Reference ranges for two automated chemiluminescent assays for serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3)

Challenges of insulin-like growth factor-1 testing

Insulin-like growth factor 1 (IGF-1), primarily synthesized in the liver, was initially discovered due to its capacity to replicate the metabolic effects of insulin. Subsequently, it emerged as a key regulator of the actions of growth hormone (GH), managing critical processes like cell proliferation, differentiation, and apoptosis. Notably, IGF-1 displays a longer half-life compared to GH, making it less susceptible to factors that may affect GH concentrations. Consequently, the measurement of IGF-1 proves to be more specific and sensitive when diagnosing conditions such as acromegaly or GH deficiency. The recognition of the existence of IGFBPs and their potential to interfere with IGF-1 immunoassays urged the implementation of various techniques to moderate this issue and provide accurate IGF-1 results. Additionally, in response to the limitations associated with IGF-1 immunoassays and the occurrence of discordant IGF-1 results, modern mass spectrometric methods were developed to facilitate the quantification of IGF-1 levels. Taking advantage of their ability to minimize the interference caused by IGF-1 variants, mass spectrometric methods offer the capacity to deliver robust, reliable, and accurate IGF-1 results, relying on the precision of mass measurements. This also enables the potential detection of pathogenic mutations through protein sequence analysis. However, despite the analytical challenges, the discordance in IGF-1 reference intervals can be attributed to a multitude of factors, potentially leading to distinct interpretations of results. The establishment of reference intervals for each assay is a demanding task, and it requires nationwide multicenter collaboration among laboratorians, clinicians, and assay manufacturers to achieve this common goal in a cost-effective and resource-efficient manner. In this comprehensive review, we examine the challenges associated with the standardization of IGF-1 measurement methods, the minimization of pre-analytical factors, and the harmonization of reference intervals. Particular emphasis will be placed on the development of IGF-1 measurement techniques using "top-down" or "bottom-up" mass spectrometric methods.

Transient Isolated, Idiopathic Growth Hormone Deficiency-A Self-Limiting Pediatric Disease with Male Predominance or a Diagnosis Based on Uncertain Criteria? Lesson from 20 Years' Real-World Experience with Retesting at One Center

In the majority of children with growth hormone (GH) deficiency (GHD), normal GH secretion may occur before the attainment of final height. The aim of the study was to assess the incidence of persistent and transient GHD and the effectiveness of recombined human GH (rhGH) therapy in children with isolated, idiopathic GHD with respect to the moment of therapy withdrawal and according to different diagnostic criteria of GHD. The analysis included 260 patients (173 boys, 87 girls) with isolated, idiopathic GHD who had completed rhGH therapy and who had been reassessed for GH and IGF-1 secretion. The incidence of transient GHD with respect to different pre- and post-treatment criteria was compared together with the assessment of GH therapy effectiveness. The incidence of transient GHD, even with respect to pediatric criteria, was very high. Normal GH secretion occurred before the attainment of near-final height. Application of more restricted criteria decreased the number of children diagnosed with GHD but not the incidence of transient GHD among them. Poor response to GH therapy was observed mainly in the patients with normal IGF-1 before treatment, suggesting that their diagnosis of GHD may have been a false positive. Further efforts should be made to avoid the overdiagnosis GHD and the overtreatment of patients.

Insulin-like growth factor 1 and sex hormones for assessment of anthropometric and pubertal growth of Egyptian children and adolescents with type 1 diabetes mellitus (single center study)

BACKGROUND

This study aimed to assess the anthropometric measures and pubertal growth of children and adolescents with Type 1 diabetes mellitus (T1DM) and to detect risk determinants affecting these measures and their link to glycemic control.

PATIENTS AND METHODS

Two hundred children and adolescents were assessed using anthropometric measurements. Those with short stature were further evaluated using insulin-like growth factor 1 (IGF-1), bone age, and thyroid profile, while those with delayed puberty were evaluated using sex hormones and pituitary gonadotropins assay.

RESULTS

We found that 12.5% of our patients were short (height SDS < -2) and IGF-1 was less than -2 SD in 72% of them. Patients with short stature had earlier age of onset of diabetes, longer duration of diabetes, higher HbA1C and urinary albumin/creatinine ratio compared to those with normal stature (p < 0.05). Additionally, patients with delayed puberty had higher HbA1c and dyslipidemia compared to those with normal puberty (p < 0.05). The regression analysis revealed that factors associated with short stature were; age at diagnosis, HbA1C > 8.2, and albumin/creatinine ratio > 8 (p < 0.05).

CONCLUSION

Children with uncontrolled T1DM are at risk of short stature and delayed puberty. Diabetes duration and control seem to be independent risk factors for short stature.

Sirtuin 1 serum concentration in healthy children - dependence on sex, age, stage of puberty, body weight and diet

Introduction

Sirtuin 1 (SIRT1) is known to be involved in sensing cellular energy levels and regulating energy metabolism. This study aimed to evaluate fasting serum SIRT1 levels in healthy children, and to analyse the influence of age, sex, puberty, body weight, height, and diet on its concentration.

Methods

47 healthy children aged 4-14 with weight and height within normal range and no chronic disease were included into the study. Fasting serum SIRT1 concentrations were estimated by Enzyme Linked Immunosorbent Assay (ELISA).

Results

Results showed that serum SIRT1 concentrations in healthy children did not differ with respect to sex, age, height, weight and puberty. Whereas, it appeared that a higher frequency of fruits, vegetables and dairy products consumption was associated with an increase in serum SIRT1 levels.

Discussion

Studying SIRT1 in the context of children's health may have implications for a broader understanding of growth processes, pubertal development, metabolic disorders and nutrition.

Insulin-like growth factor-1 and cognition in normoglycemia, prediabetes, and type 2 diabetes mellitus

BACKGROUND

The relationship between insulin-like growth factor-1 (IGF-1) and cognition has been studied in healthy individuals, but not extensively with regards to insulin resistance and type 2 diabetes mellitus (T2DM). In this retrospective observational study, we investigated relationships of IGF-1 with memory and executive function across people with normoglycemia, prediabetes, and T2DM.

METHODS

Data from the Midlife in the United States (MIDUS) study were used. Episodic memory and executive function were assessed using the Brief Test of Adult Cognition by Telephone approximately 21.42 ± 12.10 months prior to measuring IGF-1 levels from a fasting blood sample. Normoglycemia was identified as individuals without a physician diagnosis of diabetes and glycated hemoglobin (HbA1c) ≤5.6%. Prediabetes was identified as those without a physician diagnosis of diabetes and HbA1c between 5.7%-6.4%. T2DM was identified as anyone with a physician diagnosis of diabetes, or HbA1c ≥6.5%, or anyone using an oral hypoglycemic medication. The associations were assessed using linear regressions controlling for age, sex, education, body mass index, C-reactive protein, HbA1c or homeostatic model of insulin resistance, MIDUS wave, exercise, smoking status, sleep quality, alcohol intake, oral hypoglycemic use, and insulin use.

RESULTS

The study included 1400 participants, which consisted of 583 normoglycemic (48.4% female, mean age 51.0 ± 12.2 years), 512 prediabetes (58.4% female, mean age 57.3 ± 11.8 years), and 305 T2DM participants (53.8% female, mean age 57.6 ± 11.5 years). Peripheral IGF-1 concentrations were lower (F2,1397 = 28.29, p < 0.001) in people with prediabetes or T2DM, vs. normoglycemia. Participants with prediabetes or T2DM had lower episodic memory (F2,1397 = 9.21, p < 0.001) and executive function (F2,1397 = 20.29, p < 0.001) composite z-scores than people with normoglycemia. Higher IGF-1 concentrations were associated with better executive performance in individuals with prediabetes (β = 0.115 [0.028, 0.202], p = 0.010), but not in individuals with normoglycemia or T2DM. An interaction between IGF-1 and sex in predicting executive function was observed in the prediabetes group (β = -0.344, p = 0.042), where the relationship was weaker in females (β = 0.106 [-0.012, 0.224], p = 0.077) than males (β = 0.251 [0.123, 0.380], p < 0.001). No associations were seen between IGF-1 and memory.

CONCLUSION

The results suggest that peripheral IGF-1 concentrations may be related to executive function, and that the relationship may be sex-specific and dependent on diabetes status.

Effect of Anamorelin, a Ghrelin Receptor Agonist, on Muscle and Bone in Adults With Osteosarcopenia

CONTEXT

Anamorelin, a ghrelin receptor agonist known to stimulate the pulsatile release of GH from the pituitary, has the potential to improve musculoskeletal health in adults with osteosarcopenia.

OBJECTIVE

To determine the effect of anamorelin treatment for 1 year on muscle mass and strength and on biochemical markers of bone turnover in adults with osteosarcopenia (OS).

DESIGN

Randomized, placebo-controlled, 1-year anamorelin intervention trial.

SETTING

The Bone Metabolism Laboratory at the USDA Nutrition Center at Tufts University.

