ESPE Abstracts

Background: Central precocious puberty (CPP) is uncommon before the age of 4 and treatment with GnRH analogues have shown unequivocal benefits. CPP during or near mini puberty entails differential clinical and biochemical features in the diagnosis and leads to longer treatment and follow-up. There are very limited studies with long-term outcomes about CPP girls exclusively < 4 years of age regarding growth, menarche, and adult height after GnRHa withdrawal.

Objective: We describe a long-term case series of girls diagnosed with CPP who started GnRH analogue treatment before the age of 4 years and reached adult height.

Methods: Retrospective descriptive study that included 8 girls with CPP diagnosed before the chronological age (CA) of 4 years that reached adult height. Inclusion criteria were progressive breast growth, advanced bone age, vulvar signs of estrogenic stimulation, LH after GnRH stimulation test >20 UI/L. All girls received Triptorelin one-month formulation and were followed-up in our center. Patients with neurogenic causes were excluded, except for hypothalamic hamartomas. Data are expressed in median (range).

Results: 6 out of 8 girls had idiopathic CPP and 2 presented hypothalamic hamartoma. The CA of treatment onset was 2.5 (0. 7-3.3) years and the difference between bone age (BA-CA) was 1.2 (0.3-3.3) years. 7 girls presented thelarche and pubarche at diagnosis and 2 of them had presented vaginal bleeding. At diagnosis, height was 3.2 (1.5 - 3.9) SDS and height for bone age (H-BA) was -0.1 (-2.4 - 1.3) SDS. GnRHa was discontinued after 8 (7.4-10.2) years. At this time, CA, BA-CA and H-BA were 10.6 (10.1 - 11.1) years, 1.3 (-0.1-2.2) years and 0.1 (-0.9-1.1) SDS, respectively. Growth velocity was 7.2 (4.5-9.6) cm/year after 1 year of GnRHa cessation. Adult height was 161 (154-169) cm [0.0 (-1 – 1.4) SDS], in accordance with their mid-parental height [0.3 (-0.5 – 1.5) SDS]. Menarche occurs at a median CA of 11.6 years, within 1.2 years after therapy suspension The growth after discontinuation treatment to achieve AH was 12.9 (8.2-21) cm. The strongest correlation for AH was H-BA-SDS at the end of treatment (r= 0.93, p < 0.01).

Conclusion: The outcome for adult height in patients with central precocious puberty diagnosed before the age of 4 was optimal. Long-term GnRHa treatment prevented progression of bone age, allowing girls to reach adult height according to their mid-parental height range. The most important predictor of adult height was H-BA-SDS at the end of treatment.