Objective To explore the incidence and prognosis of citrin deficiency in Maoming,and to understand mutation types and frequency of SLC25A13 gene.Methods A total of 88 322 newborns born in Maoming from April 2022 to January 2025 were selected as research subjects.These specimens were screened using tandem mass spectrometry.Newborns with elevated citrulline levels or suspected clinical symptoms of citrin deficiency were recalled immediately for further genetic confirmation,and treated confirmed cases were followed up.Results Among 88 322 newborns,53 cases were positive for citrulline by tandem mass spectrometry,43 cases were recalled with positive initial screening,23 cases were still positive for citrulline after re-examination.Finally,1 case of neonatal intrahepatic cholestasis caused by citrin deficiency(NICCD)was clinically diagnosed,and 10 cases were diagnosed with SLC25A13 gene,of which 1 case was false negative.Therefore,the total positive predictive value was 18.87％(10/53),and the prevalence rate of NICCD in Maoming was 1/8029(11/88 322).A total of 5 mutation sites were detected in 10 neonates with NICCD gene diagnosis,and the top 3 mutation sites in the order of proportion were:c.852-855delTATG accounted for 65.0％(13/20),c.615+5G>A accounted for 15.0％(3/20),IVS16ins3kb accounted for 10.0％(2/20).Among the 11 cases,1 case refused treatment and died of liver failure,while the remaining 10 cases were developing well after standardized treatment.Conclusion The incidence of neonatal citrin deficiency in Maoming is significantly higher than in other areas.Tandem mass spectrometry enables rapid early detection of citrin deficiency,though false-negative results may occur in individual cases.Combining genetic sequencing can improve diagnostic accuracy,and achieve precise management of inherited metabolic diseases.

Objective To explore the incidence and prognosis of citrin deficiency in Maoming,and to understand mutation types and frequency of SLC25A13 gene.Methods A total of 88 322 newborns born in Maoming from April 2022 to January 2025 were selected as research subjects.These specimens were screened using tandem mass spectrometry.Newborns with elevated citrulline levels or suspected clinical symptoms of citrin deficiency were recalled immediately for further genetic confirmation,and treated confirmed cases were followed up.Results Among 88 322 newborns,53 cases were positive for citrulline by tandem mass spectrometry,43 cases were recalled with positive initial screening,23 cases were still positive for citrulline after re-examination.Finally,1 case of neonatal intrahepatic cholestasis caused by citrin deficiency(NICCD)was clinically diagnosed,and 10 cases were diagnosed with SLC25A13 gene,of which 1 case was false negative.Therefore,the total positive predictive value was 18.87％(10/53),and the prevalence rate of NICCD in Maoming was 1/8029(11/88 322).A total of 5 mutation sites were detected in 10 neonates with NICCD gene diagnosis,and the top 3 mutation sites in the order of proportion were:c.852-855delTATG accounted for 65.0％(13/20),c.615+5G>A accounted for 15.0％(3/20),IVS16ins3kb accounted for 10.0％(2/20).Among the 11 cases,1 case refused treatment and died of liver failure,while the remaining 10 cases were developing well after standardized treatment.Conclusion The incidence of neonatal citrin deficiency in Maoming is significantly higher than in other areas.Tandem mass spectrometry enables rapid early detection of citrin deficiency,though false-negative results may occur in individual cases.Combining genetic sequencing can improve diagnostic accuracy,and achieve precise management of inherited metabolic diseases.