ESPE Abstracts

Introduction: Short stature is the most common symptom of Turner Syndrome (TS). The height below the 3rd percentile is an indication for recombinant human growth hormone (rhGH) treatment. TS is also associated with gonadal failure and increased risk of fracture. Spinal trabecular bone score (TBS) is a novel bone imaging tool that can offer better bone evaluation in TS.

Aim: To evaluate TBS in TS, its association with rhGH therapy, and selected parameters related to the calcium-phosphate balance.

Study group: The study group consisted of 52 patients with TS, diagnosed in one pediatric tertiary centre, aged 4.8 to 18.9 years who underwent dual-energy X-ray absorptiometry (DXA). Biochemical parameters were measured: IGF-1 (ng/ml), IGFBP-3 (mg/ml), 25-OHvitaminD (ng/ml), calcium (Ca, mg/dl), phosphate (P, mg/dl), alkaline phosphatase (ALP, U/l). Blood was sampled in the morning in fasting conditions. SDS for height, BMI, IGF-1, and IGFBP-3 was calculated. The obtained data was subjected to statistical analysis. 46 of patients were treated with rhGH given subcutaneously once daily at bedtime, in a dose 0.05 mg/kg/day. Six patient were never treated with rhGH because their growth was above 3 percentile. The patients were divided into three groups: X monosomy (group 1), numerical aberrations (group 2), and structural aberrations (group 3). Patients with coexisting endocrine diseases or other conditions which could interfere with estimated parameters were excluded.

Results: Mean age of TS patients was 12.5 +/- 4 years. Mean time of rhGH treatment in the whole group was 4.4 +/-3.3 years. The time of treatment with rhGH was the longest in group 1 (5.96) vs group 2 (3.21) and group 3 (3.40) (P=0.041). There were no statistically significant differences in TBS by karyotype. There was a positive correlation between TBS and the age of the patients (0.78; P<001), time of GH treatment (0.34; P=0.0154), height SDS (0.29; P=0.0416), but no BMI SDS (0.21; P=0.141) TBS correlated negatively with ALP (-0.46, P=0.021), and phosphorus (-0.69; P<0.001). The correlation between TBS and IGF-1 SDS was below statistical significance (-026; P=0.0845).

Conclusions: Normal value of TBS confirms that bone architecture is not disturbed in young girls with TS. Therapy with rhGH may have a positive effect on TBS and reduce fracture risk in TS although this process is more complex and demand prospective research.