ESPE Yearbook of Paediatric Endocrinology

J Clin Endocrinol Metab. 2022 Feb 17;107(3):638-648. doi: 10.1210/clinem/dgab798. PMID: 34726229

Brief Summary: This large monocenter retrospective cohort study (n=469) of patients diagnosed with congenital hypothyroidism (CH) identified predictors of transient vs. permanent CH. The authors developed a 4-item risk score (0-13 points) to be used from the age of 12 months on to predict transient CH during follow-up based on 1) screening TSH, 2) current LT4 dose (mcg/kg/d), 3) presence or absence of maternal thyroid disease, and 4) TSH values over the upper reference range between 6-12 months of age.

The incidence of transient CH has increased over the last two decades. Current guidelines recommend reevaluating patients without definitive permanent CH (athyreosis, hypoplasia, ectopy) between ages 2 to 3 years. Patients with thyroid gland in situ and a LT4 dose requirement < 3.0 mcg/kg/d at age 6 months may be reevaluated from age 6 months onwards [1,2]. The current work adds to these recommendations a detailed multivariable logistic regression analysis in the so far largest CH cohort reported in this context. The authors performed 3 analyses: 1) all patients (n=469) without imaging result, 2) all patients with imaging result (n=404), and 3) only patients with gland in situ (n=159). First, in all patients (thyroid dysgenesis and gland in situ), they show the LT4 dose cut-off level < 3.0 mcg/kg/d at age 12 months has 74% sensitivity and 83% specificity for transient CH. Second, they developed a 4-item risk score (without imaging results) to predict transient CH and successful weaning of LT4 beyond the age of 12 months.

These data are important in the context of the increasing incidence of transient CH. The risk score provides a simple but robust prediction to assess the likelihood of transient vs. permanent CH beyond the age of 12 months and will help counsel parents whether and at what age weaning off LT4 therapy might be safe for their child.

References: 1. Congenital Hypothyroidism: A 2020-2021 Consensus Guidelines Update-An ENDO-European Reference Network Initiative Endorsed by the European Society for Pediatric Endocrinology and the European Society for Endocrinology. van Trotsenburg P, Stoupa A, Léger J, Rohrer T, Peters C, Fugazzola L, Cassio A, Heinrichs C, Beauloye V, Pohlenz J, Rodien P, Coutant R, Szinnai G, Murray P, Bartés B, Luton D, Salerno M, de Sanctis L, Vigone M, Krude H, Persani L, Polak M. Thyroid. 2021 Mar;31(3):387–419. doi: 10.1089/thy.2020.0333. PMID: 33272083. 2. Early Determinants of Thyroid Function Outcomes in Children with Congenital Hypothyroidism and a Normally Located Thyroid Gland: A Regional Cohort Study. Saba C, Guilmin-Crepon S, Zénaty D, Martinerie L, Paulsen A, Simon D, Storey C, Dos Santos S, Haignere J, Mohamed D, Carel JC, Léger J. Thyroid. 2018 Aug;28(8):959–967. doi: 10.1089/thy.2018.0154. Epub 2018 Jul 30. PMID: 29968521.