Immunology ReportsFatal Pneumocystis jirovecii and Cytomegalovirus Infections in an Infant With Normal TRECs Count Pitfalls of Newborn Screening for Severe Combined ImmunodeficiencyMendez-Echevarria, Ana MD, PhD*; Gonzalez-Granado, Luis Ignacio MD†; Allende, Luis M. MD‡; De Felipe, Beatriz PhD§; Teresa, Del Rosal MD, PhD*; Calvo, Cristina MD, PhD*; Perez-Martinez, Antonio MD, PhD¶; Raquel, Ruiz-Garcia MD‡; Neth, Olaf MD, PhD‖ Author Information From the *General Paediatrics and Infectious and Tropical Diseases Department, Hospital La Paz-IdiPAZ, Madrid, Spain †Pediatric Infectious Diseases and Immunodeficiencies Unit ‡Immunology Department, Hospital Universitario 12 de Octubre, Madrid, Spain §Paediatric Infectious Diseases Unit, Rheumatology and Immunodeficiencies Department, Hospital Infantil Universitario Virgen del Rocio, Instituto de Biomedicina, Seville, Spain ¶Pediatric Hematology and Oncology Department, Hospital La Paz-IdiPAZ, Madrid, Spain ‖Paediatric Infectious Diseases, Rheumatology and Immunodeficiencies Department, Hospital Infantil Universitario Virgen del Rocio, Instituto de Biomedicina, Seville, Spain. Accepted for publication March 21, 2018. The authors have no funding or conflicts of interest to disclose. A.M.-E. and G.-G.L.I. are shared first authors. Address for correspondence: Ana Mendez-Echevarria, MD, PhD, General Paediatrics and Infectious and Tropical Diseases Department, Hospital La Paz-IdiPAZ, Paseo de la Castellana 261, 28046 Madrid, Spain. E-mail: [email protected]. The Pediatric Infectious Disease Journal: February 2019 - Volume 38 - Issue 2 - p 157-160 doi: 10.1097/INF.0000000000002058 Buy Metrics Abstract Newborn screening for severe combined immunodeficiency using T-cell receptor excision circles allows prompt diagnosis and initiation of supportive and curative therapy thereby reducing morbidity and mortality. However, profound combined immunodeficiencies with normal numbers of nonfunctional T cells will go undetected. We present a patient with calcium release-activated calcium channel gene (ORAI1) deficiency and normal T-cell receptor excision circle numbers observed after diagnosis at the age of 14 months who suffered from disseminated fatal cytomegalovirus and Pneumocystis jirovecii infection, demonstrating a potential pitfall of the current newborn screening program. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.