Utility of salivary enzyme immunoassays for measuring estradiol and testosterone in adolescents: a pilot study.

Aim: We investigated the utility of enzyme immunoassay kits for measuring low levels of salivary estradiol and testosterone in adolescents and objectively assessed prevalence of blood contamination.
Methods: Endocrine patients provided plasma and saliva for estradiol (females) or testosterone (males) assay. Saliva samples were also tested with a blood contamination kit.
Results: Picomolar levels of salivary estradiol in females failed to show any significant correlation with plasma values (r=0.20, p=0.37). The nanomolar levels of salivary testosterone in males showed a strong correlation (r=0.78, p<0.001). A significant number of saliva samples had blood contamination. After exclusion, correlations remained non-significant for estradiol, but strengthened for testosterone (r=0.88, p<0.001).
Conclusion: The salivary estradiol enzyme immunoassay is not clinically informative at low levels. Users should interpret clinical saliva with caution due to potential blood contamination. Our data supports the utility of the salivary testosterone enzyme immunoassay for monitoring adolescent boys on hormone developmental therapy.