Newborn screening strategies for congenital hypothyroidism: an update
- 734 Downloads
It is the purpose of this article to briefly review the initial development and subsequent evolution of newborn screening programs to detect infants with congenital hypothyroidism (CH) and then to provide an update of the advantages and disadvantages of the main test strategies. Pilot programs began screening newborn populations in North America in the mid-1970s using either primary thyroxine (T4)-follow-up thyroid stimulating hormone (TSH) or primary TSH testing. Many programs in the United States and around the world continue to prefer a primary T4-follow-up TSH test strategy. This approach has the advantage of detecting infants with primary CH, as well as cases of hypopituitary hypothyroidism, by follow-up of infants with a T4 below an absolute cutoff or with a persistently low T4 level, necessitating a higher recall rate. With increasing assay sensitivity and specificity, several programs in the United States and worldwide have elected to switch to a primary TSH test strategy. This test strategy has the advantage of detecting primary CH and subclinical hypothyroidism and at a lower recall rate. Programs considering switching to a primary TSH test strategy need to develop age-related TSH cutoffs to maintain an acceptable recall rate. Both test strategies have the potential to detect infants with CH characterized by “delayed TSH rise,” but only if they collect a routine or discretionary second specimen, now recommended in low-birth-weight and acutely ill infants. Lastly, a lower TSH cutoff appears to be one of the explanations for the recently described increased incidence of CH.
KeywordsThyroid Stimulate Hormone Newborn Screening Recall Rate Subclinical Hypothyroidism Congenital Hypothyroidism
Dried blood spot
National Newborn Screening and Genetics Resource Center
Thyroid stimulating hormone
- Chiesa A, Prieto L, Papendieck P, Gilligan G, Niremberg M, Gruneiro-Papendieck L (2009) Characterization of thyroid disorders found by primary congenital hypothyroidism (CH) neonatal screening: Something is changing? Revi Invest Clin 61(Suppl 1):30Google Scholar
- Fukushi M, Fujikura K, Hanai J, Yano K, Tamima T, Fujieda K (2009) Neonatal screening for congenital hypothyroidism by measurement of TSH and free T4. Rev Invest Clin 61(Suppl 1):30Google Scholar
- Hunter MK, Mandel SH, Sesser DE, et al. (1998) Follow-up of newborns with low thyroxine and non-elevated thyroid-stimulating hormone-screening concentrations: Results of the 20-year experience in the Northwest Regional Newborn Screening Program. 132:70–74.Google Scholar
- Klein AG, Foley TP Jr (1975) Letter: Screening for hypothyroidism. J Pediatr 87:667–668Google Scholar
- Lanting CI, van Tijn DA, Loeber JG, Vulsma T, de Vijlder JJ, Verkerk PH (2005) Clinical effectiveness and cost-effectiveness of the use of the thyroxine/thyroxine-binding globulin ratio to detect congenital hypothyroidism of thyroidal and central origin in a neonatal screening program. Pediatrics 116(1):168–73CrossRefPubMedGoogle Scholar
- Miyai K, Oura T, Kawashima M, et al. (1978) A new method of paired thyrotropin assay as a screening test for neonatal hypothyroidism. J Clin Endocrinol Metab 47:1028-1033Google Scholar
- National Newborn Screening and Genetics Resource Center (NNSGRC), 2009 National Newborn Screening Information System (http://genes-r-us.uthscsa.edu).
- Vulsma T, Gons MH, deVijlder JJM (1989) Maternal-fetal transfer of thyroxine in congenital hypothyroidism due to a total organification defect or thyroid agenesis. N Engl J Med (321):13–16Google Scholar
- Wiley V, Bijarnia S, Wikcken B (2009) Screening for hypothyroidism in very low birth weight babies. Rev Invest Clin 61(Suppl 1):31Google Scholar