Triptorelin-Stimulated LH Concentrations Can Help Diagnosis Central Precocious Puberty

A new study suggests measurements of triptorelin-stimulated luteinizing hormone (LH) concentrations provided high diagnostic accuracy for diagnosis of central precocious puberty in girls when compared to the gold standard GnRH test.

A case-control clinical study using data from 60 girls receiving care at the Department of Endocrinology at the Mother and Child Health Care Institute of Serbia, results of the study indicate triptorelin-stimulated LH concentrations were significantly higher in girls with central precocious puberty, with the highest diagnostic accuracy for central precocious puberty occurring at 180 minutes with a cut-off value of 3.4 IU/L or greater.

“The present study identified a high diagnostic accuracy of LH concentrations after triptorelin injection when diagnosing CPP in girls with premature thelarche compared to the gold standard GnRH test. This suggests that triptorelin-stimulated LH concentrations can be used as a reliable alternative for evaluation of the HPG axis when intravenous GnRH is unavailable,” wrote investigators.

Led by a team based out of the University of Belgrade, the current study was conducted with the intent of assessing the diagnostic accuracy of triptorelin-stimulated luteinizing hormone concentrations for diagnosis of central precocious puberty among girls presenting with premature thelarche compared to GnRH test. With this in mind, investigators designed the study as a prospective, case-control, clinical study using data from 60 girls with premature thelarche who underwent stimulation wit subcutaneous triptorelin injection and intravenous GnRH.

All girls included in the study received care between November 2017-Septemeber 2020 and were referred to the endocrinology clinic for evaluation of premature thelarche. Of the 60 girls included in the study, 32 were included in the central precocious puberty group and 28 had isolated premature thelarche. During the stimulation test with triptorelin, both LH and follicle-stimulating hormone (FSH) 0, 30, 60, 90, 120, and 180 minutes after the injection.

During GnRH test, LH and FSH were measured at 0, 30, 45, and 60 minutes. For the purpose of analysis, girls with peak GnRH-stimulated LH concentrations of 5.0 IU/L or greater were classified as having central precocious puberty. Investigators assessed area under the curve (AUC) for triptorelin-stimulated LH concentrations using the receiver operating characteristic (ROC).

Upon analysis, results indicated triptorelin-stimulated LH concentrations were significantly greater among girls with central precocious puberty on GnRH tests (53.3%). Results also indicated LH concentrations peak at 180 minutes after the triptorelin injection. Further analysis suggested the highest diagnostic accuracy for central precocious puberty at 180 minutes was at a LH concentration of 3.4 IU/L or greater (AUC=0.973; sensitivity, 96.9%; specificity, 89.3%). Investigators noted the 24-hour estradiol concentration did not improve the predictive model.

“This strategy provides high diagnostic accuracy, short hospital stays, and is less invasive compared to the GnRH gold standard model and previously proposed test protocols using triptorelin,” investigators added.

Investigators pointed out clinicians should consider the limitations within their study before overinterpretation of their findings. Specifically, investigators underlined the fact that all girls were Caucasian and only included girls with premature thelarche who were otherwise healthy. Although investigators point out GnRH should remain the gold standard for diagnosis of central precocious puberty, results of their study highlight the potential of another diagnostic modality.

“We must always have in mind that not everyone in the world has access to the same level of medical care, including the medications available for both diagnostic and therapeutic purposes. That is exactly the case with the intravenous GnRH preparation that is often unavailable in countries such as India, Brazil, Thailand, or Serbia. Also, with the widespread drug shortages seen during the current COVID-19 crisis and the global disruption of supply chains, the availability of the intravenous GnRH preparation may become affected even in wealthier countries worldwide,” investigators added.

This study, “Triptorelin stimulated luteinizing hormone concentrations for diagnosing central precocious puberty: study of diagnostic accuracy,” was published in Endocrine.