Systemic effects of transdermal testosterone for the treatment of microphallus in children.
OBJECTIVE
To elucidate the metabolic effects of topical testosterone for the treatment of microphallus in children.


METHODS
We administered 5% testosterone ointment to 50 prepubertal boys for the treatment of microphallus, allowing us to observe its metabolic effect on plasma concentrations of testosterone as a marker of transdermally absorbed testosterone, insulin-like growth factor (IGF)-I as a marker of growth hormone secretion status, and osteocalcin as a marker of bone metabolic turnover.


RESULTS
Transdermal application of testosterone for 30 days at a dose that affects penile growth increased mean (+/-SD) plasma testosterone concentrations from 7.5+/-5.1 to 31.0+/-8.2 ng/dL (pre- vs. post-treatment, respectively; P<0.01). This was associated with a slight but statistically significant elevation of IGF-I concentrations (117.2+/-76.9 vs. 154.4+/-81.5 ng/mL; P<0.05). No significant change in osteocalcin levels was found.


CONCLUSIONS
When using testosterone ointment as a treatment for microphallus, it should be borne in mind that this application has systemic effects.
Arisaka
O
O
Department of Pediatrics, Dokkyo University School of Medicine, Mibu, Japan.
Hoshi
M
M
Kanazawa
S
S
Nakajima
D
D
Numata
M
M
Nishikura
K
K
Oyama
M
M
Nitta
A
A
Kuribayashi
T
T
Kano
K
K
Nakayama
Y
Y
Yamashiro
Y
Y
D000279:Administration, Cutaneous; D015415:Biomarkers / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007006:Hypogonadism / Q000188:drug therapy* / Q000378:metabolism; D007223:Infant; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D015675:Osteocalcin / Q000097:blood; D013739:Testosterone / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use*
D015415:Biomarkers; D015675:Osteocalcin; D013739:Testosterone; D007334:Insulin-Like Growth Factor I