YIN-HSIU CHIENChiang S.-C.Chang K.-L.HSIN-HUI YULee W.-I.Tsai L.-P.Hsu L.-W.Hu M.-H.WUH-LIANG HWU2020-12-162020-12-1620150929-6646https://www.scopus.com/inward/record.uri?eid=2-s2.0-84921433749&doi=10.1016%2fj.jfma.2012.10.020&partnerID=40&md5=d4ec3a6b549ef47b3859730843fed820https://scholars.lib.ntu.edu.tw/handle/123456789/525856Background/Purpose: In order to know the true incidence of severe combined immunodeficiency (SCID) in a Chinese population, we conducted and implemented SCID newborn screening in Taiwan. Methods: Between May 1, 2010 and December 31, 2011, the National Taiwan University Hospital Newborn Screening Center screened all newborns for T-cell lymphopenia by measuring the copy number of T-cell receptor excision circles (TRECs) and RNase P. Newborns with low TREC values were subjected to complete blood cell counts and flow cytometry. Results: A total of 106,391 newborns were screened using the TREC assay over a period of 19 months. Five newborns were immediately referred for confirmatory tests, including two SCID patients and two patients with persistent T-cell lymphopenia; a third SCID patient was found 2 months after the study period. All three SCID cases received stem cell transplantation at the age of 2-5 months. We also identified five cases of 22q11.2 microdeletion syndrome. During this period, two SCID patients from among the unscreened newborns were reported, and they died at ages 3 months and 4 months, respectively. Conclusion: Newborn screening to measure the number of TREC copies successfully identifies newborns with T-cell lymphopenia, 22q11.2 microdeletion syndrome, and other high-risk conditions. Taken together, the incidence of T-cell lymphopenia in apparently healthy newborns is more than 1 in 11,821, and further attention to their immune functions is warranted. ? 2012.[SDGs]SDG3T lymphocyte receptor; Article; blood cell count; Chinese; chromosome deletion 22q11; clinical article; flow cytometry; human; incidence; lymphocytopenia; newborn; newborn screening; severe combined immunodeficiency; Taiwan; Asian continental ancestry group; female; infant; lymphocyte count; Lymphopenia; male; severe combined immunodeficiency; Asian Continental Ancestry Group; Female; Humans; Incidence; Infant; Infant, Newborn; Lymphocyte Count; Lymphopenia; Male; Neonatal Screening; Severe Combined Immunodeficiency; Taiwanjournal article10.1016/j.jfma.2012.10.020256185832-s2.0-84921433749