1. Changing the Time of Newborn Screen Collection A Data-Driven and Safety-Oriented Approach
Emeril Santander
Michael Kowalski
Laure Tessier
Jennifer Milburn
Pranesh Chakraborty

2. Objectives
Describe current sampling guidelines and the importance of timely screening in the context of Ontario’s universal newborn screening program
Describe results of a four-part approach taken to determine safety of earlier screening

3. Screening for Disease Screening in general: Detects treatable disease
Significantly speeding diagnosis & treatment
As early as possible
Prior to onset of severe or irreversible
health outcomes
When delivery of treatment is most effective
As accurately as feasible
Screen Positives likely to be truly affected by disease
Screen Negatives likely to be unaffected by disease
A cost-effective way to identify elevated risk
We screen because we can’t diagnostically test everyone, however everyone is at risk. We accept the tradeoffs of screening to instead extend risk identification to everyone.

4. Newborn Screening in Ontario
Shortly After Birth
A small sample of blood is taken

5. Newborn Screening in Ontario
The sample of blood is dropped on to a special type of paper on the newborn screening card
These cards are pre-distributed to all neonatal healthcare providers in the province
Not just ‘The PKU Test’
Expanded panel in 2006 and 29 genetic diseases now tested based on 100+ biomarkers
Central public health laboratory model based in Ottawa
Universal population-based screening with >99% of newborns tested .

6. Newborn Screening in Ontario
Health care provider fills out information about the baby on the card, including datetime of birth and collection

7. Newborn Screening in Ontario
The newborn screening sample is sent to Newborn Screening Ontario (NSO) in Ottawa for testing. Overnight courier service is used.

8. Newborn Screening in Ontario
At the lab, several techniques are applied to evaluate for risk of metabolic, immune, endocrine, and other diseases.
Up to 1200 samples per day

9. Newborn Screening in Ontario
SCREEN POSITIVE PATIENTS
SCREEN NEGATIVE PATIENTS
Are referred to specialist care at one of five regional treatment centres
Kingston General Hospital
Toronto Sick Kids
Ottawa Children’s Hospital
London Health Sciences
Hamilton Health Sciences
Diagnostic Testing
Healthcare Provider notified
Healthcare Provider Receives Negative Report
Again, more than 99% of Ontario’s 140,000 yearly births will be negative.

10. Part II. Sampling and time-sensitive screening

11. babies are born each year in Ontario
Working Against the Clock
Aggressive Diseases:
Maple Syrup Urine Disease (MSUD)
Medium-Chain acyl-CoA dehydrogenase deficiency (MCADD)
Propionic Acidemia (PA)
Methylmalonic Acidemia (MMA)
Galactosemia (GALT)
Tyrosinemia (TYR)
Citrullinemia (CIT)
ASA Lyase Deficiency (ASA)
Congenital Adrenal Hyperplasia (CAH)
Approximately
babies are born each year in Ontario
~ 250 babies
will have a disease
~1500
babies will
screen positive
If detected and treated early, affected infants may have health outcomes similar to unaffected infants. If not detected or treated,

12. The Urgency of Detection
Among the 250 infants detected each year truly affected by a screened disorder:
5% – 10%
May die in the first week of life
10% – 20%
Will be symptomatic in this first week
Among the screened disorders, 20 of them have potential to cause irreversible harm in first two weeks of life

13. The Newborn Screening Sequence

14. The Newborn Screening Sequence
NSO now works 7 days per week
New software tracks all packages en-route
NSO refers critical patients on weekends
BORN-supported electronic referral and diagnostic tracking

15. 24 - 72 h 24 - 48 h Timely Collection  Timely Screen after birth
Historical Guideline h
after birth
New Guideline h
after birth

16. Part III. Screening earlier, safely
New Guideline
Systematic Review
Longitudinal Analysis
Impact Forecasts
Review Peer Practices
Part III. Screening earlier, safely

17. A. Reviewing the literature
New Guideline
Systematic Review
Longitudinal Analysis
Impact Forecasts
Review Peer Practices
A. Reviewing the literature

18. Reviewing the literature – Methods and results
534 records identified in MEDLINE
29 records identified from other sources
5 records after duplicates removed
558 records screened
72 full-texts assessed
-Literature search: to determine whether there was any evidence that collecting DBS at 24h of age could increase the risk of false-negative results for disorders on the NSO panel
-MEDLINE database search, and identified some articles using other sources -> team’s pre-existing knowledge of existing articles answering our research question, ScienceDirect Cited Srticles and Recommander search tool for those articles, and reference scans of the retained articles
-Research question divided into 2 searches: one to find evidence of false-negative results or sensitivity reports with sample collection at 24h of age, one to find evidence of the NSO primary analyte levels in the first 24h of age (to compare them with current NSO cut-offs)
-Searches conducted for every disease on the NSO panel except galactosemia and hemoglobinopathies
-Records identified with other resources were not identified by our MEDLINE search
12 full-texts included in literature review

