Commentary on "Single random measurement of urinary gonadotropin concentration for screening and monitoring girls with central precocious puberty"

Article information

Ann Pediatr Endocrinol Metab. 2021;26(3):136-137

Publication date (electronic) : 2021 September 30

doi : https://doi.org/10.6065/apem.2120104edi01

Ahreum Kwon

Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea

Address for correspondence: Ahreum Kwon Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea Email: armea@yuhs.ac

This article [1] evaluates whether a single random measurement of urinary luteinizing hormone (LH) could diagnose the central precocious puberty (CPP) and monitor the effectiveness of the gonadotropin-releasing hormone (GnRH) agonist treatment. Because CPP is caused by premature activation of the hypothalamic-pituitary-gonadal axis, GnRH stimulation test is considered the gold standard for CPP diagnosis. However, the GnRH stimulation test is invasive, expensive, and relatively takes a long time of more than 2 hours. Therefore, many other simple tests including basal serum LH level, LH/follicle-stimulating hormone ratio, gonadotropin concentrations in the first morning-voided urine and in 24-hour urine, have been proposed to replace the GnRH stimulation test [2]. However, basal serum gonadotropin levels have diurnal variation and lower sensitivity and specificity. In addition, although measuring urinary concentrations of gonadotropins is noninvasive, convenient, and easy, there is a limit for testing the first-voided urine in the morning or collecting 24-hour urine in an outpatient clinic. This recent study shows that when urinary gonadotropin concentrations are measured, it is sufficient to measure random urine, not first-voided urine or 24-hour collecting urine. Especially because randomly measured urinary concentrations of gonadotropins significantly decreases during GnRH agonist treatment, it might be useful to monitor during GnRH agonist treatment in CPP girls [1,3].

However, even though urinary gonadotropin concentrations sharply increase in puberty [4], it periodically shows every other day in fluctuating patterns [5]. In addition, the number of subjects in this study remains small, raising questions about the statistical significance of the data. Therefore, further large-scale prospective studies are needed to confirm the usefulness and value of the randomly measured urinary concentrations of gonadotropins. Nevertheless, based on the results of the present study [1], it is worth replacing serum gonadotropin concentration test to monitor the treatment effect, which will alleviate the pain of many CPP girls undergoing GnRH agonist treatment.