PARTICIPANTS

26 men and women, age 50 years and older, with OS.

MAIN OUTCOME MEASURES

Muscle mass by D3-creatine dilution and lean body mass (LBM) and bone mineral density (BMD) by dual-energy X-ray absorptiometry, muscle strength, serum IGF-1, and bone turnover markers, serum procollagen 1 intact N-terminal (P1NP), and C-terminal telopeptide (CTX).

RESULTS

Anamorelin did not have a significant effect on muscle mass or LBM; it significantly increased knee flexion torque at 240°/s by 20% (P = .013) and had a similar nonstatistically significant effect on change in knee extension; it increased bone formation (P1NP) by 75% (P = .006) and had no significant effect on bone resorption (CTX) or BMD. Serum IGF-1 increased by 50% in the anamorelin group and did not change in the placebo group (P = .0001 for group difference).

CONCLUSION

In this pilot study, anamorelin did not significantly alter muscle mass; however, it may potentially improve lower extremity strength and bone formation in addition to increasing circulating IGF-1 levels in adults with OS. Further study of anamorelin in this population is warranted.

3M syndrome: Evaluating the clinical and laboratory features and the response of the growth hormone treatment: Single center experience

INTRODUCTION & OBJECTIVE

3 M Syndrome is a rarely encountered autosomal recessive syndrome characterized by low birth weight, severe postnatal growth deficiency, and minor dysmorphic abnormalities. 3 M-related short stature has been attributed to the resistance to growth hormone (GH) to a certain extent rather than to GH deficiency. The resistance to GH, on the other hand, has been associated with impaired protein scaffolding, transport, and p53-mediated apoptosis at the IGF-1 post-receptor pathway. In this context, the objective of this study is to evaluate the clinical, laboratory, and genetic characteristics of the patients with 3 M syndrome, detect the mutations frequently observed in these patients, and assess their response to GH treatment.

MATERIAL&METHODS

The sample of this single-center study consisted of patients diagnosed with 3 M syndrome based on genetic tests between 2007 and 2021. Patients' clinic, laboratory, and genetic characteristics pertaining to the time of admission and follow-up were recorded. All patients except one underwent a growth hormone stimulation test (GHST) (Levo-dopa or insulin tolerance test). Insulin-like growth factor (IGF) generation test was performed on those with sufficient GHST results (0.1 mg/kg/day for four days).

RESULTS

The median age of the patients, five females and three males, was 2.8 (0.25-8.12) years at admission. All but one patient were small for gestational age (SGA). The patient with normal birth weight was the baby of a diabetic mother. Obscurin-like 1 (OBSL1) variant was detected in all cases. The median height standard deviation score (SDS) at admission was -4.94 ((-5.63)- (-3.27)) SDS, and the median midparenteral height SDS was -1.27 SDS ((-3.1)- (0.34)). All patients were prepubertal at admission. The GHST response was sufficient in five cases. IGF generation test was performed in three cases. Seven patients received GH therapy (35-57 μg/kg/day). Five of these patients discontinued GH therapy since their growth velocity (GV) fell below normal during treatment. In addition, one case discontinued GH therapy because her IGF-1 value was>2 SDS, and another case received gonadotropin-releasing hormone (GnRH) analogs together with GH therapy. The median age and height SDS of the patients were 10.1 (1.79-18) years and -5.09 SDS ((-7.11)- (2.45)), respectively, as of the last follow-up visit. The height SDS values of the two cases that reached the final height were -7.11 SDS and -3.39 SDS. There were no side effects of GH treatment.

CONCLUSION

The study findings indicated a good GV during the early stages of the long-term GH treatment administered to patients with 3 M syndrome. However, response to GH therapy decreased in the following years, and the desired improvement in height SDS could not be achieved in patients who reached their final heights. Taken together with the literature data, it has been concluded that initiating GH therapy in the prepubertal period provided better outcomes than after puberty.

Turner syndrome: skin, liver, eyes, dental and ENT evaluation should be improved

Introduction

Turner syndrome association with multi-organ system comorbidities highlights the need for effective implementation of follow-up guidelines. We aimed to assess the adequacy of care with international guidelines published in 2007 and 2017 and to describe the phenotype of patients.

Methods

In this multicenter retrospective descriptive cohort study, we collected growth and pubertal parameters, associated comorbidities, treatment, and karyotype in patients diagnosed at age <18 years between 1993 and 2022. We assessed age-appropriate recommendation follow-up (children, adolescents and adults) according to the 2007 guidelines if the last visit was before 2017 (18 recommendations) and the 2017 guidelines if the last visit was after 2017 (19 recommendations).

Results

We included 68 patients followed at Lausanne University Hospital (n=64) and at Neuchatel Regional Hospital (RHNe) (n=4). 2.9% of patients underwent all recommended investigations.Overall, 68.9 ± 22.5% and 78.5 ± 20.6% of the recommendations were followed, before and after 2017 respectively. High implementation rates were found for height, weight and BMI (100%), cardiac (80 to 100%) and renal (90 to 100%) imaging. Low implementation rates were found for Ear, Nose and Throat (ENT) (56.5%), skin (38.5%), dental (23.1%), ophthalmological (10%) and cholestasis (0 to 29%) assessments, depending on age and time of visit. In adults (n=33), the mean proportion of followed recommendations was lower before than after 2017: 63.5 ± 25.8% vs. 78.7 ± 23.4%, p=0.039.

Conclusion

Growth parameters, cardiac and renal imaging are well followed. However, efforts should be made for dental, ENT, ophthalmological, skin and cholestasis assessments. Adequacy of follow-up improved with the quality of transition to adult care.

Evaluation of Adult Height in Patients with Non-Permanent Idiopathic GH Deficiency

Background: Several studies have evaluated the role of IGF-1 in the diagnosis of growth hormone deficiency (GHD). According to a recent study, an IGF-1 concentration of a −1.5 standard deviation score (SDS) appeared to be the best cut-off for distinguishing between children with GHD and normal children. This value should always be interpreted in conjunction with other clinical and biochemical parameters for the diagnosis of GHD, since both stimulation tests and IGF-1 assays have poor diagnostic accuracy by themselves. Our study was designed to evaluate the adult height (AH) in children with short stature and baseline IGF-1 concentration ≤ −1.5 SDS. Design: This retrospective analysis included 52 children and adolescents evaluated over the last 30 years for short stature and/or deceleration of the growth rate who underwent diagnostic procedures to evaluate a possible GHD. Only the patients who had baseline IGF-1 values ≤−1.5 SDS at the time of the first test were included in the study. Patients with genetic/organic GHD or underlying diseases were not included. Method: The case group consisted of 24 patients (13 boys and 11 girls) with non-permanent, idiopathic, and isolated GHD (peak GH < 10 μg/L after two provocative tests with arginine (Arg), insulin tolerance test (ITT), and clonidine (Clo), or <20 μg/L after GHRH + Arginine (GHRH+Arg); normal MRI; normal GH; and/or normal IGF-1 concentrations at near-AH). These patients were treated with GH (25–35 μg/kg/die) until near-AH. The control group consisted of 28 patients (23 boys and 5 girls) with idiopathic short stature (ISS, normal peak GH after provocative testing, no evidence of other causes for their shortness). Both groups had basal IGF-1 ≤−1.5 SDS. Results: AH and height gain in both groups were comparable. In the group of cases, mean IGF-1 SDS at the time of diagnosis was significantly lower than the levels found at the time of retesting. Conclusions: In this study, both treated patients with idiopathic GHD and untreated patients with ISS reached similar near-AHs (within target height) and showed similar increases in SDS for their height. Thus, the efficacy of treatment with rhGH in these patients may be questionable. This could be due to the fact that children with ISS are frequently misdiagnosed with GHD.

Are Serum 25-Hydroxyvitamin D Deficiency and Insufficiency Risk Factors for the Incidence of Dynapenia?

Epidemiological evidence showing the association between low 25(OH)D and age-related reduction in neuromuscular strength (dynapenia) is a paucity and controversial and, to date, the effect of osteoporosis and vitamin D supplementation on these associations has not been measured. Thus, we analyze whether serum 25(OH)D deficiency and insufficiency are risk factors for the incidence of dynapenia in individuals aged 50 or older and whether osteoporosis or vitamin D supplementation modify these associations. For that, 3205 participants of the ELSA study who were non-dynapenic at baseline were followed for 4 years. Vitamin D was measured at baseline by the serum concentration of 25(OH)D and classified as sufficient (&gt; 50 nmol/L), insufficient (≥ 30 and ≤ 50 nmol/L) or deficient (&lt; 30 nmol/L). The incidence of dynapenia was determined by a grip strength &lt; 26 kg for men and &lt; 16 kg for women at the end of the 4-year follow-up. Poisson regression models were adjusted by sociodemographic, behavioral, clinical and biochemical characteristics. Serum 25(OH)D deficient was a risk factor for the incidence of dynapenia (IRR = 1.70; 95% CI 1.04-2.79). When only individuals without osteoporosis and those who did not use vitamin D supplementation were analyzed, both serum 25(OH)D deficiency (IRR = 1.78; 95% CI 1.01-3.13) and insufficiency (IRR = 1.77; 95% CI 1.06-2.94) were risk factors for the incidence of dynapenia. In conclusion, a serum level of 25(OH)D &lt; 30 nmol/L is a risk factor for the incidence of dynapenia. Among individuals without osteoporosis and those who do not take vitamin D supplementation, the threshold of risk is higher (≤ 50 nmol/L).

