A single blood sample for stimulated LH assayed by ICMA is useful for monitoring the treatment efficacy of triptorelin depot in girls

Abstract

Background: There is still no consensus on the optimal monitoring method to evaluate the hypothalamic-pituitary-gonadal axis (HPGA) inhibition. Methods: There were 124 girls treated with triptorelin depot due to puberty disorders, including 77 central precocious puberty and 47 early puberty. After treatment, triptorelin stimulation tests were performed, and blood samples were collected at 0, 20, 40 and 60 min. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured by immunochemiluminometric assay (ICMA). Results: Peak LH (PLH), peak FSH and estradiol in 124 girls were significantly decreased after treatment, while 2 cases had inadequate treatment efficacy. Areas under the receiver operating characteristic curves (AUC) of PLH and peak FSH after stimulation for the diagnosis of HPGA suppression were 0.984 and 0.121. When the cut-off value of PLH was ≤ 2.25 IU/L, the sensitivity was 96.7% and specificity was 100.0%. There was no difference in AUC between PLH and a single LH at 20, 40, or 60 min (p > 0.05). When LH were ≤ 2.34 IU/L, ≤ 2.21 IU/L and ≤ 2.00 IU/L at 20, 40 and 60 min, respectively, the sensitivity were 99.1%, 96.7% and 98.4%, and the specificity were all 100.0%. The correlation coefficients between PLH and LH at 20, 40 or 60 min were 0.947, 0.975 and 0.961. Conclusion: A single blood sample for stimulated LH at 20 min, 40 min, or 60 min assayed by ICMA during triptorelin stimulation test is useful for monitoring the treatment efficacy of triptorelin depot in girls with puberty disorders.

Keywords:

• Luteinizing hormone
• triptorelin
• GnRH stimulation test
• treatment efficacy
• girls
• precocious puberty
• triptorelin depot

Author contributions

Ma Y and Xu Z conceived the idea. Ma Y, Zhou Y and Jia R collected data. Zhou Y and Jia R carried out the data check and statistics. Zhou Y drafted the manuscript. Ma Y and Zhou Y critically revised and edited the manuscript. Jia R revised the manuscript. Kong F and Xu Z participated in the revision of the paper. Chen M and Ren F participated in the collection and quality control of laboratory data. All authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This project was supported by Top Talent Support Program for young and middle-aged people of Wuxi Health Committee [No. HB2020038]; the Maternal and Child Health Research Project of Jiangsu in China [No. F202117]; the Maternal and Child Health Research Project of Wuxi in China [No. FYKY201804]; and the Excellent Program for Overseas Students of Wuxi City in 2018 [No. 23], China.