title: Normal bone mineral content but unfavourable muscle/fat ratio in Klinefelter syndrome.
abstract: OBJECTIVE
  To evaluate body composition and bone mineral content (BMC) in children and adolescents with Klinefelter syndrome (KS).
  
  
  METHODS
  Retrospective cross-sectional study.
  
  
  METHODS
  Tertiary endocrine clinic at the University Hospital, Copenhagen.
  
  
  METHODS
  Eighteen untreated boys with KS and six boys with KS receiving androgen substitution with a median age of 11.0 years (range 4.3-18.6) participated in the study.
  
  
  METHODS
  Dual energy x ray absorptiometry and anthropometric measurements were analysed.
  
  
  METHODS
  Lumbar and whole body BMC, lean body mass (LBM), body fat mass (BFM), body fat percentage (BF%), height and body mass index (BMI) were compared between treated and untreated boys with KS and compared to normal age-matched boys.
  
  
  RESULTS
  LBM (untreated -0.3 (-2.4 to +2.1) and treated +1.1 (-1.6 to +2.1)) was normal, while BFM (untreated +0.5 (-1.0 to +2.3), p = 0.02 and treated +1.6 (-0.2 to +2.4), p = 0.01) was significantly increased, all expressed as standard deviation scores. Lumbar bone mineral density (BMD; untreated -0.4 (-3.1 to +0.9) and treated +1.0 (-1.4 to +3.0)) and whole body BMC (untreated +0.1 (-1.8 to +3.3) and treated +1.5 (-1.1 to +2.5)) were normal.
  
  
  CONCLUSIONS
  We found significantly increased BFM and BF% despite normal LBM, suggesting the presence of an unfavourable muscle/fat ratio. Lumbar BMD and whole body BMC were normal. These findings suggest that the unfavourable metabolic profile seen in adult KS may already be present in childhood as evidenced by the increased fat mass, whereas the reported low BMD seems to develop after puberty.
authors.affiliation: University Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. lise.aksglaede@rh.regionh.dk
authors.forename: L
authors.initials: L
authors.lastname: Aksglaede
authors.forename: C
authors.initials: C
authors.lastname: Molgaard
authors.forename: N E
authors.initials: NE
authors.lastname: Skakkebaek
authors.forename: A
authors.initials: A
authors.lastname: Juul
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000728:Androgens / Q000627:therapeutic use; D050218:Body Fat Distribution; D015519:Bone Density / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004958:Estradiol / Q000097:blood; D005640:Follicle Stimulating Hormone / Q000097:blood; D020249:Hormone Replacement Therapy; D006801:Humans; D007713:Klinefelter Syndrome / Q000097:blood / Q000503:physiopathology*; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D012189:Retrospective Studies; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood / Q000627:therapeutic use
chemical_list: D000728:Androgens; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; C010792:testosterone undecanoate