Osteoporosis and Klinefelter's syndrome

Clin Endocrinol (Oxf). 1992 Jan;36(1):113-8. doi: 10.1111/j.1365-2265.1992.tb02910.x.


Objective: We wanted to measure forearm mineral density and bone-related biochemical variables in patients with Klinefelter's syndrome.

Design: Measurements made in patients with Klinefelter's syndrome were compared to those obtained in age-matched normal male volunteers.

Patients: We studied 22 patients with Klinefelter's syndrome (12 of whom had received sex hormone therapy) and 22 control subjects.

Measurements: We measured forearm mineral density, forearm fat content, fat-corrected forearm mineral density, plasma calcium and ionized calcium, serum osteocalcin, testosterone and dehydroepiandrosterone sulphate, and urinary hydroxyproline/creatinine ratio.

Results: Forearm mineral density was lower in the Klinefelter's group than in the control subjects (P less than 0.05) and below the control range in 5 patients. The fat content of the forearm was greater in the Klinefelter's group (P less than 0.002). Serum osteocalcin and testosterone were lower, while ionized calcium and the urinary hydroxyproline/creatinine ratio were higher in the Klinefelter's group (P less than 0.002). Serum dehydroepiandrosterone sulphate and testosterone were significantly related in the Klinefelter's group (r = 0.64, P less than 0.001), but not in the controls (r = 0.22, NS). Forearm mineral density and fat-corrected forearm mineral density were significantly related to serum testosterone in the Klinefelter's group (r less than 0.63; P less than 0.01), but not in the control subjects (r less than 0.03, NS).

Conclusions: Decreased bone density occurs in about 25% of patients with Klinefelter's syndrome and probably reflects both decreased bone formation and increased bone resorption.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Body Composition / physiology
  • Bone Density / physiology
  • Creatinine / urine
  • Dehydroepiandrosterone / blood
  • Humans
  • Hydroxyproline / urine
  • Klinefelter Syndrome / blood
  • Klinefelter Syndrome / complications*
  • Klinefelter Syndrome / urine
  • Male
  • Middle Aged
  • Osteocalcin / blood
  • Osteoporosis / etiology*
  • Testosterone / blood


  • Osteocalcin
  • Testosterone
  • Dehydroepiandrosterone
  • Creatinine
  • Hydroxyproline