Table 1.
NBS for MPSs by first-tier enzymatic activity versus GAG biomarker analysis.
| MPS First-Tier NBS Method | Number of 3 mm DBS punches per newborn | Reagent Costs per Newborn2 | Analysis Time2 | LC-MS/MS instrument models required2 | False positive rate after first-tier NBS2 | Additional comments |
|---|---|---|---|---|---|---|
| Internal Disaccharide GAG LC-MS/MS Analysis | 2 | $0.46 | Results are ready in the morning of day 3 at a throughput of 429 newborns per LC-MS/MS instrument | PerkinElmer QSight 400 series, Waters TQ-S, Sciex 5500 | MPS-I and -II (1.6%) MPS-IIIA-D (4.9%) MPS-IVA (7%) MPS-VI and -VII (0%) TOTAL 13.5% |
GAG analysis requires a dedicated LC-MS/MS station with chromatography appropriate for gAg fragments. |
| Multiplex LC-MS/MS Enzymatic Activity | 2 | $6.00 (including GM1-gangliosidosis) | Similar for first-tier GAG NBS | Waters TQD or Xevo TQ | MPS-I (0.004%) MPS-II (0.017%) MPS-IIIA (0.017%) MPS-IIIB (0%) MPS-IIIC (0.017%) MPS-IVA (0.0076%) MPS-VI (0.0038%) MPS-VII (0%) TOTAL 0.07% |
Multiplexable with many other non- MPS diseases. |
1
GAG first-tier analysis also finds multiple sulfatase deficiency but not GM1- gangliosidosis, but enzymatic activity first-tier analysis finds both.
2
Full details of the estimation is provided as Supplemental Material.