Effects of Helicobacter pylori Infection on Ghrelin and Insulin-like Growth Factor 1 Secretion in Children with Idiopathic Short Stature

BACKGROUND

A diagnosis of "idiopathic short stature" (ISS) in a child means that the cause of the disease has not been established, although there are certainly some unknown factors that contributed to its occurrence. Ghrelin and leptin are important in controlling food intake; ghrelin is also a growth hormone (GH) stimulator. Both enterohormones are produced in the stomach and their secretion may be affected by a Helicobacter pylori (H. pylori) infection.

METHODS

Our study included a group of 61 children (53 prepubertal and 8 peripubertal) with ISS, without any gastrointestinal tract symptoms but in whom the histopathological evaluation of stomach tissue was made during gastroscopy to diagnose H. pylori infection. In each child, fasting ghrelin, leptin and IGF-1 concentrations, and GH levels in two stimulation tests were assessed.

RESULTS

H. pylori infection was confirmed in 24.6% of the children. Ghrelin and IGF-1 concentrations were significantly lower in H. pylori-positive than H. pylori-negative children (this was more noticeable in prepubertal subgroups), however there was not a discrepancy in regards to GH concentrations in stimulation tests, leptin levels or the nutritional state between groups.

CONCLUSIONS

Short children, infected by H. pylori seem to have lower ghrelin and IGF-1 concentrations than children without infection, this may be the reason for a worse growth rate in this subgroup.

Growth hormone treatment does not to lead to insulin resistance nor excessive rise in IGF-1 levels, while improving height in patients small for gestational age A long-term observational study

OBJECTIVE

In children born small for gestational age (SGA), the relationship between growth hormone (GH) treatment and insulin resistance (IR) has only been investigated for a short period, necessitating a longer observation period. This study aimed to evaluate the long-term (10 years) effect of GH to SGA-children on IR and safety during treatment.

DESIGN

This was a multicenter observational study.

PATIENTS

SGA-children who received GH treatment in Spain (stratified by Tanner-stage and age at GH onset [two groups: ≤6 years old or >6 years old]).

MEASUREMENTS

The analysed variables (yearly measures) included auxologic, metabolic (insulin-like growth factor-1 (IGF-1), height velocity [HV], weight and homeostatic model assessment-IR [HOMA-IR]) and safety data. Data were collected prospectively (since the study approval: 2007) and retrospectively (since the initiation of GH treatment: 2005-2007).

RESULTS

A total of 389 SGA children (369 Tanner-I) were recruited from 27 centres. The mean age (standard deviation) of the children at GH treatment onset was 7.2 (2.8) years old. IGF-1 (standard deviation score [SDS]) and HOMA-IR values tended to increase until the sixth year of GH-treatment, with significant differences being observed only during the first year, while these remained stable in the later years (within normal ranges). Height (SDS) increased significantly (basal: -3.0; tenth year: -1.13), and the maximum HV (SDS) occurred during the first year (2.75 ± 2.39).

CONCLUSIONS

HOMA-IR values increased significantly in SGA-children during the first year of GH-treatment, remained stable and were within normal ranges in all cases. Our 10-year data suggests that long-term GH treatment does not promote IR and is well-tolerated, safe and effective.

Growth Hormone/Insulin-Like Growth Factor 1 Axis Associated with Modifiers Factors in Children with Sickle Cell Anemia

BACKGROUND

Sickle cell anemia is a disease that develops episodes of acute pain and multiple organ dysfunction that can affect the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis. The severity of sickle cell anemia is influenced by modifying factors, such as levels of fetal hemoglobin (HbF), the co-inheritance of alpha-thalassemia, or treatment with hydroxyurea.

METHODS

This cross-sectional study in children with sickle cell anemia evaluated bone age (BA), adult height prediction (AHP) using BA, a target height (TH) calculated as the mean SDS of the parents, and laboratory parameters. Children were grouped according to serum levels of HbF, co-inheritance of alpha-thalassemia, and hydroxyurea therapy.

RESULTS

The mean age of the 39 children was 8.2±2.2 years old. The average height was -0.75±0.30 SDS, and 10.3% (4/39) had short stature. Adjusted levels of IGF-1 or IGFBP-3 were significantly higher in children with sickle cell anemia on hydroxyurea treatment, in children with HbF levels >10%, and in those without alpha-thalassemia. Using SDS, the growth potential of children with sickle cell anemia in relation to their parents, calculated by the difference between AHP and TH, as well as the difference between children's height and their TH, were lower in children with co-inheritance of alpha-thalassemia Conclusion: The study showed an association between modifying factors and the GH/IGF-1 axis in children with sickle cell anemia. Additionally, the co-inheritance of alpha-thalassemia was associated with decreased height in these children when adjusted for their parents' height.

Inclusion and Withdrawal Criteria for Growth Hormone (GH) Therapy in Children with Idiopathic GH Deficiency—Towards Following the Evidence but Still with Unresolved Problems

According to current guidelines, growth hormone (GH) therapy is strongly recommended in children and adolescents with GH deficiency (GHD) in order to accelerate growth rate and attain normal adult height. The diagnosis of GHD requires demonstration of decreased GH secretion in stimulation tests, below the established threshold value. Currently, GHD in children is classified as secondary insulin-like growth factor-1 (IGF-1) deficiency. Most children diagnosed with isolated GHD present with normal GH secretion at the attainment of near-final height or even in mid-puberty. The most important clinical problems, related to the diagnosis of isolated GHD in children and to optimal duration of rhGH therapy include: arbitrary definition of subnormal GH peak in stimulation tests, disregarding factors influencing GH secretion, insufficient diagnostic accuracy and poor reproducibility of GH stimulation tests, discrepancies between spontaneous and stimulated GH secretion, clinical entity of neurosecretory dysfunction, discrepancies between IGF-1 concentrations and results of GH stimulation tests, significance of IGF-1 deficiency for the diagnosis of GHD, and a need for validation IGF-1 reference ranges. Many of these issues have remained unresolved for 25 years or even longer. It seems that finding solutions to them should optimize diagnostics and therapy of children with short stature.

Trends in insulin-like growth factor-1 levels after bariatric surgery: a systematic review and meta-analysis

According to studies, there are many inconsistencies in how IGF-1 levels change after bariatric surgery compared to before surgery, as well as its effects. These discrepancies can be attributed to various factors such as age, body mass index (BMI), and duration of intervention. Therefore, the aim of this study was to evaluate the level of insulin-like growth factor-1 (IGF-1) after bariatric surgery. A systematic review and meta-analysis based on the PRISMA guidelines was conducted from inception until 2021. From 1871 articles initially selected, 24 studies with 28 treatment arms met the eligible criteria and were included. Pooled findings from the random-effects model indicated that IGF-1 levels increased significantly [weighted mean difference (WMD) = 8.84 ng/ml; 95% confidence interval (CI) 0.30-17.39; p = 0.043] after bariatric surgery compared to before surgery. No significant heterogeneity was noted among the studies (Cochran Q test, p = 0.90, I² = 0.0%). In subgroup analysis, bariatric surgery significantly increased IGF-1 levels at age <40 years but not at age ≤40 years. Bariatric surgery is capable of increasing the IGF-1 levels compared to the period prior to surgery but with a modest clinical magnitude.

Leptin Does Not Influence TSH Levels in Obese Short Children

INTRODUCTION

Growth hormone (GH) and thyroid hormones are important for children growing. In some obese children a slightly elevated TSH concentration is observed. This may be an adaptive mechanism: stimulation of pro-TRH biosynthesis in the hypothalamus in response to elevated leptin. The increased TSH may also reflect the necessity of maintaining the resting energy expenditure or may be a result of inappropriate, low FT4 concentration. Thus, we evaluated serum TSH and FT4 concentrations in idiopathic short stature (ISS) children (non GH-deficient) and examined the effect of children's nutritional status and levels of selected adipocytokines on thyroid function, searching for the presence of various forms of subclinical hypothyroidism, which may be the cause of the slow growth rate.

METHODS

The study group included 115 children (50 girls and 65 boys) with ISS, aged (mean ± SD) 10.4 ± 3.34 years. In each child, lipids, TSH, FT4, IGF-1, maxGH during the stimulation tests, leptin, adiponectin and resistin concentrations were determined. Based on BMI SDS, 3 subgroups: slim (n=26), obese (n=21) and normal weight (n=68) were distinguished.

