[Mass Screening for Inborn Errors of Metabolism]

Area of Science:

• Biochemistry
• Medical Diagnostics
• Public Health

Background:

• Neonatal mass screening aims to prevent serious infant disorders through early detection and treatment.
• The bacterial inhibition assay (BIA), developed around 1961, was historically used as the Guthrie method for newborn screening.
• Advancements in mass spectrometry have led to the replacement of BIA with tandem mass spectrometry (MS/MS) in many regions.

Purpose of the Study:

• To report on the nationwide implementation of tandem mass spectrometry for neonatal screening in Japan.
• To highlight the expansion of screening capabilities with the introduction of MS/MS.
• To present the initial outcomes of including new disease categories in the screening program.

Main Methods:

• Transition from the traditional bacterial inhibition assay (Guthrie method) to tandem mass spectrometry for neonatal screening.
• Nationwide implementation of the new screening technology across Japan.
• Inclusion of expanded testing panels for metabolic disorders.

Main Results:

• Successful nationwide introduction of tandem mass spectrometry for neonatal screening in Japan.
• The inclusion of 13 new diseases in the screening program.
• Positive initial results observed for fatty acid and organic acid metabolic disorders and urea cycle disorders.

Conclusions:

• The adoption of tandem mass spectrometry has significantly enhanced neonatal screening capabilities in Japan.
• The expanded screening panel allows for earlier identification of a wider range of congenital disorders.
• Early detection and treatment of newly included metabolic and urea cycle disorders are yielding favorable health outcomes for newborns.