Human Chorionic Gonadotropin Stimulation Test in Prepubertal Children with Micropenis Can Accurately Predict Leydig Cell Function in Pubertal or Postpubertal Adolescents.
OBJECTIVE
To evaluate the accuracy of the human chorionic gonadotropin (hCG) stimulation test in children with micropenis in predicting later Leydig cell function.


METHODS
We conducted a retrospective investigation of testosterone response to a 3-day hCG test (3,000 IU/m2/day) in prepuberty to indicate the need for hormone replacement therapy (HRT) in adolescence.


RESULTS
Fifty Japanese boys (range, 0.8-15.4 years of age; median, 8.9) with micropenis were enrolled. Thirty-four spontaneously developed puberty and preserved the ability of testosterone production (group 1), while 16 did not develop any pubertal signs without HRT (group 2). Serum testosterone levels after the hCG test (post-hCG T) in group 2 (range, <0.05-1.1 ng/ml; median, 0.24) were significantly lower than in group 1 (range, 0.5-8.7 ng/ml; median, 2.4; p < 0.0001). Based on true positives who required continuous HRT, the area under the receiver-operating characteristics curve for post-hCG T was 0.983 [95% confidence interval (CI), 0.90-1.00]. The post-hCG T cut-off level corresponding to the Youden index was 1.1 ng/ml (95% CI, 1.0-1.1), with a sensitivity of 100.0% (95% CI, 79.4-100.0) and a specificity of 94.1% (95% CI, 80.3-99.3).


CONCLUSIONS
The hCG test in prepubertal children with micropenis can be useful for predicting Leydig cell function in pubertal or postpubertal adolescents. The post-hCG T cut-off level of 1.1 ng/ml is recommended to screen for those who will likely require HRT for pubertal development.
Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.
Tomohiro
T
Ishii
Nobutake
N
Matsuo
Seiji
S
Sato
Tsutomu
T
Ogata
Shinya
S
Tamai
Makoto
M
Anzo
Tsutomu
T
Kamimaki
Goro
G
Sasaki
Mikako
M
Inokuchi
Naoaki
N
Hori
Naoko
N
Amano
Satoshi
S
Narumi
Hironori
H
Shibata
Tomonobu
T
Hasegawa
D000293:Adolescent; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D005640:Follicle Stimulating Hormone / Q000097:blood; D005832:Genital Diseases, Male / Q000175:diagnosis*; D007987:Gonadotropin-Releasing Hormone / Q000097:blood / Q000494:pharmacology; D020249:Hormone Replacement Therapy; D006801:Humans; D007223:Infant; D007985:Leydig Cells / Q000187:drug effects*; D008297:Male; D010413:Penis / Q000002:abnormalities* / Q000033:anatomy & histology / Q000254:growth & development; D010928:Placental Lactogen / Q000494:pharmacology*; D011627:Puberty; D012189:Retrospective Studies; D013268:Stimulation, Chemical; D013739:Testosterone / Q000097:blood
D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D005640:Follicle Stimulating Hormone; D010928:Placental Lactogen