Endocrine Abstracts

Background: Decreased bone mineral density using dual energy absorptiometry (DXA) is reported in mixed cohorts of testosterone treated and testosterone naïve men with Klinefelter syndrome (KS). Bone mass and body composition in men with congenital anorchia (CA) have not been reported.

Hypothesis: Men with KS and CA treated with testosterone from adolescence have normal bone mass and body composition.

Methods: DXA and pQCT were performed in 20 hypogonadal men (12 KS and eight CA), all and compared with 20 aged matched healthy controls. Results expressed as median (range).

Results: Age, height, BMI were not different between groups. No differences were seen between patients and controls for the following parameters-DXA total body BMD Z score −0.7 (−2.4, +3.0) vs −0.6 (−2.3, +1.2) (P=0.93); pQCT total density Z score at 4% radius: −1.1 (−3.2,+2.6) vs −1.4 (−3.5,+1.4) (P=0.13), cortical density: 469.5 mg/cm³(301,753.1) vs 466.1 mg/cm³(271.4, 723.2) (P=0.28) and trabecular density: 223.7 mg/cm³(151.9, 334) vs 198.6 mg/cm³(147, 263.9) (P=0.06). DXA lean mass, lean mass for height and lean mass for fat mass were similar in both groups. Muscle density and muscle area on pQCT at 66% tibia were not different between patients and controls: 77.4 mg/cm³(56.7, 80.4) vs 77.4 mg/cm³(73.7, 80.7) (P=0.86) and 8079 cm² (6486.4, 1922.6) vs 8122.2 cm²(5429.1, 10 258.60 (P=0.92).%fat was similar in both groups but trunk: leg fat ratio1.53 (0.88, 3.0) vs 1.17 (0.78, 2, 42) (P=0.01), visceral adiposity mass: 464.9 g (156.5, 981.5) vs 289.3 (137.2, 582.2) (P=0.006) and volume: 502.6 cm²(169.2, 1061.1) vs 312.8 cm²(148.3, 629.4) (P=0.006)were higher for patients.

Conclusion: This first report of bone assessment using pQCT in adults with KS and CA treated with testosterone from adolescence demonstrates BMD within the normal population range, without deficits in cortical or trabecular bone. However, despite androgen replacement, increased central adiposity was seen and this requires further exploration.