Reducing False Positives in Newborn Screening for Lysosomal Storage Disorders

Reducing false positives in newborn screening for lysosomal storage disorders

This poster was presented at WORLDSymposium 2020 in Orlando, FL.

Authors: J. Washburn, C. Brannen, A. Bhattacharjee
Baebies, Inc., Durham, NC, USA

As newborn screening (NBS) expands to include lysosomal storage disorders, NBS programs are evaluating options to reduce false positive results in first-tier enzymatic screening.

  • Variables such as seasonality, age at sample collection, and birth weight can affect enzyme activity. Consideration of these variables during assignment of decision thresholds can reduce false positives.
  • Current testing platforms cannot easily separate pseudodeficiencies from true positive results nor predict the risk for very early onset forms of disease – such as infantile onset Pompe disease – which require early intervention for optimal outcomes.

We performed a deep characterization of the a-glucosidase (GAA) enzyme and gene sequence in order to have more confidence in screening assay performance and results delivered.

To reduce false positives and provide customizable patient referral, NBS programs should consider the combination of 1) optimization of first-tier cutoffs to account for seasonality and demographics variables, and 2) integration of second-tier targeted next generation sequencing.