RT Book, Section A1 Jenks, Jennifer A1 Nadeau, Kari A2 Stevenson, David K. A2 Cohen, Ronald S. A2 Sunshine, Philip SR Print(0) ID 1109799522 T1 Severe Combined Immunodeficiency (SCID) T2 Neonatology: Clinical Practice and Procedures YR 2015 FD 2015 PB McGraw-Hill Education PP New York, NY SN 9780071763769 LK accesspediatrics.mhmedical.com/content.aspx?aid=1109799522 RD 2022/05/19 AB Severe combined immunodeficiency (SCID) is a fatal primary immune condition characterized by the absence of both humoral and cellular immunity with severe lymphopenia. Patients with SCID have reduced numbers and function of both T and B lymphocytes (and in some cases, natural killer [NK] cells) and hypogammaglobulinemia. If left untreated, babies with SCID most often die within 1 to 2 years of life because of severe, recurrent infections.