Improving the diagnostic reliability of rapidly fluctuating plasma hormone levels by optimized multiple-sampling...

Area of Science:

• Endocrinology
• Clinical Chemistry
• Hormone Assays

Background:

• Plasma hormone levels, including testosterone, Follicle-Stimulating Hormone (FSH), and Luteinizing Hormone (LH), exhibit significant and rapid oscillations.
• Single random blood samples may not accurately reflect the true mean hormone concentration due to these fluctuations.

Purpose of the Study:

• To determine the optimal blood sampling strategy for accurately measuring oscillating hormones like testosterone, FSH, and LH.
• To assess the reliability of single versus multiple sampling methods for hormone level determination.

Main Methods:

• Computer analysis was employed to evaluate different sampling schedules.
• Investigated the reliability of single random samples versus multiple, equally-spaced samples.
• Considered practical constraints for sampling intervals and laboratory workload.

Main Results:

• A single random sample provides only a 68% chance of being within +/-20% of the true mean for testosterone, 54% for FSH, and 30% for LH.
• Computer analysis identified an optimal schedule of three equally-spaced samples (6-18 min intervals) for increased reliability.
• Pooling these three samples before radioimmunoassay analysis maintains accuracy without increasing laboratory workload.

Conclusions:

• For accurate assessment of rapidly oscillating hormones, multiple sampling is essential.
• An optimized protocol involves three equally-spaced samples, pooled for radioimmunoassay, balancing accuracy and laboratory efficiency.
• This approach enhances the reliability of hormone level measurements in clinical settings.