterm infants' questionnaire was designed, and a retrospective study was conducted on the clinical data of 181 preterm infants (corrected age 2-12 months) and their mothers. The developmental quotient (DQ) scores were determined by the Gesell Developmental Scale and statistically analyzed. RESULTS: Compared with those with a birth weight (BW) of ≥1 500 g, the preterm infants with a BW of <1 500 g had significantly reduced DQ scores of adaptability, gross motor movement, and fine movement (P<0.05). Compared with those with a gestational age (GA) of ≥32 weeks, the preterm infants with a GA of <32 weeks had significantly reduced DQ scores of adaptability, gross motor movement, fine movement, and social contact (P<0.05). DQ scores on five Gesell subscales were significantly positively correlated with GA and BW (P<0.05). The DQ scores on Gesell subscales showed a significant negative correlation with severe complications in neonatal period (P<0.001). CONCLUSIONS: For preterm infants, BW <1 500 g and GA <32 weeks are high-risk factors for abnormal adaptability, gross motor movement, fine movement, and social contact, and this group of infants should be followed up closely. Severe complications in neonatal period may be associated with poor long-term neurological outcome and should be effectively prevented and treated.