Table 2.
Number of true and false positive results modeled for a screening strategy based on reduced GALC activity and PSY at different cutoffs (≥2, 5, and 10 nM).
| PSY Cutoff |
GA | IL | KY | MO | NY | PA | TN | Total | |
|---|---|---|---|---|---|---|---|---|---|
|
Time
Period |
9/2021–6/2023 | 12/2017–9/2023 | 2/2016–6/2023 | 4/2020–5/2023 | 1/2021–6/2023 | 5/2021–5/2023 | 7/2020–5/2023 | ||
| # of Births | - | 219,399 * | 848,000 | 404,626 | 215,585 | 517,514 | 257,170 | 268,719 | 2,731,013 |
|
True
Positive Cases |
≥10 nM | 1 IKD ^ | 5 IKD ^ | 2 IKD | 1 IKD | 0 | 1 IKD | 1 IKD | 11 IKD ^ |
| ≥5 nM | 1 IKD ^ | 5 IKD ^, 2 LOKD ⁋ |
2 IKD | 1 IKD | 0 | 1 IKD, 1 LIKD |
1 IKD | 11 IKD ^, 1 LIKD, 2 LOKD |
|
| ≥2 nM | 1 IKD ^ | 5 IKD ^, 12 LOKD ⁋ |
2 IKD | 1 IKD | 1 LOKD ⁋ | 1 IKD, 3 LIKD 2 LOKD ⁋ |
1 IKD, 3 LOKD ⁋ |
11 IKD ^, 3 LIKD, 18 LOKD ⁋ |
|
|
False
Positive Cases |
≥10 nM | 0 | 0 | 0 | 2 # | 0 | 0 | 0 | 2 # |
| ≥5 nM | 0 | 0 | 0 | 2 # | 0 | 0 | 0 | 2 # | |
| ≥2 nM | 0 | 45 | 0 | 2 # | 0 | 0 | 1 | 48 # | |
| FPR | ≥10 nM | 0% | 0% | 0% | 0.001% | 0% | 0% | 0% | 0.0001% |
| ≥5 nM | 0% | 0% | 0% | 0.001% | 0% | 0% | 0% | 0.0001% | |
| ≥2 nM | 0% | 0.005% | 0% | 0.001% | 0% | 0% | 0.0004% | 0.002% | |
| Prevalence | All KD | 1:219,399 | 1:49,882 | 1:202,313 | 1:215,585 | 1:517,514 | 1:42,862 | 1:67,180 | 1:85,344 |
| IKD | 1:219,399 | 1:169,600 | 1:202,313 | 1:215,585 | - | 1:257,170 | 1:268,719 | 1:248,274 | |
| LIKD | - | - | - | - | - | 1:85,723 | - | 1:910,338 |
FPR, false positive rate; PSY, psychosine; * total number of live births was not provided by state and therefore calculated for the given time periods from: Hamilton BE et al. Births: Provisional data for 2019. Vital Statistics Rapid Release; no 8. Hyattsville, MD: National Center for Health Statistics. May 2020. Available from: https://www.cdc.gov/nchs/data/vsrr/vsrr-8-508.pdf, last accessed 16 January 2024; ^ parents of two IKD cases declined HSCT; ⁋ LOKD based on reduced GALC activity, moderately elevated PSY and supportive GALC genotype; # incl. two false positive cases caused by a laboratory error (see Discussion and Appendix A).