Newborn Screening

Newborn screening (NBS) for CF is essential for early detection and treatment, which can improve health outcomes. In many countries, including the US, it is mandatory to screen for CF. [10][15]

• Sample collection: newborn blood spot test, performed via heel prick blood sampling in the first 24 and 48 hours of life

• Screening tests [16]

  • Immunoreactive trypsinogen (IRT) : initial screening test

    • An immunofluorescence assay that measures levels of IRT [17]

    • Normal IRT levels: CF unlikely

    • Elevated IRT levels: CF possible; additional screening tests required [16]

  • CFTR mutation testing (DNA testing): second-tier screening test

    • Identifies the most common CF-causing CFTR mutations, including CF carriers

    • Cannot detect uncommon CFTR mutations that are not included on the panel.

• Screening protocols: a combination of CF screening methods to minimize false-positive and false-negative NBS results [18]

• Next steps after positive NBS: Refer patients promptly to a specialist for a complete diagnostic workup and to start treatment if required.