Related Experiment Videos
[Prevalence of deficiency of thyroxine-binding globulin (TBG)]
1Unidad de Recién Nacidos y Cuidado Intensivo Neonatal, Hospital Militar Gorgas, Ancón, Panamá.
Insights
Congenital hypothyroidism screening in newborns identified a higher prevalence of thyroid-binding globulin deficiency, particularly in males. This finding suggests a need for targeted screening for this genetic condition.
Area of Science:
- Endocrinology
- Neonatal screening
- Genetics
Context:
- Newborn screening programs aim to detect congenital disorders early.
- Thyroid hormone levels are crucial for infant development.
- Thyroid-binding globulin (TBG) deficiency can affect thyroid hormone measurements.
Purpose:
- To screen newborns for congenital hypothyroidism.
- To investigate the prevalence of thyroid-binding globulin (TBG) deficiency in newborns with low thyroxine levels.
Summary:
- A 3-year study screened 1632 newborns for congenital hypothyroidism using serum thyroxine (T4) levels.
- Three male newborns (1.8/1000 live births) were diagnosed with familial TBG deficiency, exhibiting significantly lower cord T4 levels.
- The study observed a TBG deficiency prevalence approximately 10 times higher than previously reported.
Impact:
- Highlights a potentially underestimated prevalence of TBG deficiency in the male newborn population.
- Suggests the need for considering TBG deficiency in the differential diagnosis of hypothyroidism in male infants.
- Informs future newborn screening protocols and genetic counseling strategies.
Abstract:
During 3 years 1632 newborns from Gorgas Army hospital had their cord blood screened for congenital hypothyroidism by determining serum thyroxine levels (T4). Fifty-five had serum levels below 7 mcg/dl and 80% of them went into a confirmatory evaluation for hypothyroidism. Three of those (1.8/1000 live birth) had a familiar deficiency of thyroid binding globulin (TBG). All of them were male newborns born at 38 weeks of gestation. The average T4 from the umbilical cord was 2.4 +/- 1.3 mcg/dl. This value was significantly lower than the values from those with an initial T4 below 7 mcg/dl who did not have TBG deficiency. The prevalence of TBG deficiency in this study was about 10 times higher than the prevalence reported by other authors for both the general population and the male population.