Endocrine Abstracts

JOINT1462

Background: CDGP is one of the commonest reasons for referral to a pediatric endocrinologist. Boys with CDGP are shorter than their peers and pubertal onset is delayed. The differential diagnosis between CDGP and hypogonadotropic hypogonadism can be challenging. Although it is considered a self-limiting condition, boys with CDGP may present psychosocial burden and need treatment with testosterone to induce puberty, accelerate growth and improve quality of life. Transdermal administration of testosterone (TT) has been shown to be effective, but little is known on the long-term effects of in boys with CDGP.

Study design: Retrospective study in a single tertiary center of pediatric endocrinology.

Patients and Methods: The clinical records of 40 patients with CDGP who completed a long-term clinical evaluation were retrospectively analyzed. At the start of treatment, their mean (SD) age was 14 (0, 8) y, mean bone age was 12. 3 (0. 6) y, mean height standard deviation score (HSDS) was -1. 93 (0. 7), mean height velocity SDS (HVSDS) was -3. 26 (1. 78), mean BMI SDS was -0. 8 (1. 1), mean target height SDS (THSDS) was -0. 5 (0. 6), mean testicular volume (TV) was 4. 6 (1. 0) ml, and mean T concentration was 65. 2 (36. 6) ng/dl. All known causes of delayed growth and puberty had been excluded. Informed consent was obtained from the patients and from their legal guardians. All subjects were treated with TT gel (2%) at the dose of 10 mg/day for 3 months. They were re-evaluated after 6 months and 1 year from the start of treatment and at the attainment of adult height (HV<2 cm/y).

Results: After 6 months mean HSDS was -1. 76 (0. 91), and mean TV was 7. 4 (3. 2 ml). After 1 y mean HSDS was -1. 55 (0. 78), TV was 11, 5 (3. 7 ml), and mean T concentration was 281 (103) ng/dl. Mean adult HSDS was -0. 5 (0. 8) at a mean age of 18. 9 (1. 1) y, with a mean TV of 11. 4 (3. 7) ml, mean T concentration of 433 (90) ng/dl, and mean BMI SDS was -0. 39 (0. 9). The mean increase in HSDS between treatment start and adult height was 1. 3 (0. 65). All subjects reached their genetic TH. Treatment was well tolerated and did not induce noticeable side effects.

Conclusions: This study shows that a 3 months course of TT accelerates growth and pubertal progression and has no detrimental effects on adult height.