RESULTS

There was no correlation between leptin level and TSH, FT4 levels. The levels of leptin, total cholesterol and LDL-cholesterol in obese short children were significantly higher than in children from other subgroups. In turn, the levels of adiponectin, resistin, TSH and FT4 did not differ between subgroups. In 7% of children, an elevated TSH level was found (but less than 10 mIU/L), with a similar frequency across subgroups. The higher the leptin, the lower maxGH in clonidine stimulation test was recorded.

CONCLUSIONS

It seems that in obese children with idiopathic short stature leptin does not increase TSH secretion. This may be related to a disruption of the effect of leptin on TSH production and could indicate wide ranging disturbances of hypothalamic signals, and consequently be the cause of inappropriate GH secretion.

Modulation of PC1/3 activity by a rare double-site homozygous mutation

OBJECTIVES

Preprotein convertase 1/3 deficiency is a rare autosomal recessive disorder in which patients present with malabsorptive diarrhea and a series of symptoms of endocrine disorders such as polydipsia, reactive hypoglycemia, growth hormone deficiency, hypothyroidism, adrenal insufficiency, and early onset obesity. In its essence, pituitary hormone deficiency is caused by insufficient cleavage of pituitary prohormones. Here, we describe a female child with a rare double-site homozygous mutation in PCSK1 (Proprotein convertase subtilisin/kexin-type 1) gene, and thereby intend to investigate the relationship between these novel mutation sites and changes in protein synthesis and function.

METHODS

We tested this patient's blood and urine fecal indicators of infection, blood electrolytes, and relevant endocrine hormone levels in the laboratory. Next Generation Sequencing was applied to screen the patient's DNA. Western Blot was performed to evaluate the mutant protein's expression. The enzymatic activity was measured as the rate of cleavage of a synthetic fluorogenic substrate in a specific solution.

RESULTS

We found that this patient presented shortly after birth with uncorrectable diarrhea and symptoms of metabolic acidosis with hypothyroidism. Next Generation Sequencing revealed that a rare double-site homozygous missense mutation, c.763G > A (p.G255R) and c.758C > T (p.S253L), were detected in exon 7 of PCSK1 (Proprotein convertase subtilisin/kexin-type 1) gene on chromosome 5 of the patient. Western blotting revealed that there was no significant decrease in protein synthesis levels in the mutant phenotype compared to the wild type. Compared with WT type, the proteins expressed by the mutations showed a significant decrease in the enzyme activity towards the fluorescent substrates. However, neither the single site mutation p.S253L or p.G255R, nor the double-site mutation of both, all showed no significant differences from each other.

CONCLUSIONS

These two missense mutations have not been reported before, and it is even rarer to find homozygous variation of two sites in one patient. This study identifies two novel mutations for the first time and further investigates the changes in protein synthesis and enzyme activity, providing a new pathway to continue to explore the pathogenesis of diseases associated with the function of PC1/3.

Comparison of the effects of open vs. closed skill exercise on the acute and chronic BDNF, IGF-1 and IL-6 response in older healthy adults

BACKGROUND

Accumulating evidence shows that physical exercise has a positive effect on the release of neurotrophic factors and myokines. However, evidence regarding the optimal type of physical exercise for these release is still lacking. The aim of this study was to assess the acute and chronic effects of open-skill exercise (OSE) compared to closed-skill exercise (CSE) on serum and plasma levels of brain derived neurotrophic factor (BDNFS, BDNFP), and serum levels of insulin like growth factor 1 (IGF-1), and interleukin 6 (IL-6) in healthy older adults.

METHODS

To investigate acute effects, thirty-eight participants were randomly assigned to either an intervention (badminton (aOSE) and bicycling (aCSE), n  = 24, 65.83 ± 5.98 years) or control group (reading (CG), n  = 14, 67.07 ± 2.37 years). Blood samples were taken immediately before and 5 min after each condition. During each condition, heart rate was monitored. The mean heart rate of aOSE and aCSE were equivalent (65 ± 5% of heart rate reserve). In a subsequent 12-week training-intervention, twenty-two participants were randomly assigned to either a sport-games (cOSE, n  = 6, 64.50 ± 6.32) or a strength-endurance training (cCSE, n  = 9, 64.89 ± 3.51) group to assess for chronic effects. Training intensity for both groups was adjusted to a subjective perceived exertion using the CR-10 scale (value 7). Blood samples were taken within one day after the training-intervention.

RESULTS

BDNFS, BDNFP, IGF-1, and IL-6 levels increased after a single exercise session of 30 min. After 12 weeks of training BDNFS and IL-6 levels were elevated, whereas IGF-1 levels were reduced in both groups. However, only in the cOSE group these changes were significant. We could not find any significant differences between the exercise types.

CONCLUSION

Our results indicate that both exercise types are efficient to acutely increase BDNFS, BDNFP, IGF-1 and IL-6 serum levels in healthy older adults. Additionally, our results tend to support that OSE is more effective for improving basal BDNFS levels after 12 weeks of training.

Seventy eight children born small for gestational age without catch-up growth treated with growth hormone from the prepubertal stage until adult height age. An evaluation of puberty and changes in the metabolic profile

A wide variation in height gain rate is observed in children small for gestational age (SGA) treated with growth hormone (GH). The aim of this study was to evaluate prepubertal and pubertal growth, height gain attained at adult age and to assess potential predictive factors in catch-up growth. Changes in metabolic profile were also analyzed.

PATIENTS AND METHODS

Seventy-eight children born SGA were treated with a GH median dose of 33.0±2.8mcg/kg/day at a mean age of 7.3±2.0 (boys) and 6.0±1.8 (girls).

RESULTS

Mean height (SDS) at GH onset was -3.31±0.7 for boys and -3.48±0.7 for girls. According to age at pubertal growth spurt onset patients were classified in their pubertal maturity group. Adult height attained expressed in SDS was -1.75±0.7 for boys and -1.69±1.0 for girls, both below the range of their mid-parental height. The greatest height gain occurred during the prepubertal period. Patients with greater height gain were lighter (p<0.001), shorter (p=0.005), and younger (p=0.02) at the start of GH, and also showed a greater increase in growth velocity during the first year on GH (p<0.001). SGA children started puberty at the same age and with the same distribution into pubertal maturity group as the reference population. No relevant GH-related adverse events were reported, including in the insulin resistance parameters evaluated. Differences were found in fasting plasma glucose values, but were without clinical relevance. IGF-I plasma values remained within the safety range.

CONCLUSIONS

GH therapy is safe and beneficial for SGA children. The response to GH therapy is widely heterogeneous, suggesting that GH should be started at a young age and the GH dose prescribed should be individualized. SGA children started puberty at the same age as the reference population. The only factor that predicts greater adult height is growth velocity during the first year of therapy.

Effects of raloxifene administration on serum levels of insulin-like growth factor-1 and insulin-like growth factor-binding protein 3 levels: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To ascertain the clinical magnitude of raloxifene administration on insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-binding protein 3 (IGFBP-3) levels.

METHODS

A systematic comprehensive search was performed without language limitation up to 14 December 2020. We included only trials that assessed the effect of raloxifene on IGF-1 and IGFBP-3 in adults. Meta-analysis was performed using the Stata software (Stata Corp. College Station, Texas, USA).

RESULTS

Seven arms were included, encompassing postmenopausal women with type 2 diabetes mellitus, postmenopausal women with breast cancer, healthy postmenopausal women, and healthy elderly men. Raloxifene therapy significantly reduced IGF-1 levels (WMD: -2.92 nmol/L, 95% CI: -3.49, -2.35, p < 0.001) compared to placebo. Raloxifene dosage ˃60 mg/day (WMD: -3.29 ng/mL, 95% CI: -3.50 to -3.08, I² = 0.0%) decreased IGF-1 levels more than 60 mg/day (WMD: -2.29 ng/mL, 95% CI: -2.90 to -1.69, I² = 16%). Moreover, intervention duration ˃26 weeks (WMD: -3.48 ng/mL, 95% CI: -5.26 to -1.69, I² = 0.0%) reduced IGF-1 levels more than ˂26 weeks (WMD: -2.55 ng/mL, 95% CI: -3.31 to -1.79, I² = 92%). In contrast, overall results from the random-effects model did not suggest a significant change in IGFBP-3 levels upon raloxifene therapy.

CONCLUSION

Raloxifene therapy significantly reduced serum levels of IGF-1 levels but without changes in IGFPB-3 levels.

Comparison of the difference in serum insulin growth factor-1 levels between chronological age and bone age among children

OBJECTIVE

By measuring serum insulin-like growth factor-1 (IGF-1) levels in children aged 2-16, we aimed to analyze the changes in IGF-1 levels in different sex and age groups, and compare the consistency of IGF-1 results evaluated by chronological age (CA) and bone age (BA) in children.

