Effect of short-term GnRH pulse therapy on pituitary-testicular function in adolescent male patients with congenital hypogonadotropic hypogonadism

Abstract

Objective·To investigate the effect of short-term gonadotropin-releasing hormone (GnRH) pulse therapy on pituitary and testicular function in the adolescent male patients with congenital hypogonadotropic hypogonadism (CHH).Methods·A retrospective study was conducted on 20 adolescent male patients with CHH who received GnRH pulse therapy from January 2016 to June 2021, and their clinical data were collected. They were treated with subcutaneous continuous pulsed administration of gonadorelin by the pump for 1 week (20 cases), of which 5 cases were treated for 3 months. The dose was 8‒10 μg per pulse, and the pulse interval was 90 min. The levels of luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone were measured before GnRH pulse therapy at 1 week, 1 month and 3 months after treatment. After 3 months of treatment, the testicular volume was measured. All 20 patients with CHH underwent whole exome sequencing.Results·The age of 20 CHH patients was 14.35 (14.08, 15.31) years old. The clinical manifestations were infantile testis (20/20) and micropenis (20/20), followed by obesity (12/20), dysosmia (9/20), insulin resistance (4/20), cryptorchidism (4/20), and short stature (3/20). The patients' height was 161.79 (154.90, 173.25) cm, body mass index was 23.80 (20.51, 27.46) kg/m2, and testicular volume was 0.91 (0.55, 1.25) mL. Inhibin B was 39.67 (11.29, 64.97) pg/mL; the base values of LH, FSH and testosterone before therapy were 0.20 (0.10, 0.30) IU/L, 0.87 (0.23, 0.89) IU/L, and 0.92 (0.38, 1.49) nmol/L, respectively. After 1 week of continuous GnRH pulse therapy, the base and peak values of LH and FSH and the peak value of testosterone in the 20 patients significantly increased (all P<0.05). In the 5 patients treated for 3 months, the base values and peak values of LH and FSH gradually increased with the prolongation of treatment time. After 3 months of treatment, the base values and peak values of LH and FSH, and the peak value of testosterone were significantly higher than those before treatment (all P<0.05), and the testicular volume was also significantly increased (P=0.004). Gene mutations were detected in only 14 of 20 patients, including fibroblast growth factor receptor 1 (FGFR1) mutations in 7 cases, anosmin 1 (ANOS1) mutations in 4 cases, prokineticin receptor 2 (PROKR2) mutations in 2 cases, and a prokineticin 2 (PROK2) mutation in 1 case. There was no significant difference of the effect of GnRH pulse therapy for 1 week on pituitary-testicular function between the patients with FGFR1 mutations and ANOS1 mutations.Conclusion·The continuous GnRH pulse therapy for 1 week can make pituitary-testicular function respond in adolescent male CHH patients; the treatment for 3 months helps to induce the secondary sexual characteristics of puberty.

Keywords

• hypogonadotropic hypogonadism
• gonadotropin-releasing hormone (gnrh)
• pulse therapy
• adolescent