Endocrine Abstracts

Background: Hypogonadotropic hypogonadism in apubertal males is commonly due to constitutional delay; permanent gonadotropin deficiency becomes more likely with older age at presentation, cryptorchidism and non-reproductive defect, e.g. anosmia. All forms of testosterone induce pubertal development, though short-acting IM preparations are associated with extraphysiological excursions of serum testosterone and are increasingly unavailable. Long-acting testosterone undecanoate IM (TU) is widely-used in men due to superior pharmacokinetics, but data relating to induction of puberty are limited. From 2007, patient preference led us to adopt it for pubertal-induction in hypogonadotropic apubertal males aged 17+ years.

Aims: To audit our experience of IM TU for pubertal induction, focusing on i) patient acceptability/tolerability, ii) maintenance of physiological haematocrit and testosterone levels, and iii) clinical progression through puberty.

Patients and methods: n=7 patients presenting 2007–2011; 6/7 assumed to have permanent hypogonadism due to age (mean 37.6 years; range 17.3–57.8) and/or clinical features. Longitudinal data recorded for height, BMI, pubertal staging, pre-injection serum testosterone, haemoglobin and haematocrit. TU administered ~3–4-monthly, guided by lab results and clinical assessment.

Results: Mean treatment duration over the first 3–5 TU injections was 0.91 years (range 0.51–1.04); mean injection interval 13.24 weeks (range 7–18). There were no supraphysiologic excursions of serum testosterone, haemoglobin or, haematocrit. No patient experienced any adverse physical or psychological effects, except for male-pattern baldness (n=1). All completed pubertal development around a year from treatment-initiation. After 3 years, two older men (age 50.8 and 57.8 years) exhibited major improvement in bone density (23.5 and 40% at L-spine; 26.6 and 46% at hip, respectively).

Conclusions: All seven men completed pubertal development without adverse effects and with excellent adherence to replacement therapy. TU is a safe and effective treatment for the initiation of puberty in males aged 17+ years. Anxieties in respect of inducing puberty in late-presenting apubertal men are largely unfounded.