Ultrasonographic Assessment of the Thymus Among Neonates Admitted in a Special Newborn Care Unit of a Medical College Hospital in Eastern India

TL;DR

This study used ultrasound to assess thymus size in neonates in Eastern India and found that birth weight is a key factor influencing thymic development.

Contribution

The study provides new regional data on neonatal thymic ultrasonography and identifies birth weight as a significant predictor of thymic dimensions.

Findings

Thymic dimensions showed significant positive correlations with birth weight.

Birth weight was a significant predictor of the thymic index, explaining 21.2% of the variance.

Thymic measurements did not significantly differ between male and female neonates.

Abstract

Introduction: The thymus is essential for the maturation of T-lymphocytes, crucial for adaptive immunity. In neonates, thymic development is influenced by factors such as gestational age, birth weight, birth length, etc. Ultrasonography offers a non-invasive method to assess thymic size and morphology. However, there is limited research on thymic ultrasonography among neonates in Eastern India. This study aimed to investigate the ultra-sonographic characteristics of the thymus in neonates admitted to a Special Neonatal Care Unit (SNCU) in Eastern India and its correlation with certain clinical and anthropometric variables.

Materials and methods: Conducted from May to July 2024, this cross-sectional observational study involved 80 neonates admitted to the SNCU at the College of Medicine & Sagore Dutta Hospital. Thymic ultrasonography, using an Esaote MylabX7 ultrasound machine with a 3-11 MHz linear probe (Esaote, Genoa, Italy), measured thymic length, width, anteroposterior (AP) dimension, sagittal area, and thymic index. Clinical data, including gestational age, birth weight, birth length, and antibiotics received, were collected from medical records. Pearson's correlation coefficient and linear regression analysis were used to examine correlations and predictors of thymic dimensions.

Results: The cohort consisted of 45 boys (56%) and 35 girls (44%). The average birth weight was 2,626 grams for boys and 2,639 grams for girls. The median gestation period was 38 weeks for both groups. Thymic measurements did not significantly differ by gender. Correlation analysis revealed significant relationships between thymic dimensions and neonatal anthropometric measurements. Birth weight showed a strong positive correlation with thymic length (r = 0.486) and width (r = 0.233). Linear regression identified birth weight as a significant predictor of the thymic index (p < 0.001), explaining 21.2% of the variance.

Conclusion: This study provides insights into the factors associated with thymic size in neonates, highlighting the critical role of birth weight in thymic development. Future research should explore additional variables influencing thymic size and consider larger sample sizes to enhance model explanatory power and its potential role in immunity.

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