METHODS

A cross-sectional study was conducted between January 2017 and December 2020 among 2979 relatively healthy children who attended the Department of Growth and Development outpatient clinic and health care center of the Affiliated Children's Hospital of the Capital Institute of Pediatrics and underwent health examination and development assessment. Height, weight, and Tanner pubertal stage were measured by pediatricians. The CHN method was used to estimate BA. Venous blood samples were collected from the children, and IGF-1 levels were determined via chemiluminescence.

RESULTS

IGF-1 levels in childhood increased slowly with age, dramatically during puberty,and continuously withgrowth until to 15 years for boys and reached a peak value at 13 years for girls based on CA. IGF-1 levels reached peak values at 14 and 13 years for boys and girls, respectively, based on BA. There were differences in IGF-1 values between the CA and BA groups at the age of 10-11 years for boys and 7-11 years for girls. A total of 103 boys (7.7%) and 17 girls (1.0%) had IGF-1 levels below the lower limit of the reference range based on CA; evaluating based on BA, there were 82 boys (6.1%) and 15 girls (0.9%) still had IGF-1 values less than the lower limit of the reference range. Eighteen boys (1.3%) and 173 girls (10.5%) had IGF-1 levels above the upper limit of the reference range based on CA; evaluating based on BA, these numbers reduced to 5 (0.4%) among boys and 41 (2.5%) among girls.

CONCLUSIONS

There is a significant difference between BA and CA in evaluating IGF-1 levels in children, which can significantly reduce the proportion of IGF-1 values above the upper limit of the kit reference range in children. This suggests that children with BA advanced in pubertal period, the evaluating results of IGF-1 should be corrected by using BA.

A Bayesian Approach to Diagnose Growth Hormone Deficiency in Children: Insulin-Like Growth Factor Type 1 Is Valuable for Screening and IGF-Binding Protein Type 3 for Confirmation

BACKGROUND

The utility of insulin-like growth factor type 1 (IGF-1) is well established in the diagnosis of growth hormone deficiency (GHD), whereas IGF-binding protein type 3 (IGFBP-3) has a more controversial role. Most studies evaluated the value of these peptides by assessing their sensitivity and specificity but not considering the low prevalence of GHD among short children (<2%).

OBJECTIVE

To evaluate the utility of basal IGF-1 and IGFBP-3 values in the GHD diagnosis process with a Bayesian approach, based on pre- and post-test probability.

METHODS

We determined ROC curves, sensitivity, specificity, and positive and negative predictive values for IGF-1 and IGFBP-3 obtained from patients with GHD (n = 48) and GH-sufficient children (n = 175). The data were also analyzed by classifying the children into early childhood and late childhood (girls and boys younger and older than 8 and 9 years, respectively).

RESULTS

The area under the curve (AUC) of the receiver operating characteristic curve of IGF-1-SDS (standard deviation score) was greater than that of IGFBP-3-SDS (AUC 0.886 and 0.786, respectively, p = 0.001). In early childhood, the AUC of IGFBP-3-SDS was significantly improved (0.866) and similar to IGF-1-SDS (0.898). IGF-1-SDS, in comparison to IGFBP-3-SDS, had a greater sensitivity (92 vs. 45.8%, respectively), lower specificity (69 vs. 93.8%, respectively), and lower positive predictive value (5.7 vs. 13.1%, respectively), with similar negative predictive values.

CONCLUSION

IGF-1-SDS is a useful screening tool in the diagnosis of GHD. Although IGFBP-3-SDS lacks sensitivity, its high specificity supports the role to confirm GHD in short children, especially in early childhood. This strategy could simplify and reduce the necessity of a second laborious and expensive GH stimulation test to confirm the diagnosis of GHD.

Insulin-like Growth Factor 1, but Not Insulin-Like Growth Factor-Binding Protein 3, Predicts Central Precocious Puberty in Girls 6-8 Years Old: A Retrospective Study

BACKGROUND

Central precocious puberty (CPP) in females is characterized by thelarche before 8 years of age. Evidence of reproductive axis activation confirms the diagnosis (basal serum luteinizing hormone (LH) ≥0.3 IU/L or LH-releasing hormone (LHRH)-stimulated LH ≥5 IU/L). Stimulation testing is the diagnostic gold standard but is time-consuming and costly. Serum levels of insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-binding protein 3 (IGFBP-3) are increased in girls with CPP.

OBJECTIVE

The aim of the study was to assess the utility of serum IGF-1 and IGFBP-3 in identifying CPP in girls aged 6-8 years.

METHODS

The study was a single-center retrospective study. Girls with confirmed CPP (n = 44) and isolated premature precocious adrenarche/ precocious thelarche (PA/PT, n = 16) had baseline biochemical profiling and LHRH stimulation testing. Serum IGF-1 and IGFBP-3 results were converted to standard deviation scores (SDS). Correlations were calculated and receiver operating characteristic curves were plotted.

RESULTS

Girls with CPP had higher basal and peak LH, IGF-1 SDS, and growth velocity (p < 0.05). IGF-1 SDS correlated positively with basal and peak LH (p < 0.05). IGF-1 SDS (1.75-2.15) differentiated CPP and PA/PT with 89% sensitivity and 56% specificity (basal LH) and 94% specificity and 55% sensitivity (peak LH). IGFBP-3 SDS did not differ between groups or by CPP parameters.

CONCLUSIONS

In clinical practice, IGF-1 SDS may be an additional tool for identifying CPP in girls aged 6 to 8 years when baseline clinical and laboratory diagnostic criteria are inconclusive, possibly avoiding more time-consuming and costly procedures.

Seventy eight children born small for gestational age without catch-up growth treated with growth hormone from the prepubertal stage until adult height age. An evaluation of puberty and changes in the metabolic profile

A wide variation in height gain rate is observed in children small for gestational age (SGA) treated with growth hormone (GH). The aim of this study was to evaluate prepubertal and pubertal growth, height gain attained at adult age and to assess potential predictive factors in catch-up growth. Changes in metabolic profile were also analyzed.

PATIENTS AND METHODS

Seventy-eight children born SGA were treated with a GH median dose of 33.0±2.8mcg/kg/day at a mean age of 7.3±2.0 (boys) and 6.0±1.8 (girls).

RESULTS

Mean height (SDS) at GH onset was -3.31±0.7 for boys and -3.48±0.7 for girls. According to age at pubertal growth spurt onset patients were classified in their pubertal maturity group. Adult height attained expressed in SDS was -1.75±0.7 for boys and -1.69±1.0 for girls, both below the range of their mid-parental height. The greatest height gain occurred during the prepubertal period. Patients with greater height gain were lighter (p<0.001), shorter (p=0.005), and younger (p=0.02) at the start of GH, and also showed a greater increase in growth velocity during the first year on GH (p<0.001). SGA children started puberty at the same age and with the same distribution into pubertal maturity group as the reference population. No relevant GH-related adverse events were reported, including in the insulin resistance parameters evaluated. Differences were found in fasting plasma glucose values, but were without clinical relevance. IGF-I plasma values remained within the safety range.

CONCLUSIONS

GH therapy is safe and beneficial for SGA children. The response to GH therapy is widely heterogeneous, suggesting that GH should be started at a young age and the GH dose prescribed should be individualized. SGA children started puberty at the same age as the reference population. The only factor that predicts greater adult height is growth velocity during the first year of therapy.

Anthropometric, biochemical and hormonal profiles of the partially admixed pygmoid group in Rampasasa (Flores, Indonesia)

OBJECTIVES

We performed a cross-sectional study on anthropometric and laboratory characteristics of inhabitants of Rampasasa (Flores, Indonesia). Adults were categorised according to ancestry into three groups: pygmoid (P/P, offspring of pygmoid parents, n=8), mixed pygmoid (P/N, offspring of pygmoid and non-pygmoid parents, n=12) and non-pygmoid (N/N, n=10). Children (n=28) were P/N.

METHODS

Measurements included height, weight, sitting height, arm span, head circumference, haematological analysis and serum albumin, calcium, vitamin D, insulin-like growth factor-I (IGF-I) and IGF binding protein 3 (IGFBP-3). Pubertal stage and bone age was assessed in children. Anthropometric data were expressed as standard deviation score (SDS) for age. IGF-I, IGFBP-3 and IGF-I/IGFBP-3 ratio were expressed as SDS for age, bone age and pubertal stage.

RESULTS

Mean height SDS showed a gradient from P/P (-4.0) via P/N (-3.2) to N/N (-2.3) (-3.4, -3.1 and -2.2 adjusted for age-associated shrinking). Sitting height and head circumference showed similar gradients. Serum IGF-I SDS was similar among groups (approximately -1 SDS). IGFBP-3 SDS tended toward a gradient from P/P (-1.9) via P/N (-1.5) to N/N (-1.1), but IGF-I/IGFBP-3 ratio was normal in all groups. In P/P and P/N, mean head circumference SDS was >2 SD greater than mean height SDS. Children showed a progressive growth failure and bone age delay, delayed female pubertal onset and an initial low serum IGF-I, normal IGFBP-3 and low IGF-I/IGFBP-3 ratio.

