Newborn screening for citrin deficiency and carnitine uptake defect using second-tier molecular tests

Table 2 Newborns with a positive second-tier screening for CUD

No.	First DBS free carnitine (μM)	p.R254X screening	Diagnosis
Positive 1^st screening
1	5.94	+	Lost to follow-up
2	5.23	-	Prematurity
3	3.27	-	Prematurity
4	4.51	-	Prematurity
Inconclusive 1^st screening
1	7.90	+	Normal
2	10.20	+	Normal
3	11.70	+	Normal
4	11.36	+	Normal
5	11.91	+	Normal
6	7.65	+	Normal
7	10.26	+	Normal
8	7.36	+	Normal
9	8.50	+	Normal
10	10.32	+	Normal
11	6.84	+	CUD (p.R254X/p.F17L)