Endocrine Abstracts

A 17-year-old male was referred to our hospital with lack of secondary sex characteristics. His voice didn’t break and he lacked of pubes and hircus. His bilateral testicular volume was small and his sense of smell was normal. There was no varicocele or pituitary adenoma. His chromosomal study showed no aberrations. Serum levels of LH, FSH, total testosterone and free testosterone were 1.05 mIU/ml, 1.68 mIU/ml, 0.26 ng/ml and <0.6 pg/ml respectively. A repeated GnRH test revealed sluggish, but significant response of LH and FSH. In contrast, human chorionic gonadotropin (hCG) stimulation test showed normal response of testosterone. With these results, he was diagnosed as idiopathic hypogonadotropic hypogonadism (IHH).

Although there is no consensus in the first-line therapy for IHH, there are some case reports indicating that IHH patients attained remission after r-hFSH and hCG replacement. In our case, response of LH to GnRH might suggest effectiveness of this therapy.

However, because he disliked frequent injections, he chose testosterone replacement therapy instead of r-hFSH and hCG replacement. After 2 months, his body hair gradually grew and his voice changed. After 13 months, in anticipation of recovery of his own hormonal secretory capacity, r-hFSH and hCG replacement therapy was introduced instead of testosterone therapy. At 6 months after initiation of the treatment, his serum level of total testosterone reached 7.33 ng/ml, then, he discontinued replacement therapy. Finally, his serum levels of LH, FSH and testosterone had been kept within normal range and he holed sexual desire and activity.

We experienced a case in whom r-hFSH and hCG replacement therapy successfully normalized pulsatile gonadotropin secretion, serum testosterone level and sexual function. Because IHH has several variations, it is important to carefully choose a therapy depending on each case.