CONCLUSIONS

P/P showed proportionate short stature with relative macrocephaly and relatively low IGFBP-3; P/N presented an intermediate pattern. P/N children were progressively short, showed delayed skeletal maturation, delayed puberty in girls and low IGF-I and IGF-I/IGFBP-3.

Safety and effectiveness of Omnitrope® in patients with growth hormone deficiency: snapshot analysis of PATRO Adults study in the Italian population

PURPOSE

PATRO adults is an ongoing, multicenter, observational, post-marketing surveillance study aimed at investigating the long-term safety (primary endpoint) and effectiveness (secondary endpoint) of the recombinant human growth hormone (rhGH) Omnitrope® during routine clinical practice. This report describes data from Italian participants in PATRO Adults with growth hormone deficiency (GHD), up to August 2017.

METHODS

Participants were adults (aged > 18 years) with GHD requiring rhGH therapy and were prescribed Omnitrope®, including those who had previously received another rhGH product. Adverse events (AEs) were evaluated in all study participants. Data were collected on insulin-like growth factor (IGF)-I levels and cardiovascular risk factors, including blood pressure, lipids, and anthropometric parameters.

RESULTS

From September 2007 to August 2017, 88 patients (mean age 48.9 years, 58.0% male) were enrolled at 8 sites in Italy. The mean treatment duration with Omnitrope® was 51.5 ± 37 months. AEs occurred in 54 patients; the most common were asthenia (20.5%), headache (14.8%), and arthralgia (13.6%). Serious AEs occurred in 22 patients (25%), including pneumonia (n = 2) and renal failure (n = 2). Neoplasms (2 benign and 1 malignant) developed in three patients, but none were considered to be drug-related. There were no significant changes in fasting glucose or glycosylated hemoglobin (HbA1c) during the study period. Long-term Omnitrope® therapy showed slight positive effects on lipid profile, while no significant changes were observed in body weight and BMI during the study.

CONCLUSION

This snapshot analysis of Italian participants in PATRO Adults confirmed the long-term safety and effectiveness of Omnitrope® in adults with GHD.

Robotic Radiosurgery for Persistent Postoperative Acromegaly in Patients with Cavernous Sinus-Invading Pituitary Adenomas-A Multicenter Experience

Simple Summary

Growth hormone-secreting tumors of the pituitary gland which infiltrate surrounding tissue structures may not be fully resectable. This causes many patients to suffer from acromegaly after an unsuccessful surgery. To limit the considerable morbidity and mortality of such patients, effective and safe treatment options are needed. Fractionated radiotherapy and growth hormone-lowering medication are possible treatment options. Robotic radiosurgery (RRS) may be a suitable treatment modality as well. However, only sparse and heterogeneous data are available. This first retrospective multicenter study investigated the efficacy and safety of RRS for this patient group. Outcomes provide evidence that RRS may achieve biochemical disease control or remission in most of the patients. The hormone levels are decreasing after treatment, whereas favorable risk and safety profiles of RRS were shown. No new tumor growth was observed throughout the available follow-up. These findings may guide future care for this challenging patient population.

Abstract

Background: The rates of incomplete surgical resection for pituitary macroadenomas with cavernous sinus invasion are high. In growth hormone-producing adenomas, there is a considerable risk for persistent acromegaly. Thus, effective treatment options are needed to limit patient morbidity and mortality. This multicenter study assesses the efficacy and safety of robotic radiosurgery (RRS) for patients with cavernous sinus-invading adenomas with persistent acromegaly. Methods: Patients who underwent RRS with CyberKnife for postoperative acromegaly were eligible. Results: Fifty patients were included. At a median follow-up of 57 months, the local control was 100%. The pretreatment insulin-like growth factor 1 (IGF-1) levels and indexes were 381 ng/mL and 1.49, respectively. The median dose and prescription isodose were 18 Gy and 70%, respectively. Six months after RRS, and at the last follow-up, the IGF-1 levels and indexes were 277 ng/mL and 1.14, as well as 196 ng/mL and 0.83, respectively (p = 0.0001 and p = 0.0002). The IGF-1 index was a predictor for biochemical remission (p = 0.04). Nine patients achieved biochemical remission and 24 patients showed biochemical disease control. Three patients developed a new hypopituitarism. Conclusions: RRS is an effective treatment for this challenging patient population. IGF-1 levels are decreasing after treatment and most patients experience biochemical disease control or remission.

Long-term follow up of carbohydrate metabolism and adverse events after termination of Omnitrope® treatment in children born small for gestational age

BACKGROUND

Recombinant human growth hormone (rhGH) therapy can affect carbohydrate metabolism and lead to impaired glucose tolerance during treatment. In addition, short children born small for gestational age (SGA) are predisposed to metabolic abnormalities. This study assessed the long-term safety of rhGH (Omnitrope®) use in short children born SGA.

METHODS

This was a follow-up observational study of patients from a phase IV study. The baseline visit was the final visit of the phase IV study. Further visits were planned after 6 months (F1), 1 year (F2), 5 years (F3), and 10 years (F4). The primary objective was to evaluate the long-term effect of rhGH treatment on the development of diabetes mellitus; secondary objectives included incidence/severity of adverse events (AEs).

RESULTS

In total, 130 subjects were enrolled in the follow-up study; 99 completed F1, 88 completed F2, and 13 completed F3 (no subject reached F4). The full analysis set for evaluation comprised 118 patients (64 female). Mean (standard deviation) duration of follow up was 39.6 (24.4) months. No subject was newly diagnosed with diabetes. The results for carbohydrate metabolism parameters were consistent with this finding. A total of 144 AEs were reported in 54 subjects; these were mostly of mild-to-moderate intensity (96.5%) and not suspected to be related to previous rhGH treatment (94.4%). Serious AEs (n = 18) were reported in eight patients; three (in one patient) were suspected as possibly related to previous rhGH treatment (anemia, menorrhagia, oligomenorrhoea). One fatal event occurred (sepsis), which was judged as not related to previous rhGH treatment.

CONCLUSIONS

None of the participating subjects, who had all been previously treated with Omnitrope® in a phase IV study, developed diabetes during this follow-up study. In addition, no other unexpected or concerning safety signals were observed.

The effects of lycopene supplementation on serum insulin-like growth factor 1 (IGF-1) levels and cardiovascular disease: A dose-response meta-analysis of clinical trials

BACKGROUND

The results of human studies assessing the efficacy of lycopene on insulin-like growth factor 1 (IGF-1) levels are inconsistent. Thus, we performed a systematic review and meta-analysis to examine the effects of lycopene supplementation on serum IGF-1 levels and cardiovascular disease.

METHODS

The literature published up to January 2020 was searched using the electronic databases Scopus, PubMed/Medline, Web of Science, Embase and Google Scholar.

RESULTS

Seven qualified trials were included in the current meta-analysis. IGF-1 levels were non-significantly decreased in lycopene group compared to the control (WMD: -6.74 ng/mL, 95 % CI: -23.01 to 9.52, p = 0.42; I² = 94.3 %). Subgroup analysis revealed a significantly decrease in IGF-1 levels upon lycopene supplementation at doses ≥15 mg/d (WMD: -6.40 ng/mL), intervention period <12 weeks (WMD: -6.49 ng/mL), and subjects aged ≥60 years (WMD: -24.98 mg/dl). In addition, lycopene intake significantly reduced IGF-1 levels upon healthy conditions (WMD: -25.59 ng/mL) when compared with cancer patients (WMD: 0.35 ng/mL). In addition, the effect of lycopene supplementation was significant in patients diagnosed with cardiac disorders.

CONCLUSION

Overall, lycopene intake was not associated with reduced serum IGF-1 levels. However, association was significant when lycopene was administrated at doses >15 mg/d, for <12 weeks, as well as for healthy conditions and patients aged ≥60 years. In addition, lycopene supplementation exhibited potential health benefits in the management of patients with cardiac disorders.

IGF1 for the diagnosis of growth hormone deficiency in children and adolescents: a reappraisal

A number of studies have evaluated the role of IGF1 measurement in the diagnosis of growth hormone deficiency (GHD). This study aimed to evaluate the accuracy and the best cut-off of IGF1 SDS in the diagnosis of GHD in a large cohort of short children and adolescents. One-hundred and forty-two children and adolescents with GHD ((63 organic/genetic (OGHD), 79 idiopathic (IGHD)) and 658 short non-GHD children (median age 10.4 years) were included in the analysis. The two groups were subdivided according to age (G1 <6, G2 6 <9, G3 9 <12, G4 ≥12) and to pubertal status. Serum IGFI was measured by the same chemiluminescence assay in all samples and expressed as age- and sex-based SDS. Receiver operating characteristic (ROC) analysis was used to evaluate the optimal IGF1 SDS cut-off and the diagnostic accuracy. Median IGF1 SDS was significantly lower in the GHD than in non-GHD patients. The area under the curve (AUC) was 0.69, with the best IGF1 cut-off of -1.5 SDS (sensitivity 67.61%, specificity 62.62%). The AUC was 0.75 for OGHD and 0.63 for IGHD. The accuracy was better in the pubertal (AUC = 0.81) than the prepubertal group (AUC = 0.64). In our cohort, IGF1 measurement has poor accuracy in discriminating GHD from non-GHD. Our findings confirm and reinforce the belief that IGF1 values should not be used alone in the diagnosis of GHD but should be interpreted in combination with other clinical and biochemical parameters.

