Triptorelin depot stimulation test for central precocious puberty.

Background: Acute gonadotropin responses following depot leuprolide acetate injection are useful for monitoring therapeutic efficacy in central precocious puberty. Similar monitoring of therapy in patients treated with another widely used GnRH agonist, depot triptorelin, has not yet been reported.

Objective: The objective of this study was to test the use of gonadotropin levels after therapeutic injections of depot triptorelin for evaluating efficacy of therapy.

Patients And Methods: Thirty-two patients (29 girls and three boys) were treated with triptorelin depot, 3.75 mg per vial, between 2006 and 2010. Treatment was initiated at 8.27±1.76 years (range, 4.6-11.6 years). Blood was drawn before and at variable times between 30 min and 2 h after injections. Clinical tests were retrospectively collected.

Results: After the first injection, the 60-min mean luteinizing hormone (LH) level was 21.6.1±18.0 IU/L and the follicle-stimulating hormone (FSH) was 13.5±3.6 IU/L. After subsequent injections, for those who showed clinical suppression, the standard deviations above the mean were 3.6 IU/L for FSH and 2.1 IU/L for LH. The LH levels of two patients who did not suppress sufficiently were at these limits or higher.

Conclusions: Sixty-minute postinjection depot triptorelin levels of LH can be successfully used to evaluate the efficacy of treatment with this agent. Limits for suppressed levels have been determined.