Analysis of clinical features, biochemical indices and genetic variants among children with Short/branched-chain acyl-CoA dehydrogenase deficiency detected by neonatal screening.
10.3760/cma.j.cn511376-20220318-00179
- Author:
HanYi ZHAO
1
;
Duo ZHOU
;
Haixia MIAO
;
Chi CHEN
;
Jianbin YANG
;
Rulai YANG
;
Xinwen HUANG
Author Information
1. Department of Genetics and Metabolism, Children's Hospital Affiliated to Zhejiang University School of Medicine, National Clinical Research Center for Child Health, National Children's Regional Medical Center, Hangzhou, Zhejiang 310052, China. 6305022@zju.edu.cn.
- Publication Type:Journal Article
- MeSH:
Humans;
Infant, Newborn;
Amino Acid Metabolism, Inborn Errors/genetics*;
Carnitine;
Neonatal Screening/methods*
- From:
Chinese Journal of Medical Genetics
2023;40(2):155-160
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To investigate the clinical manifestations, biochemical abnormalities and pathogenic variants among children with Short/branched-chain acyl-CoA dehydrogenase (SBCAD) deficiency detected by neonatal screening.
METHODS:A total of 2 730 852 newborns were screened from January 2016 to December 2021 with liquid chromatography tandem mass spectrometry. Suspected SBCAD deficiency patients were diagnosed by urine organic acid analysis and high-throughput gene sequencing analysis. The clinical, biochemical and genetic changes of the confirmed cases were analyzed, in addition with guidance for diet and life management, L-carnitine supplement, and survey of growth and intellectual development.
RESULTS:Twelve cases of SBCAD deficiency were diagnosed, which yielded a prevalence of 1/227 571. The lsovaleryl carnitine (C5) of primary screening blood samples was between 0.6 and 2.1 µmol/L, all exceeded the normal range. C5/acety1 carnitine (C2) was between 0.02 and 0.12, with 6 cases exceeding the normal range. C5/propionyl carnitine (C3) was between 0.1 and 1.16, with 5 cases exceeding the normal range. Free carnitine (C0) was between 18.89 and 58.12 µmol, with 1 case exceeding the normal range. Three neonates with abnormal screening results were recommended to have appropriate restriction for protein intake and two were given L-carnitine. During follow-up, their C5 has ranged from 0.22 to 2.32 µmol/L, C5/C2 has ranged from 0.01 to 0.31, C5/C3 has ranged from 0.14 to 1.7. C5 or C5/C2 and C5/C3 were transiently normal in all patients except for case 8 during the neonatal screening and follow-up. C0 was 17.42 ∼ 76.83 µmol/L Urine organic acid analysis was carried out in 9 of the 12 cases, and 2-methylbutyroglycine was elevated in 8 cases. Urine organic acid analysis was carried out in 9 cases, and 2-methylbutyrylglycine was increased in 8 cases. Genetic analysis was carried out for 11 children, and in total 6 ACADSB gene variants were identified, which included 4 missense variants (c.655G>A, c.923G>A, c.461G>A, c.1165A>G), 1 frameshift variant (c.746del) and 1 nonsense variant (c.275C>G). Among these, the C.461G>A variant was unreported previously. The most common variants were c.1165A>G (40.9%) and C.275C>G (22.7%). The patients were followed up for 18 days to 55 months. Only one patient had mental retardation, with the remainders having normal physical and mental development.
CONCLUSION:SBCAD deficiency is a rare disease. The detection rate of newborn screening in this study was 1/227 571. Early intervention can be attained in most asymptomatic patients through neonatal screening. In this study, the common gene variants are c.1165A>G and c.275C>G.