Comparison of nocturnal and morning ghrelin concentration in children with growth hormone deficiency and with idiopathic short stature

Ghrelin - a growth hormone (GH) secretagogue - presents a circadian rhythm with higher nocturnal than diurnal concentration (similar to GH). However, daily ghrelin production depends on food intake and nutritional state; it is increased in the fasting state and decreased after a meal. Since most past research concerning short stature children has relied on the morning ghrelin concentration for analyses, we decided to assess ghrelin concentration at the 60^th and 90^th minute after falling asleep and in the morning at 06:00 h, shortly after waking up from nighttime sleep (after 12 h of fasting). We compared these ghrelin concentrations to determine differences between nocturnal and morning ghrelin release in short children, both with idiopathic short stature (ISS) and growth hormone deficiency (GHD). We also analyzed the correlation between the nocturnal and morning ghrelin concentrations with nocturnal GH concentrations, measured at the same time points, as well as with maximal GH concentration, achieved by stimulation tests, and with the insulin-like growth factor I (IGF-I). The ghrelin and GH concentration 60^th and 90^th minute after falling asleep, as well as fasting morning ghrelin and IGF-I concentrations, were measured in 19 (n = 10 ISS and n = 9 GHD) prepubertal short children (7 girls and 12 boys), aged 10.36 ± 3.06 y. Differences between the nocturnal and morning ghrelin concentrations were analyzed by the Wilcoxon matched-pairs signed-rank test. Typical regression and correlation analyses were used to assess relationships among parametric data for other analyses. The Wilcoxon test showed ghrelin concentration is significantly higher in the morning than both at the 60^th and 90^th minute after falling asleep time points (in ISS and GHD). A significant correlation was observed: a) positive - between nocturnal ghrelin (both at the 60^th and 90^th minute) and morning ghrelin concentrations; b) positive - between ghrelin at the 60^th minute and nocturnal GH concentrations (both at the 60^th and 90^th minute); c) negative - between ghrelin at the 60^th minute and IGF-I concentrations; and d) negative - between body mass index and ghrelin concentrations at the 60^th and 90^th minute. We conclude: 1) in short children, both with GHD and with ISS, morning ghrelin level reflects its nocturnal concentration; however, it is significantly higher than the nocturnal ones. There is no significant difference between the measurement of ghrelin concentration at night at the 60^th or 90^th minute after falling asleep; 2) morning ghrelin concentration is affected by the hunger and satiety; therefore, it appears that nocturnal measurements better reflect the pool of hormone responsible for stimulation of GH and IGF-I secretion, especially since positive correlation between nocturnal ghrelin and nocturnal GH secretion was noted; 3) it seems that a higher body mass index is an additional independent factor, associated mainly with lower nocturnal (but not morning) ghrelin secretion.

An Intense, But Ecologically Valid, Resistance Exercise Session Does Not Alter Growth Factors Associated With Cognitive Health

The purpose of this investigation was to assess the acute changes in growth factors associated with cognitive health following two ecologically valid, intense resistance exercise sessions. Twenty-nine late-middle-aged adults performed one session of either (a) moderate-load resistance exercise or (b) high-load resistance exercise. Venous blood was collected prior to warm-up, immediately following exercise and 30 min following exercise. Serum was analyzed for brain-derived neurotrophic factor, insulin-like growth factor 1, and vascular endothelial growth factor. Session intensity was determined by blood lactate concentration and session rating of perceived exertion. Postexercise blood lactate was greater following moderate-load when compared with high-load resistance exercise. Subjective session intensity was rated higher by the session rating of perceived exertion following moderate-load when compared with high-load resistance exercise. No differences were observed in serum growth factor levels between groups. Ecologically valid and intense moderate-load or high-load exercise methods do not alter serum growth factor levels in late-middle-aged adults.

A Proposal for the Interpretation of Serum IGF-I Concentration as Part of Laboratory Screening in Children with Growth Failure

The serum insulin-like growth factor-I (IGF-I) concentration is commonly used as a screening tool for growth hormone deficiency (GHD), but there is no consensus on the cut-off limit of IGF-I standard deviation score (SDS) to perform GH stimulation tests for confirmation or exclusion of GHD. We argue that the cut-off limit is dependent on the clinical pre-test likelihood of GHD and propose a diagnostic strategy in which the cut-off limit varies between zero to -2 SDS.

Growth and Clinical Characteristics of Children with Floating-Harbor Syndrome: Analysis of Current Original Data and a Review of the Literature

BACKGROUND

Floating-Harbor syndrome (FHS) is a rare condition characterized by dysmorphic facial features, short stature, and expressive language delay.

OBJECTIVE

The aim of this study was to describe a cohort of patients with FHS and review the literature about the response to recombinant human growth hormone (rhGH) therapy.

METHODS

Anthropometric and laboratory data from 7 patients with FHS were described. The molecular diagnosis was established by multigene analysis. Moreover, we reviewed the literature concerning patients with FHS treated with rhGH.

RESULTS

All 7 patients were born small for gestational age. At first evaluation, 6 patients had a height standard deviation score (SDS) ≤-2 and 1 had short stature in relation to their target height. Bone age was usually delayed, which rapidly advanced during puberty. Nonspecific skeletal abnormalities were frequently noticed, and normal to elevated plasma IGF-I levels were observed in all except 1 patient with growth hormone deficiency. Information about 20 patients with FHS treated with rhGH was analyzed (4 from our cohort and 16 from the literature). The median height changes during the treatment period (approx. 2.9 years) were 1.1 SDS (range from -0.4 to 3.1). Nontreated patients had an adult height SDS of -4.1 ± 1.2 (n = 10) versus -2.6 ± 0.8 SDS (n = 7, p 0.012) for treated patients.

CONCLUSION

We observed a laboratory profile compatible with IGF-1 insensitivity in some patients with FHS. Nevertheless, our study suggests that children with FHS may be considered as candidates for rhGH therapy. Further studies are necessary to establish the real benefit and safety of rhGH therapy in these patients.

Impact of dehydroepianrosterone (DHEA) supplementation on serum levels of insulin-like growth factor 1 (IGF-1): A dose-response meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Inconsistencies exist with regard to the influence of dehydroepiandrosterone (DHEA) supplementation on insulin-like growth factor 1 (IGF-1) levels. The inconsistencies could be attributed to several factors, such as dosage, gender, and duration of intervention, among others. To address these inconsistencies, we conducted a systematic review and meta-analysis to combine findings from randomized controlled trials (RCTs) on this topic.

METHODS

Electronic databases (Scopus, PubMed/Medline, Web of Science, Embase and Google Scholar) were searched for relevant literature published up to February 2020.

RESULTS

Twenty-four qualified trials were included in this meta-analysis. It was found that serum IGF-1 levels were significantly increased in the DHEA group compared to the control (weighted mean differences (WMD): 16.36 ng/ml, 95% CI: 8.99, 23.74; p = .000). Subgroup analysis revealed that a statistically significant increase in serum IGF-1 levels was found only in women (WMD: 23.30 ng/ml, 95% CI: 13.75, 32.87); in participants who supplemented 50 mg/d DHEA (WMD: 15.75 ng/ml, 95% CI: 7.61, 23.89); in participants undergoing DHEA intervention for >12 weeks (WMD: 17.2 ng/ml, 95% CI: 8.02, 26.22); in participants without an underlying comorbidity (WMD: 19.11 ng/ml, 95% CI: 10.69, 27.53); and in participants over the age of 60 years (WMD: 19.79 ng/ml, 95% CI: 9.86, 29.72).

CONCLUSION

DHEA supplementation may increase serum IGF-I levels especially in women and older subjects. However, further studies are warranted before DHEA can be recommended for clinical use.

