Endocrine Abstracts

Congenital hypogonadotropic hypogonadism is a rare reproductive disorder characterised by isolated deficiency in the secretion or action of gonadotropin-releasing hormone (GnRH). Diminished GnRH activity in the immediate postnatal months, a period known as minipuberty, has severe consequences on the ontogenesis of male reproductive tract. Affected infant boys may present with micropenis and cryptorchidism. Rarely, adolescents with CHH present with delayed puberty in association with cryptorchidism. While the use of gonadotropins to treat CHH-associated cryptorchidism in infancy is increasingly recognised as a safe and effective therapy, there is scarce data on its utility in adolescents or young adults. Indeed, if such treatment is shown to be efficacious beyond childhood, patients could potentially be spared from surgical orchidopexy. We report two young men who had successful hormonal induction of testicular descent. The first case was a 19-year-old male referred for pubertal failure. He had childhood history of micropenis as well as surgery for undescended testes at 5 years old. Testes were, however, not palpable during examination. Penile length was 4 cm, and there was no sign of any secondary sexual characteristics. Ultrasound scan demonstrated undescended testes (Right: 0.6×0.7×0.8 cm, Left: 0.7×0.8×1.3 cm) in the inguinal canal bilaterally. Kallmann syndrome was subsequently diagnosed based on anosmia and hypogonadotropic hypogonadism (FSH 0.4 U/l, LH <0.1 U/l, testosterone 0.78 nmol/l). Sequential gonadotropin therapy was started with hMG (75 IU daily for 4 weeks) followed by combined hMG and hCG therapy, which were up-titrated to 150 IU 3×/week and 1,500 IU 3×/week respectively. Ultrasound repeated 12 months later showed descent of testes into scrotum bilaterally (Right: 0.9×1.1×1.7 cm, Left: 1.0×1.4×2.4 cm). The second case was a young man who was referred at age 22 years for undervirilisation. Both testes were non-palpable. Biochemistry showed FSH 2.3 U/l, LH 0.8 U/l and testosterone 1.4 nmol/l. Ultrasound confirmed bilateral undescended testes in the upper part of the groin area, on either side of the base of penis (Right: 1.4×1.0×0.8 cm, Left: 1.5×1.1×0.7 cm). Patient was first given FSH monotherapy (75 IU, 3×/week) for 4 months, after which hCG was added and up-titrated to 1,500 IU 2×/week. Ultrasound was repeated 8 months later to reassess testicular position, which showed that the descent of testes into the mid-scrotum, along with a threefold increase in the testicular volume. In concordance, serum inhibin B level rose from baseline 21 pg/ml to 61 pg/ml.