Mapping the serum testosterone landscape in boys aged 1-14 years: A population-based study.

Area of Science:

• Pediatric Endocrinology
• Andrology
• Biostatistics

Background:

• Testosterone is critical for male development, but age-specific reference data is lacking.
• This data gap hinders the diagnosis of conditions like delayed puberty and disorders of sex development.

Purpose of the Study:

• To establish age-specific serum testosterone reference values for boys aged 1-14 years.
• To generate centile curves for predicting testosterone levels based on age.

Main Methods:

• Serum testosterone levels were measured in 1398 boys aged 1-14 years.
• Chemiluminescent microparticle immunoassay was utilized for testosterone measurement.
• Generalized Additive Models for Location, Scale, and Shape (GAMLSS) framework generated centile curves.

Main Results:

• Serum testosterone levels showed a significant age-dependent increase (correlation coefficient: 0.6; p ≤ 0.001).
• Testosterone levels remained low with minimal variability until puberty onset, followed by a steep rise.
• Puberty significantly widened the inter-percentile range, indicating high individual variability.

Conclusions:

• Established centile curves and reference values address a critical literature gap in pediatric endocrinology.
• These tools will aid in the clinical differentiation of physiological variations from pathological conditions.
• Findings highlight the importance of personalized assessment due to individual variability in testosterone levels and pubertal timing.