TABLE 4.

Characteristics, Treatments, and Outcomes of 49 Infants With SCID Diagnosed by Using NBS

SCID Genotype (No. Cases)	SCID Phenotypea	Nursery	TREC Result		Outcome After Treatmentb
			Urgent Positivec	Positive	Died (Posttransplant d, Cause)	Full T and B Cell Recovery and Off IgG, Treatmentd	T but Not B Cells Reconstituted, Still on IgG, Treatment
IL2RG (14)	Typical	Regular	12	0	1 (218 d, SOSe, CMV)	2 cond MUD, 1 GT, 1 cond MUD after GT	6 MMRD, 1 cond MUDf, 1 GT, 1 GT after MMRD
		NICU	2	0
ADA (9)	Typical	Regular	5	2	0	8 GT, 1 MSD	0
		NICU	1	0
	Leaky	Regular	0	1
RAG1 (8)	Typical	Regular	2	0	1 (28 d, SOS)	1 cond MSD	0
	Leaky	Regular	2 leaky, 1 Omenn syndrome	1 leaky, 2 Omenn syndrome	0	4 cond MMRD	2 cond MMRD (1 of whom planning to stop IgG)
IL7R (6)	Typical	Regular	5	0	0	4 MMRD, 1 MUD, 1 cond MSD after MSD	0
	Typical	NICU	0	1
JAK3 (3)	Typical	Regular	3	0	0	1 cond MSD, 1 cond MUD	1 MMRD
RAG2 (3)	Typical	Regular	2	0	0	1 MSD, 2 cond MUD	0
	Leaky	Regular	0	1
BCL11B (1)	Leaky	Regular	1	0	0	1 cond MUD	0
RMRP (1)	Leaky	Regular	0	1	0	1 cond MUD	0
Unknown (4)	Typical	Regular	1	1	1 (69 d, CMV)	0	1 cond MUD planning to stop IgG
		NICU	1	0	0	0	1 Cond MUD
	Leaky	Regular	1	0	0	0	1 cond MUD planning to stop IgG

Cond, conditioning with busulfan chemotherapy and, in some instances, fludarabine or other agents; MMRD, mismatched related donor; MSD, matched sibling donor; MUD, matched adult or cord blood unrelated donor.

^aCriteria from the PIDTC for typical SCID and leaky SCID; Omenn syndrome, a subset of leaky SCID, includes erythroderma rash, adenopathy, oligoclonal T-cell expansion, eosinophilia, and elevated immunoglobin E levels.

^bOne infant not included in this table had urgent-positive TRECs and the T⁻B⁻NK⁺ SCID lymphocyte profile but left the United States before HCT; no genotype or follow-up is available.

^cThree or fewer TREC copies with a normal control polymerase chain reaction copy number by the EnLite kit assay or equivalent with a previous in-laboratory assay.

^dTreatments included GT with low-dose busulfan followed by autologous CD34⁺ bone marrow cells transduced with a correct copy of the mutated gene (IL2RG or ADA), MMRD (usually a parent who is haploidentical), MSD, MUD. Cond, conditioning with busulfan chemotherapy and (in some instances) fludarabine or other agents (other infants may have had serotherapy with rabbit antithymocyte globulin or anti-CD52).

^ePosttransplant hepatic sinusoidal obstruction syndrome after busulfan chemotherapy.

^fOne patient left the United States after conditioned MUD HCT and reconstitution; it is not known if the patient is still on IgG.