Diagnosis

  • A screening test is performed on a newborn blood spot sample for the measurement of thyroid stimulating hormone (TSH). A high TSH suggests hypothyroidism.
  • Confirmatory tests:
    • Pre-treatment thyroid function tests (TSH and free thyroxine fT4).
    • Quantitative thyroglobulin (TG)
  • Optional confirmatory tests may include:
    • Thyroid imaging (ultrasound and/or radio-isotope scans of the neck, sub-lingual and upper chest area).
    • Thyroid autoantibodies (thyroid peroxidase and TSH receptor antibodies) in the infant (and if indicated in the mother).
    • Maternal TFTs
  • Genetic testing

Treatment

Replacement therapy with levothyroxine (thyroxine, L-thyroxine, LT4).