RESUMO
AIMS AND METHODS: Prediction algorithms suggest factors determining short- and long-term growth response to growth hormone (GH) in Turner's syndrome (TS). A total of 133 patients (group A; 53% with karyotype 45,X) completed 1 year of treatment and 77 patients (group B) reached adult height (AH) after >4 years on GH treatment. The patients were analysed for factors determining the outcomes, and in addition, the validity of published algorithms was tested. RESULTS: In group A [values are given as medians (10th-90th percentiles)], starting age was 9.4 (4.8-14) years, height was -3.2 (-4.4 to -1.9) SDS (Prader references), and GH dose was 38 (23-48) µg/kg/day. Observed height velocity was 7.7 (5.2-9.8) cm/years and was equal to the predicted height velocity. In group B, projected adult height (PAH) was 147.4 (139.5-154.8) cm. Total gain in height over PAH of 6.1 (2.0-12.6) cm was negatively correlated with height at start, but positively correlated with GH duration, first year Δheight SDS, or index of responsiveness. Observed AH was 153.5 (146.6-160.1) cm and predicted AH was 155.0 (147.4-161.0) cm, which is statistically not different. On GH <5% IGF-I levels were >2 SDS. CONCLUSIONS: The published prediction algorithms were found to be valid. If normal AH is to be reached at the lowest costs and risks, probably only TS children with a good growth potential and a high responsiveness to GH can be treated successfully with GH doses of <50 µg/kg/day.