Early adolescence assessment of eleven boys treated with continuous subcutaneous infusion (CSGI) of recombinant LH and FSH during infancy.

Introduction: We previously observed that continuous subcutaneous gonadotropin infusion (CSGI) in infants with congenital hypogonadotropic hypogonadism (CHH) can mimic minipuberty.

Objective: to describe the early adolescence outcome of boys treated during the first year of life.

Methods: In this retrospective cohort study, we describe 11 CHH boys aged 12 years [11.5-14.6] treated at the age of 4.5 months [2.0-11] with CSGI. To caompare we report testicular function of 12 untreated CHH boys aged 12 years [12-15.9].

Results: In response to CSGI, serum testosterone and inhibinB levels increased from 0.03 ng/mL [0-0.07] to 2.25 ng/mL [1.12-3.86] and from 73 [11-173] to 401 [185-727] pg/mL, respectively. Testicular volume increased from 0.50 mL [0.5-1] to 1.50 mL [0.7-3]. Between end of CSGI and early adolescence, testicular volume in the treated group decreased from 1.5 mL [0.7-3] to 1.05 ml [0.7-2.36] (p=0.024) and differed from that in untreated boys (0.3 mL [0.13-1.3]). Hormone levels were higher in the treated group : serum AMH and inhibin B levels in treated patients decreased from 1028 pmol/l [550-1750] and 356 [185-727] pg/mL at neonatal period to 331 pmol/l [85-479] and 68 pg/ml [19-239] respectively at early adolescence and differed from those in untreated patients (57.5 [30-169] and 8 pg/ml [<5-37] (p<0.001)).

Conclusion: We report the first long-term follow-up of CHH boys treated with CSGI in infancy. Our results shown that the CSGI treatment resulted in higher inhibin B, AMH levels and testicular volume at early adolescence age. Follow-up should be continued until the end of puberty to assess spermatogenesis.