Background: GH deficiency (GHD) is currently defined as secondary IGF1 deficiency (IGFD). In the patients with normal GH secretion and IGFD, significant increase of IGF1 during generation test excludes primary IGFD, however is not an approved indication for GH therapy.
Objective and hypotheses: The aim of the study was to assess GH therapy effectiveness in children with IGFD, responding to short-term GH administration despite normal GH peak after falling asleep and in stimulating tests.
Method: Analysis comprised 42 patients with spontaneous (after falling asleep) and stimulated GH peak >10.0 ng/ml, and IGFD (IGF1 SDS for age and sex <−1.0), in whom IGF1 concentrations at least doubled and normalised during generation test, subjected to GH therapy. First-year response to treatment: height velocity (HV) increase and IGF1 SDS increase was assessed in all of them, final height FH in 28 patients. The therapy effectiveness was compared with 110 children with partial GHD (pGHD), including 42 treated up to FH.
Results: In IGFD group, height SDS before treatment (hSDS-0) was −2.87±0.72, in first year of treatment HV increased from 3.8±0.9 to 9.4±1.9 cm/year, IGF1 SDS increased from −2.19±0.78 to 0.34±1.07, FH SDS was −1.14±0.82 and increased by 1.61±1.08 SDS with respect to hSDS-0. In pGHD group, hSDS-0 was −2.79±0.59, HV increased from 3.8±1.4 to 9.8±2.1 cm/year, IGF1 SDS increased from −1.76±0.88 to 0.52±0.87, and FH SDS was −1.20±0.80 and increased by 1.48±0.83 vs. hSDS-0. The differences in age, GH dose, therapy duration and all the analysed indices of GH therapy effectiveness between the groups were insignificant.
Conclusion: Children with short stature, normal spontaneous and stimulated GH secretion and decreased IGF1 concentrations which increase significantly in generation test, may benefit during GH therapy similarly to children with pGHD. It seems worth considering not diagnose idiopathic short stature in such patients.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology