Non-SCID conditions associated with SCID NBS

ClassificationFindings
Syndromes with low T-cell numbersRecognized genetic syndrome that includes variable immune defects, with some cases having significantly low T-cell numbers (DiGeorge syndrome, FOXN1, CHARGE syndrome, Trisomy 21, Jacobsen syndrome, RAC2 defect, DOCK8 deficiency, Ataxia Telangiectasia, VACTERL association, Barth syndrome, TAR syndrome, Ectrodactyly Ectodermal Dysplasia syndrome, Cartilage Hair Hypoplasia, others)
Secondary T-cell lymphopeniaCongenital malformation or disease process without an intrinsic defect in production of circulating T-cells (e.g. congenital heart disease with vascular leak, hydrops, gastroschisis, chylothorax, intestinal lymphangiectasia, others)
Preterm birth alonePreterm birth and low birth weight, with low T cell numbers early in life that normalize over time
Idiopathic T-cell lymphopenia (formerly called Variant SCID)Persistently low T cell numbers for over 3 months without recognized cause
In all of these other conditions there is 1) no maternal engraftment, 2) the T cells are largely naive, 3) PHA proliferation is usually normal.