Kevin Stroek1, Annemieke C Heijboer1,2, Marelle J Bouva3, Catharina P B van der Ploeg4, Marie-Louise A Heijnen5, Gert Weijman6, Annet M Bosch7, Robert de Jonge8, Peter C J I Schielen3, A S Paul van Trotsenburg9, Anita Boelen1. 1. Endocrinology Laboratory, Department of Clinical Chemistry, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands. 2. Endocrinology Laboratory, Department of Clinical Chemistry, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, Vrije Universiteit, Amsterdam, the Netherlands. 3. Reference Laboratory Neonatal Screening, Center for Health protection, National Institute for Public Health and the Environment, Bilthoven, the Netherlands. 4. Netherlands Organization for Applied Scientific Research TNO, Department of Child Health, Leiden, the Netherlands. 5. Center for Population Screening, National Institute for Public Health and the Environment, Bilthoven, the Netherlands. 6. Department of Vaccine Supply and Prevention, National Institute for Public Health and the Environment, Bilthoven, the Netherlands. 7. Division of Metabolic Disorders, Department of Pediatrics, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands. 8. Department of Clinical Chemistry, Amsterdam UMC, Vrije Universiteit & University of Amsterdam, Amsterdam, the Netherlands. 9. Department of Paediatric Endocrinology, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands.
Abstract
OBJECTIVE: Congenital hypothyroidism (CH) is defined as thyroid hormone deficiency at birth due to disorders of the thyroid gland (thyroidal CH, CH-T), or the hypothalamus or pituitary (central CH, CH-C). The Dutch Newborn Screening (NBS) strategy is primarily based on determination of thyroxine (T4) concentrations in dried blood spots followed, if necessary, by thyroid-stimulating hormone (TSH) and thyroxine-binding globulin (TBG) measurement enabling detection of both CH-T and CH-C. A calculated T4/TBG ratio serves as an indirect measure for free T4. A T4/TBG ratio ≤ 17 in a second heel puncture is suggestive of CH-C. DESIGN AND METHODS: In the present study, we evaluated 11 years of Dutch CH NBS using a database of referred cases by assessing the contribution of each criterion in the unique stepwise T4-TSH-TBG NBS algorithm. RESULTS: Between 2007 and the end of 2017, 1 963 465 newborns were screened in the Netherlands. Use of the stepwise algorithm led to 3044 referrals and the identification of 612 CH cases, consisting of 496 CH-T, 86 CH-C, and 30 CH of unknown origin diagnoses. We detected 62.8% of CH-C cases by the T4/TBG ratio in the second heel puncture. The positive predictive value (PPV) of the stepwise T4-TSH-TBG NBS algorithm was 21.0%. CONCLUSION: This evaluation shows that the Dutch stepwise T4-TSH-TBG NBS algorithm with a calculated T4/TBG ratio is of great value for the detection of both CH-T and CH-C in the Netherlands, at the cost of a lower PPV compared to TSH-based NBS strategies.
OBJECTIVE: Congenital hypothyroidism (CH) is defined as thyroid hormone deficiency at birth due to disorders of the thyroid gland (thyroidal CH, CH-T), or the hypothalamus or pituitary (central CH, CH-C). The Dutch Newborn Screening (NBS) strategy is primarily based on determination of thyroxine (T4) concentrations in dried blood spots followed, if necessary, by thyroid-stimulating hormone (TSH) and thyroxine-binding globulin (TBG) measurement enabling detection of both CH-T and CH-C. A calculated T4/TBG ratio serves as an indirect measure for free T4. A T4/TBG ratio ≤ 17 in a second heel puncture is suggestive of CH-C. DESIGN AND METHODS: In the present study, we evaluated 11 years of Dutch CH NBS using a database of referred cases by assessing the contribution of each criterion in the unique stepwise T4-TSH-TBG NBS algorithm. RESULTS: Between 2007 and the end of 2017, 1 963 465 newborns were screened in the Netherlands. Use of the stepwise algorithm led to 3044 referrals and the identification of 612 CH cases, consisting of 496 CH-T, 86 CH-C, and 30 CH of unknown origin diagnoses. We detected 62.8% of CH-C cases by the T4/TBG ratio in the second heel puncture. The positive predictive value (PPV) of the stepwise T4-TSH-TBG NBS algorithm was 21.0%. CONCLUSION: This evaluation shows that the Dutch stepwise T4-TSH-TBG NBS algorithm with a calculated T4/TBG ratio is of great value for the detection of both CH-T and CH-C in the Netherlands, at the cost of a lower PPV compared to TSH-based NBS strategies.
Authors: Kevin Stroek; Annemieke C Heijboer; Marja van Veen-Sijne; Annet M Bosch; Catharina P B van der Ploeg; Nitash Zwaveling-Soonawala; Robert de Jonge; A S Paul van Trotsenburg; Anita Boelen Journal: Eur Thyroid J Date: 2021-03-05
Authors: Peter Lauffer; Nitash Zwaveling-Soonawala; Jolanda C Naafs; Anita Boelen; A S Paul van Trotsenburg Journal: Front Endocrinol (Lausanne) Date: 2021-09-09 Impact factor: 5.555