19. Conclusions
No evidence that collecting dried bloodspot samples at 24 hours of age would increase NSO’s false-negative rate
Some evidence suggests that collecting samples at 24 hours of age would not increase the false-negative rate for PKU and CH (based on analyte values measured at 24 hours of age)
Limitations: two reviewers for screening, only one reviewer for full texts (this is a rapid review), search did not seem systematic
Next step: turning this into a systematic review

20. B. newborns with multiple samples
New Guideline
Systematic Review
Longitudinal Analysis
Impact Forecasts
Review Peer Practices
B. newborns with multiple samples

21. Finding Age Effects on Biomarkers
The ideal observational study*:
Follow a large sample of newborns
With disease and without disease
Prick heel of each every hour
in the first 72 hours of life
Check for differences in biomarker levels by postnatal age
Determine if sampling age would change sensitivity or specificity of screening test
* We can’t do this.

22. Finding Age Effects on Biomarkers
Instead:
Retrospective Cohort
553 newborns between
Sampled more than once in first 72 hours of life ‘by chance’
 No obvious reason for multi-sampling
Samples linked in system using demographics

23. Biomarker X Patient 1 Biomarker Value HIGH 24 hours 48 hours 72 hoursuL
X at T1
X at T2 24
hours 48
hours 72
hours
Postnatal Age in Hours

24. Biomarker X Patient 1 Biomarker Value HIGH 24 hours 48 hours 72 hoursuL
X at T1
X at T2 24
hours 48
hours 72
hours
Postnatal Age in Hours

25. Biomarker X Patient 1 … Patient 553 Biomarker Value HIGH 24 hours 48….
HIGH
Patient 553
Biomarker
Value uL 24
hours 48
hours 72
hours
Postnatal Age in Hours

26. Biomarker X Biomarker X 72h trend Biomarker Value HIGH 24 hours 48uL 24
hours 48
hours 72
hours
Postnatal Age in Hours

27. No Difference in Screening Performance When Trend is Stable
Biomarker X
HIGH
Screen Positive Cutoff
Values above this line
are at elevated risk
Biomarker
Value uL 24
hours 48
hours 72
hours
Postnatal Age in Hours

28. Increased Risk of False Positive Results When Trend is Negative
Biomarker X
HIGH
Screen Positive Cutoff
Values above this line
are at elevated risk
Biomarker
Value uL 24
hours 48
hours 72
hours
Postnatal Age in Hours

29. Increased Risk of False Negatives With Upward Trend
Biomarker X
HIGH
Screen Positive Cutoff
Values above this line
are at elevated risk
Biomarker
Value uL 24
hours 48
hours 72
hours
Postnatal Age in Hours

30. Thyroid Stimulating Hormone (TSH) Biomarker for Congenital Hypothyroidism(CH)
True Negative
False Positive
True Positive

31. Thyroid Stimulating Hormone (TSH) Biomarker for Congenital Hypothyroidism(CH)
True Negative
False Positive
True Positive

32. Postnatal TSH Elevation
A well-known endocrine response to birth
The postnatal tsh rise begins 30 minutes following birth and is thought to be a response to the cold of the extrauterine environment

33. Summary Repeating this modelling across all screened biomarkers:
Certain endocrine markers will be elevated at an earlier age (false positive risk)
Potentially higher referral, recall, & diagnostics
Most trends were stable
No false negative risks identified

34. C. Predicting future screening performance
New Guideline
Systematic Review
Longitudinal Analysis
Impact Forecasts
Review Peer Practices
C. Predicting future screening performance

35. Background & goals
Goal: Identify the impacts on screening performance caused by more samples being collected earlier
Background:
85% of samples in 2015 were collected hours after birth
This number has grown by ~ 5%/yr since 2010 (…earlier discharges?)
There are no systematic individual differences in infants collected hours vs hours.

36. Background & goals Key points (cont.):
Proportional indicators of screening performance in the 24-48h interval have remained stable, even as more samples are collected in this window
SPP24-48: 0.01% (screen positive rate)
SNR24-48: 99.99% (screen negative rate)

37. Method & Conclusion
To forecast future performance we take the relevant proportions from the 24-48h interval and multiply them by the expected volumes of samples Conclusion: Most referrals will remain at current levels. Certain endocrine referrals may increase, although further optimization may be possible.

38. D. sampling practices in other screening programs
New Guideline
Systematic Review
Longitudinal Analysis
Impact Forecasts
Review Peer Practices
D. sampling practices in other screening programs

39. American Sampling Practices
Research Question: Is this a common practice in other screening laboratories in North America? Method: Database review (NEWSteps) & survey Results: 93% of US jurisdictions collect newborn screening samples at hours.

40. 24 - 48 h Summary & Conclusion after birth Screening is time-sensitive
New Guideline h
after birth
Screening is time-sensitive
Reducing age at sampling is safe, we checked!
Certain false positives may occur, but work to mitigate these is ongoing
Screening at hours is a widely-adopted practice in peer screening programs