TABLE 1.
Values of informative screening markers and ratios (median and percentiles) of 1 963 461 newborns screened for MSUD (including false‐positive referrals), false‐positive referrals (n = 118), and MSUD patients (n = 4)
| 2007‐2017 screening | Screened newborns (n = 1 963 461) a | False‐positives (n = 118) | MSUD patients (n = 4) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Markers and ratios | Median | 99.9th perc | 99.99th perc | Median | 95th perc | Patient 1 | Patient 2 | Patient 3 | Patient 4 |
| Xle | 159 | 372 | 450 | 451 | 838 | >1200 | >1200 | 947 | 697 |
| Val | 129 | 354 | 443 | 449 | 643 | 543 | 467 | 548 | 430 |
| (Xle + Val)/(Phe + Tyr) | 2.04 | 4.43 | 5.97 | 3.06 | 6.34 | >17.09 | >18.32 | 11.59 | 6.55 |
| Xle/Tyr | 1.83 | 8.10 | 19.50 | 2.45 | 11.11 | >27.91 | >22.64 | 13.15 | 6.28 |
| Xle/Phe | 2.96 | 5.82 | 6.71 | 3.82 | 5.64 | >20.34 | >31.58 | 16.61 | 11.43 |
| Val/Phe | 2.41 | 5.41 | 6.38 | 3.99 | 5.86 | 9.2 | 12.29 | 9.61 | 7.05 |
Note: Xle and Val concentrations and cut‐off values in μmol/L blood.
Abbreviations: MSUD, maple syrup urine disease; Phe, phenylalanine; Tyr, tyrosine; Val, valine; Xle, total leucine.
a
Excluding four true‐positive referrals.