Application value of tandem mass spectrometry combined with gas phase mass spectrometry in screening and diagnosis of inherited metabolic diseases in neonatal intensive care unit
Objective To investigate the application value of tandem mass spectrometry(MS/MS)combined with gas phase mass spectrometry(GC-MS)in screening and diagnosis of inherited metabolic disorders(IMD)in neonatal intensive care unit(NICU).Method From January 2020 to December 2021,3 682 neonates(1 794 full-term infants and 1 888 premature infants)admitted to NICU,the Seventh Medical Center of PLA General Hospital were selected as the observation objects.Dry blood plaques were collected and screened for MS/MS genetic metabolic disease.Urine GC-MS was detected in the neonates with positive samples after initial screening.Biochemical diagnosis was made according to metabolic profile and clinical manifestations.Statistical method performed by χ2 test.Result Among the 3 682 NICU infants,the positive rate of primary screening was 5.65%(208/3 682),and the positive rate of secondary screening was 1.33%(49/3 682).There were 14 cases with co-biochemical diagnosis of IMD,and the total detection rate was 0.38%(14/3 682).The detection rate of full-term infants was higher than that of preterm infants[0.67%(12/1 794)vs 0.11%(2/1 888),χ2=7.697,P=0.006].Among the 14 cases of IMD,11 cases had abnormal organic acid metabolism,including 8 cases(57.1%)of methylmalonate acidemia,2 cases(14.3%)of glutaracidemia and 1 case of 3-methylpentadienuria(7.1%).There were 3 cases of abnormal amino acid metabolism,including 2 cases(14.3%)of urea cycle disorder and 1 case(7.1%)of hyperphenylalaninemia.The false positive rate of MS/MS preliminary screening was 5.29%(194/3 668),and the positive predictive value was 6.73%(14/208).After the recall,the false positive rate was 0.95%(35/3 668),and the positive predictive value was 28.57%(14/49).The positive predictive value of increased propionylcarnitine and its ratio and glutarylcarnitine was higher than that of abnormal amino acid metabolism among various MS/MS indexes.Conclusion The incidence of IMD in NICU population is high,and there are many non-genetic factors such as preterm birth and infection,which can interfere with the results of MS/MS metabolic screening.Timely MS/MS reexamination and urine GC-MS analysis can improve diagnostic efficiency and clarify biochemical diagnosis.
Newborn screeningInherited metabolic disordersTandem mass spectrometryGas phase mass spectrometryNeonatal intensive care unit
国家科技期刊平台
NSTL
万方数据
维普
