Related Experiment Video
Updated: Jun 23, 2025
One-step Metabolomics: Carbohydrates, Organic and Amino Acids Quantified in a Single Procedure
Published on: June 25, 2010
The Benefit of Detecting Reduced Intracellular B12 Activity through Newborn Screening Remains Unclear
Stella Knöpfli1, Bernadette Goeschl2, Maximilian Zeyda2
1Division of Metabolism and Children's Research Center, University Children's Hospital of Zurich, University of Zurich, 8032 Zurich, Switzerland.
Insights
Newborn screening for Vitamin B12 deficiency (B12D) can identify affected infants, but no developmental benefits were proven. Assessing maternal B12 status during pregnancy is recommended to prevent unnecessary infant diagnostics.
Area of Science:
- Biochemistry
- Pediatrics
- Public Health
Background:
- Vitamin B12 deficiency (B12D) can negatively impact early childhood development.
- Newborn screening (NBS) programs can detect inborn errors of cobalamin metabolism, including B12D.
Purpose of the Study:
- To evaluate the effectiveness of NBS in detecting B12D and its impact on infant development.
- To identify predictors of B12D in newborns.
Main Methods:
- Retrospective analysis of 59 neonates with suspected B12D via NBS.
- Recorded NBS and recall biomarkers, including age at sampling and methionine/phenylalanine ratio.
- Assessed infant growth and psychomotor development using Vineland III scales.
Main Results:
- Of 59 suspected cases, B12D was confirmed in 15 (25%), not confirmed in 28 (48%), and not investigated in 16 (27%).
- Age at sampling and the methionine/phenylalanine ratio were key predictors of B12D (67.4% accuracy).
- No significant differences in growth or psychomotor development were observed between confirmed, unconfirmed, or control groups.
Conclusions:
- While NBS can detect reduced intracellular B12 activity, its advantage for infant cognitive development or growth remains unproven.
- Low maternal B12 intake was common.
- Assessing maternal B12 status during pregnancy is advisable to avoid unnecessary neonatal investigations.
Abstract:
Vitamin B12 (B12) deficiency (B12D) can have detrimental effects on early growth and development. The Austrian newborn screening (NBS) program targets inborn errors of cobalamin metabolism and also detects B12D. Of 59 included neonates with B12D suspected by NBS, B12D was not further investigated in 16 (27%) retrospectively identified cases, not confirmed in 28 (48%), and confirmed in 15 (25%) cases. NBS and recall biomarkers were recorded. Age at sampling of the dried blood spots for NBS and the 1st-tier methionine/phenylalanine ratio were the strongest parameters to predict B12D (67.4% correct allocations). No differences between cases with confirmed, unconfirmed, or unknown B12D or differences to norms were observed for growth and psychomotor development (Vineland III scales, phone interviews with parents of children between months 10 and 14 of life). B12 intake was below recommendations in most mothers. NBS can detect reduced intracellular B12 activity. No advantage of NBS detection and treatment regarding infant cognitive development or growth could be proven. Since conspicuous NBS findings cannot be ignored, and to prevent exposing newborns to invasive diagnostics, assessment of maternal B12 status during pregnancy seems advisable.
