Changes in circadian rhythm of prolactin in short children are dependent on growth hormone secretion

introduction and objective. Taking into consideration the common ontogenic origin of prolactin (Prl) and growth hormone (GH), the Prl circadian pattern was analysed in children with different degrees of GH deficiency (GHD). materials and methods. The analysis comprised 100 short children (31 girls and 69 boys), aged: 10.1±3.51 years. Based on maximal GH secretion (GHmax) during two stimulating tests multiple hormone deficiency (MPHD), severe isolated GHD (SIGHD), partial isolated GHD (PIGHD) or idiopathic short stature (ISS) were diagnosed. Non-inferential chronobiometry (macroscopic analysis) of the circadian Prl rhythm, based on serum Prl measured every 3 hours during 24 hours, was performed. In this analysis, mesor, the area under curve (AUC), peak and trough level, dispersion, mean nocturnal and diurnal concentration, night/day ratio, amplitude and regression index were estimated. results. In the study group, the positive correlations between GHmax and Prl concentrations at 02:00 and at 05:00 were observed, as well as between GHmax and mesor, amplitude, mean nocturnal concentration, night/day ratio and AUC. The nocturnal rise of Prl secretion was blunted in 100% MPHD and 50% SIGHD children, whereas in most children with PIGHD and ISS, the circadian Prl rhythm was normal. conclusions. 1) In short children, the lower the concentration of GH is, the more blunted nocturnal Prl secretion becomes. 2) In the majority of MPHD and SIGHD children (but not PIGHD), the circadian Prl rhythm was disturbed; namely, reduced nocturnal Prl secretion was noticeable

Limited usefulness of the test of spontaneous growth hormone (GH) nocturnal secretion as a screening procedure in diagnosing GH deficiency in children with short stature

[b]introduction and objective[/b]. In Poland, the assessment of nocturnal GH secretion has gained the status of screening test; however, this procedure is not included in international recommendations. The aim of the study was to assess the accuracy and predictive value of the test of nocturnal GH secretion as a screening procedure in diagnosing GHD, and to check the adequacy of the cut-off value for GH peak in this test on the level of 10 ng/ml. [b]materials and methods. [/b]The analysis comprised the data of 1,000 children with short stature. In all the patients, GH secretion was assessed in a screening test (after falling asleep) and in 2 stimulating tests (reference tests), with simultaneous assessment of IGF-I secretion before stimulating tests. The indices of screening test accuracy, likelihood ratios and predictive values were assessed. The cut-off level of GH peak after falling asleep, ensuring its 95% sensitivity, was calculated in ROC curve analysis. [b]results[/b]. Sensitivity of the screening test was 70.4%, while the specificity – 61.2%, positive likelihood ratio – 1.842, negative likelihood ratio – 0.482, positive predictive value – 0.462, negative predictive value – 0.812. The sensitivity of the test of GH secretion after falling asleep is too low with respect to the requirements for screening test. The ROC curve analysis showed 95% sensitivity for the screening test on the level of 19.0 ng/ml; however, with a very low specificity – below 25%, thus making this test completely useless as a screening procedure. [b]conclusions.[/b] The obtained results strongly contradict the opinion that the assessment of GH secretion after falling asleep should be a screening test in diagnosing GHD in children with short stature

Association of human height-related genetic variants with familial short stature in Han Chinese in Taiwan

[[abstract]]Human height can be described as a classical and inherited trait model. Genome-wide association studies (GWAS) have revealed susceptible loci and provided insights into the polygenic nature of human height. Familial short stature (FSS) represents a suitable trait for investigating short stature genetics because disease associations with short stature have been ruled out in this case. In addition, FSS is caused only by genetically inherited factors. In this study, we explored the correlations of FSS risk with the genetic loci associated with human height in previous GWAS, alone and cumulatively. We systematically evaluated 34 known human height single nucleotide polymorphisms (SNPs) in relation to FSS in the additive model (p < 0.00005). A cumulative effect was observed: the odds ratios gradually increased with increasing genetic risk score quartiles (p < 0.001; Cochran-Armitage trend test). Six affected genes—ZBTB38, ZNF638, LCORL, CABLES1, CDK10, and TSEN15—are located in the nucleus and have been implicated in embryonic, organismal, and tissue development. In conclusion, our study suggests that 13 human height GWAS-identified SNPs are associated with FSS risk both alone and cumulatively.[[notice]]補正完