Factors Affecting Thyroid Volume in Children Aged 4 to 18 Years

Ultrasound measurement of thyroid volume is not routinely performed in children without suspected thyroid disorders. However, pediatricians must be aware of the normal thyroid volume values in children in order to recognize and treat thyroid disorders in children on time. Therefore, this study aimed to explore factors that influence thyroid volume in children aged 4 to 18 years and to provide descriptive data on thyroid volume across this age range.

This was a prospective, non-interventional cross-sectional study conducted on a population of children aged 4 to 18 years without confirmed thyroid disorders. We used validated formulas for calculating thyroid volume that integrate the linear dimensions of this organ, such as length, width, and depth, as well as the appropriate correction factor. The Spearman or Pearson correlation coefficient was calculated to assess the relationship between total thyroid volume and various continuous variables, while multiple linear regression analysis was used to evaluate the effect of potential predictors on the total thyroid volume.

The study included 100 children, predominantly girls (75.0%). Significant positive correlations with thyroid volume were found for age, height, weight, body mass index (BMI), body surface area, serum creatinine, birthweight, and number of comorbidities, while calcitonin was negatively correlated with children's thyroid volume. We identified age, BMI, and serum creatinine as significant independent positive predictors of thyroid volume in children.

Age, BMI, and serum creatinine emerged as significant independent positive predictors of thyroid volume and should be considered when interpreting pediatric thyroid ultrasound measurements.