ESPE Abstracts

Background: With improvements in assays and an increasing need for non-invasive out-patient based investigations, there is a renewed interest in the use of urinary gonadotrophins (uGn) for assessing pubertal progress.

Objective and hypotheses: This study aims to establish the correlation between serum and urinary LH and FSH in patients with pubertal concerns.

Method: 36 boys and girls aged 14.9 years (range 7.8–17.3) and 9.5 years (4.3–18.4) respectively, who were undergoing an assessment of puberty had a non-timed spot urine sample on one occasion (n, 24) or consecutively (n, 12) for measurement of LH and FSH by chemiluminescent microparticle immunoassay. 13 of them (5M, 8F) were receiving GnRH-agonist (GnRH-a) treatment. In 24 cases (12M, 12F), matched serum gonadotrophins were also available. Urinary LH (uLH) and urinary FSH (uFSH) were corrected for creatinine excretion and compared to previously published reference data.

Results: A significant correlation was found between serum LH and uLH:uCr (ρ, 0.87; P<0.001) and serum FSH and uFSH:uCr (ρ, 0.91; P<0.001). In pubertal boys (n, 10) and girls (n, 8) with raised serum gonadtrophins, median uLH:uCr was 0.17 (0.1, 1.3) and uFSH:uCr 0.55 (0.1, 16.1), higher compared to pre-pubertal reference ranges (P=0.000, both for uLH and uFSH). In 13 boys and girls on GnRH-a, median uLH:uCr was 0.02 (0.01–0.08) and uFSH:uCr was 0.16 (0.04–0.32), similar to the pre-pubertal reference range (p uLH:uCr=0.39 and p uFSH:uCr=0.31). uGn of patients on GnRH-a showed a rapid decrease after treatment onset, while maintained pre-pubertal values when evaluated after the second injection, and consistent with clinical evidence of pubertal suppression.

Conclusion: uGn reflect serum gonadotrophin concentrations and may represent a useful non-invasive method of assessing puberty and monitoring effectiveness of puberty suppressive therapy.