Cognitive outcome of 458 children over 25 years of neonatal screening for congenital hypothyroidism

Abstract Objectives: To describe the neurocognitive profile of 458 children with congenital hypothyroidism detected by neonatal screening, followed under the same treatment protocol over 25 years. To correlate estimated full-scale IQ (FSIQ) scores with age at the start of treatment, disease severity, and maternal education. Methods: Observational, analytical, retrospective, and longitudinal cohort study, that evaluated children detected between 1991 and 2014, who underwent at least one psychometric assessment (WPPSI- R and/or WISC-III). Estimated FSIQ scores are described and correlated with prognosis determinants. Results: Median T4 at diagnosis was 2.8 µg/dL (0.0-16.5), the median age at the start of treatment was 18.5 days (3-309). Maternal education (n = 445): 2.7% of illiteracy, 59.8% with basic education. Estimated FSIQ scores were 88.0 (±11.8) in WPPSI-R (age 5.6 ± 0.5 years) and 84.1 (±13.0) in WISC-III (age 9.1 ± 1.4 years). The intellectual deficit was identified in 11.6%. Correlation between age at the start of treatment and estimated FSIQ was found only in the WPPSI-R test (p = 0.02). Initial T4 and maternal education significantly correlated with estimated FSIQ scores in both tests, with the latter being the most important determining factor. Conclusions: In this large cohort of mainly low socioeconomic status children, most children achieved normal cognitive levels; however, a significant percentage presented with below-average estimated FSIQ scores and intellectual deficits. Maternal education was the main determining factor in cognitive level followed by hypothyroidism severity.

Hipotireoidismo neonatal transitório causado pelo uso de amiodarona durante a gestação: relato de dois casos e revisão da literatura / Transient neonatal hypothyroidism due to amiodarone administration during pregnancy: two cases report and review of literature

INTRODUÇÃO: A amiodarona (AMD) é uma droga antiarrítmica que contém 37 por cento de iodo. A AMD pode alcançar o feto por via transplacentária e causar hipotireoidismo congênito (HC) ou transitório (HCT). Relatamos dois casos de HCT em virtude de exposição gestacional à AMD, detectados pelo programa de triagem neonatal para HC no Estado do Paraná, Brasil. CASO CLÍNICO 1 (C1): TSH neonatal 78,2 mU/L (normal < 15 mU/L). A AMD foi utilizada durante toda a gestação em virtude de arritmia materna. As dosagens séricas iniciais confirmaram o HC; e na primeira consulta [aos 14 dias de vida (dv)], foi iniciada levotiroxina (L-T4), 50 µg/dia. CASO CLÍNICO 2 (C2): TSH neonatal 134 mU/L. A AMD foi utilizada no último trimestre da gestação em virtude de arritmia materna. As dosagens séricas iniciais confirmaram o HC; aos 13 dv, foi iniciada L-T4 50 µg/dia. ACOMPANHAMENTO: TSH e T4 estavam normais aos 51 dv (C1) e aos 36 dv (C2) sendo então gradativamente reduzida a dose da medicação e suspensa aos 16 meses (C1) e aos dez meses (C2). As pacientes foram acompanhadas até 22 meses (C1) e 16 meses (C2) com testes de função tireoidiana normais. O crescimento e o desenvolvimento neuropsicomotor (DNPM), avaliados pelo teste CAT/CLAMS, eram normais. CONCLUSÃO: As avaliações da função tireoidiana e do DNPM são necessários quando a AMD é utilizada na gestação. O tratamento do HCT deve ser instituído tão logo o diagnóstico seja realizado.

INTRODUCTION: Amiodarone (AMD) is an antiarrhythmic agent which contains 37 percent of iodine. It can reach the fetus by transplacental passage and induce transient congenital hypothyroidism (TCH). We report two cases of TCH caused by gestational exposure to AMD, detected by the Newborn Screening Program for Congenital Hypothyroidism of the State of Paraná - Brazil. CLINICAL CASE 1 (C1): Neonatal TSH value was 78,2mU/L (normal < 15 mU/L). AMD had been given to the mother during pregnancy to treat maternal arrhythmia. The screening results were confirmed by serum thyroid function tests. Levothyroxin (L-T4) (50µg/day) was started on the first visit, on the 14th day of life (dl). CLINICAL CASE 2 (C2): Neonatal TSH value was 134,0 mU/L. AMD had been given to the mother in the third trimester of pregnancy to treat maternal arrhythmia. The screening results were confirmed by serum thyroid function tests: L-T4 (50µg/day) was started on the first visit, with 13 dl. FOLLOW-UP: TSH and T4 normalized on 51 dl (C1) and 36 dl (C2); L-T4 could be diminished gradually and stopped within 16 months (C1) and 10 months (C2). They were followed-up until 22 months (C1) and 16 months (C2) with normal thyroid function tests. Their growth and mental development, evaluated by the Cognitive Adaptive Test/Clinical Linguistic & Auditory Milestone Scale (CAT/CLAMS test), were normal. CONCLUSION: Evaluation of thyroid function and mental development should be performed if AMD is used during pregnancy. Treatment of TCH must be started as soon as the diagnosis is made.