title: Are adolescent boys with Klinefelter syndrome androgen deficient? A longitudinal study of Finnish 47,XXY boys.
abstract: Testosterone (T)-substitution therapy is widely used in adult patients with Klinefelter syndrome (KS) to prevent symptoms and sequels of androgen deficiency, but it is currently unknown if adolescent boys with KS benefit from early T therapy. To evaluate the optimal age to start T substitution, we searched for signs of androgen deficiency in pubertal boys with KS. 14 nonmosaic 47,XXY boys, aged 10-13.9 y, were followed up for 4-37 mo with staging of puberty and frequent reproductive hormone measurements. Furthermore, indices reflecting androgen action (serum SHBG, leptin, and prostate-specific antigen (PSA) levels) were studied. Both onset and progression of puberty according to Tanner stages were normal in boys with KS. Consistently, serum T concentrations increased as expected and remained normal throughout follow-up. Changes in the indices of androgen action (decreases in serum SHBG and leptin, and increase in serum PSA concentrations) occurred normally, except that average leptin levels were higher in the boys with KS (KS boys 11.8 +/- 7.0 microg/L; controls 7.6 +/- 4.7 microg/L; p = 0.033). Despite normal T concentrations, the KS boys displayed from the age of 13 y elevated serum FSH and LH levels, and exaggerated gonadotropin responses to gonadotropin-releasing hormone. These data do not demonstrate an unequivocal androgen deficiency in adolescent boys with KS that would necessitate androgen supplementation therapy during early puberty.
authors.affiliation: Hospital for Children and Adolescents, Helsinki University Central Hospital, University of Helsinki, 00029 Helsinki, Finland. anne.wikstrom@fimnet.fi
authors.forename: Anne M
authors.initials: AM
authors.lastname: Wikström
authors.forename: Leo
authors.initials: L
authors.lastname: Dunkel
authors.forename: Sanna
authors.initials: S
authors.lastname: Wickman
authors.forename: Ensio
authors.initials: E
authors.lastname: Norjavaara
authors.forename: Carina
authors.initials: C
authors.lastname: Ankarberg-Lindgren
authors.forename: Taneli
authors.initials: T
authors.lastname: Raivio
mesh_terms: D000293:Adolescent; D000728:Androgens / Q000172:deficiency*; D005640:Follicle Stimulating Hormone / Q000097:blood; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D006801:Humans; D007621:Karyotyping; D007713:Klinefelter Syndrome / Q000235:genetics*; D020738:Leptin / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011627:Puberty; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000097:blood
chemical_list: D000728:Androgens; D020738:Leptin; D012738:Sex Hormone-Binding Globulin; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D017430:Prostate-Specific Antigen