Screening of metabolic diseases in newborn age.

1. Big picture

Newborn screening is one of the most successful preventive programs in pediatrics.

The goal is:

Apparently healthy newborn
        ↓
Detect disease BEFORE symptoms develop
        ↓
Start treatment early
        ↓
Prevent death, intellectual disability,
growth failure, organ damage, and metabolic crisis

Most screened disorders are rare but treatable. Without screening, many affected infants appear normal at birth and become symptomatic only after irreversible damage has occurred.

Exam principle: A positive screening test is not diagnostic. It identifies infants who need confirmatory testing.

2. Definition