Related Experiment Videos
Neuropsychological development in a child with early-treated congenital hypothyroidism as compared with her
S Bargagna1, L Chiovato, D Dinetti
1Stella Maris Scientific Institute, University of Pisa, Italy.
Insights
Early treatment for congenital hypothyroidism (CH) is crucial. Even with prompt intervention, CH may cause subtle, temporary delays in cognitive and motor skills compared to unaffected twins.
Area of Science:
- Pediatrics
- Endocrinology
- Neurodevelopmental Pediatrics
Background:
- Congenital hypothyroidism (CH) screening prevents severe neurodevelopmental deficits.
- The long-term impact of early-treated CH on intelligence and motor skills requires further investigation.
Purpose of the Study:
- To assess the neuropsychological outcomes in genetically identical twins, where one twin had CH and the other did not.
- To determine if early L-Thyroxine therapy normalizes cognitive and motor development in CH patients.
Main Methods:
- Case study of genetically identical twins, one with CH due to thyroid agenesis.
- Parallel neuropsychological evaluations from 3 months to 8 years of age.
- L-Thyroxine treatment initiated at 27 days of age.
Main Results:
- The CH twin exhibited slight, transient delays in motor and language development compared to her sibling.
- While IQ scores were within the normal range, the CH twin consistently scored lower than her unaffected twin until age 7.
- School performance was comparable to peers, but deficits were noted in specific areas compared to her twin.
Conclusions:
- In utero and neonatal hypothyroidism negatively impacts neuropsychological development, even with early treatment.
- Identical twins raised in the same environment highlight the detrimental effects of untreated hypothyroidism.
- Emphasizes the critical importance of early diagnosis and prompt treatment initiation for neonatal CH.
Objective:
Neonatal screening for congenital hypothyroidism (CH) prevents the serious neuropsychological features of CH, but the question remains whether intelligence and motor skills of CH children treated early are completely normal.
Design:
In this report we describe the rare case of two genetically identical twins, only one of whom was affected by CH due to thyroid agenesis. L-Thyroxine (9 microg/kg body weight/day) therapy was initiated at 27 days of age and was adequate throughout the follow-up.
Methods:
Neuropsychological evaluation was performed on the twins in parallel from 3 months to 8 years of age.
Results:
The CH twin (NB) did not show major neuromotor impairments but, compared with the unaffected twin (EB), she had a slight delay in postural/motor achievements and in language development that completely disappeared at 8 years of age. On standardised tests of intelligence, NB was indistinguishable from control children but, compared with her twin, she had lower IQ scores in most testing occasions up to 7 years of age (NB = 108 vs EB = 115). School achievements of NB did not significantly differ from those of her classmates but, compared with her twin, she scored worse in writing, mechanical reading, verbal memory, and possibly in arithmetic.
Conclusions:
Because the twins were genetically and phenotypically identical, were raised in the same environment, and received a similar education, it is concluded that hypothyroidism in utero and in the first neonatal month was responsible for the lower neuropsychological achievements of the CH twin. While foetal hypothyroidism is at present unavoidable, earlier diagnosis and initiation of treatment in neonates with CH are important and highly recommended.