ESPE Abstracts

Background and aims: Existence and diagnostic procedures of neurosecretory dysfunction (NSD) are still a matter of debate. The aim of the study was to analyse prediagnostic data of short-statured children with pathologic and normal spontaneous GH-secretion and to evaluate the effect of GH-therapy in NSD-patients.

Methods: Of 90 children aged 3–16 years, in whom 12-hour night profiles for GH-secretion were performed (unicentric), in 49 NSD was diagnosed. Their auxologic data, IGF-I /IGFBP3-levels, GH-stimulation tests as well as spontaneous overnight GH-secretion were analysed and compared to data from children with normal spontaneous GH-secretion. Additionally, follow-up auxological data of the NSD-patients during GH-treatment were collected.

Results: Age, prediagnostic auxologic data (height, weight, HSDS, HV, HV-SDS), delay of bone age and IGF-I/IGFBP3-levels did not differ between the two groups. Mean GH-response in clonidine tests was lower in NSD-children, but results widely overlapped (10.58±4.63 ng/ml vs 14.36±8.29 ng/ml). Instead, for all criteria of spontaneous GH-secretion a significant difference was found (number of peaks: 2.90±1.13 vs 3.85±0.99, maximal secretion: 10.23±4.14 vs 18.27±6.58 ng/ml, mean secretion: 2.39±0.54 vs 4.36±0.88 ng/ml) with mean secretion showing no overlap between the two groups. Children with NSD showed a good response to GH-treatment after 1 (ΔHSDS +0.77±0.48, ΔHV-SDS: 4.4±3.51 cm/year) as well as 4 years (ΔHSDS: +1.51±0.75, ΔHV-SDS: 0.77±1.86 cm/year). These results are similiar to those of children with idiopathic GHD and as in these, a significant relation of treatment effect with age was seen. Children diagnosed <10 years showed better responses after the first year although in 40% of the older ones a good benefit was found, too.

Conclusion: According to our results, analysing overnight GH-secretion remains the only method to identify NSD. Yet, as response to GH-treatment is comparable to results in idiopathic GHD, it is worth to consider this diagnosis.