Pathogenic/likely pathogenic variants in the SHOX, GHR and IGFALS genes among Indian children with idiopathic short stature

Background Our objective was to estimate the prevalence of pathogenic/likely pathogenic variants in the SHOX, GHR, and IGFALS genes among Indian children with idiopathic short stature (ISS), and assess the genotype-phenotype correlation. Methods We recruited 61 children with short stature, who were born appropriate for gestational age, had no obvious dysmorphism or disproportion, and in whom step-wise investigative work-up (including provocative growth hormone test) was normal. Multiplex ligation-dependent probe amplification was undertaken for identifying deletions/duplications in the SHOX gene. Bidirectional sequencing was performed for identifying variants in the SHOX and GHR genes in all, and for the IGFALS gene in those with serum insulin-like growth factor-1 (IGF-1) <-1 standard deviation. The genotype-phenotype correlation was studied. Results Four children (6.5%) had pathogenic heterozygous variants in the SHOX gene, with one child each having duplication of exon 5, splice site point variant c.278-1G > C in exon 3, partial deletion and complete deletion. None of the patients had pathogenic variants in the GHR gene. Of the 39 patients in whom the IGFALS gene was sequenced, novel heterozygous likely pathogenic variants were found in two children. One had the frameshift variant c.764_765insT, p.A265Gfs*114. The second had the missense variant c.1793G > A, p.R598H predicted by MutationTaster as 'disease causing', and indicated by the protein-modelling study as having compromised binding with IGF-1 and insulin-like growth factor binding protein-3 (IGFBP-3) due to altered conformation of the interacting loop. Conclusions Pathogenic variants in the SHOX and IGFALS genes account for a significant proportion of Indian children with ISS. Further molecular studies using next generation sequencing are needed to gain insight into pathophysiological mechanisms and effective treatment strategies for ISS.

Significance of Direct Confirmation of Growth Hormone Insensitivity for the Diagnosis of Primary IGF-I Deficiency

Primary insulin-like growth factor-I (IGF-I) deficiency is a synonym of growth hormone (GH) insensitivity (GHI), however the necessity of direct confirmation of GH resistance by IGF-I generation test (IGF-GT) is discussed. GHI may disturb intrauterine growth, nevertheless short children born small for gestational age (SGA) are treated with GH. We tested the hypothesis that children with appropriate birth size (AGA), height standard deviation score (SDS) <−3.0, GH peak in stimulation tests (stimGH) ≥10.0 µg/L, IGF-I <2.5 centile, and excluded GHI may benefit during GH therapy. The analysis comprised 21 AGA children compared with 6 SGA and 20 GH-deficient ones, with height SDS and IGF-I as in the studied group. All patients were treated with GH up to final height (FH). Height velocity, IGF-I, and IGF binding protein-3 (IGFBP-3) concentrations before and during first year of treatment were assessed. Effectiveness of therapy was better in GHD than in IGF-I deficiency (IGFD), with no significant difference between SGA and AGA groups. All but two AGA children responded well to GH. Pretreatment IGF-I and increase of height velocity (HV) during therapy but not the result of IGF-GT correlated with FH. As most AGA children with apparent severe IGFD benefit during GH therapy, direct confirmation of GHI seems necessary to diagnose true primary IGFD in them.

GH-IGF-1 Axis in Children with Cystic Fibrosis

OBJECTIVE

To verify whether growth hormone receptor (GHR) gene expression plays a role in growth of children with cystic fibrosis (CF), as a consequence of the chronic inflammatory condition and malnutrition.

DESIGN

We enrolled 49 prepubertal patients (24 males and 25 females) affected by CF in a stable clinical condition, 19 of whom had been diagnosed through newborn screening and 30 following presentation of symptoms. Patients had no significant comorbidity affecting growth or cystic fibrosis transmembrane conductance regulator (CFTR)-related diabetes requiring insulin therapy. Blood was collected during two follow-up visits to measure insulin-like growth factor (IGF-I), growth hormone-binding protein (GHBP), and GHR gene expression. Recruited as a control group were 52 healthy children, sex- and age-matched, were recruited as a control group.

METHODS

We compared body mass index (BMI), height, weight, IGF-I, GHBP, and GHR gene expression values (evaluated by Chemiluminescent Immunometric assay; ELISA and real-time PCR, respectively) in CF patients diagnosed through newborn screening (NBS) or by symptoms (late diagnosis [LD]) and in healthy controls.

RESULTS

BMI increased significantly in patients between the time of diagnosis and check-up (P<0.001), particularly in the LD group; median value was lower at diagnosis and significantly higher (P<0.001) at follow-up visits compared to controls. At initial evaluation, higher levels of IGF-I (not statistically significant) were found in both the NBS group and the LD group compared to the control group. At the second evaluation, significantly higher levels of IGF-I (P=0.003) were found in both the NBS and LD groups compared to controls; GHR mRNA expression had significantly increased (P=0.013) in LD patients compared with the first evaluation and was significantly higher in the NBS and LD groups than in controls. GHBP values had significantly increased (P=0.047) in the NBS group after one year of therapy compared to first visit levels and were significantly higher (P<0,0001) in the NBS and LD groups compared to controls.

CONCLUSION

In our LD patients during childhood, we observed good auxological values and a GH/IGF-I axis function within normal range for the factor evaluated. However, earlier diagnosis through NBS might further minimize and prevent growth retardation, by reducing the duration of symptoms before treatment.

Laboratory investigations in the diagnosis and follow-up of GH-related disorders

In addition to auxiological, clinical and metabolic features measurements of growth hormone (GH) and insulin-like growth factor I (IGF-I) complement our tools in diagnosis and follow-up of GH-related disorders. While comparably robust during the pre-analytical phase, measurement and interpretation of concentrations of both hormones can be challenging due to analytical issues and biological confounders. Assay methods differ in terms of antibody specificity, interference from binding proteins, reference preparations and sensitivity. GH assays have different specificity towards different GH-isoforms (e.g. 20 kDa GH, placental GH) and interference from the GH antagonist Pegvisomant. The efficacy to prevent binding protein interference is most important in IGF-I assays. Methodological differences between assays require that reference intervals and diagnostic cut-offs are assay-specific. Among biological variables, pubertal development and age are most relevant for IGF-I, making detailed reference intervals mandatory for interpretation. GH has pulsatile secretion and short half-life. Its concentration is modified by acute factors such as stress, exercise and sleep, but also by intake of oral estrogens and anthropometric factors (e.g. BMI). Other GH dependent biomarkers such as free IGF-I, IGF binding protein 3 (IGFBP 3) and acid labile subunit (ALS) have been proposed. Their concentrations largely mirror the information obtained through measurement of IGF-I, but their measurement can be helpful in particular situations. In this review, we describe the evolution of analytical methods to measure biomarkers of GH action, the impact of the methodological changes on laboratory results and the need to include biological variables in their interpretation. Arch Endocrinol Metab. 2019;63(6):618-29.

A New Case of PCSK1 Pathogenic Variant With Congenital Proprotein Convertase 1/3 Deficiency and Literature Review

ISSUE

To report a homozygous pathogenic variant in PCSK1 in a boy affected with proprotein convertase 1/3 (PC1/3) deficiency.

CASE DESCRIPTION AND LITERATURE REVIEW

A male infant born to consanguineous Turkish parents presented in the first week of life with transient central diabetes insipidus, watery diarrhea, micropenis due to hypogonadotropic hypogonadism and GH deficiency, and transient asymptomatic hypoglycemia. Further endocrine defects gradually appeared, including central hypothyroidism and mild central hypocortisolism (at 1 year), central diabetes insipidus that reappeared progressively (at 2.5 years), and obesity (at 2 years). Whole-exome sequencing revealed a homozygous nonsense pathogenic variant (NM_000439.4) c. 595 C>T in exon 5 of PCSK1, not yet reported in cases of PC1/3 deficiency. To date, 26 cases of PC1/3 deficiency have been reported in the literature. All individuals had early and severe malabsorptive diarrhea and 83% had polyuria-polydipsia syndrome (before 5 years). Most (79%) had early onset obesity. Various endocrine disorders were present, including GH deficiency (44%), mild central hypothyroidism (56%), central hypogonadism (44%), central hypocortisolism (57%), and postprandial hypoglycemia (52%). When described (n = 15), proinsulin levels were consistently high: between 8 and 154 times the upper limit of normal (mean 74).

CONCLUSION

We described a homozygous nonsense pathogenic variant (NM_000439.4) c. 595 C>T in exon 5 of PCSK1 in a boy with congenital PC1/3 deficiency. Elevated proinsulin could be useful in the diagnosis of this condition.

Association between Insulin-Like Growth Factor-I Levels and the Disease Progression and Anemia in Visceral Leishmaniasis

We analyzed the association between insulin-like growth factor-I (IGF-I) and the pathogenesis of anemia during active visceral leishmaniasis (VL). Serum levels of IGF-I, IGF-binding protein 3 (IGFBP3), and cytokines were measured in samples from individuals with active VL and cured VL, asymptomatic Leishmania-infected, and noninfected individuals. Then, we extended our analysis to VL dogs to evaluate hematimetric parameters, bone marrow alterations, and cytokine and IGF-I expression. We identified a positive correlation between lower IGF-I and IGFBP3 levels in active VL patients and lower hemoglobin levels. In infected dogs, there was a positive correlation between lower IGF-I expression in the bone marrow and lower peripheral blood hematocrit and hemoglobin levels. There was no correlation between decreased IGF-I level/expression and any measured cytokine serum levels in either host. The data suggest that low IGF-I expression is associated with pathogenesis of anemia in active VL, primarily in severe cases, by mechanisms other than alterations in cytokine production.

Impact of the Choice of IGF-I Assay and Normative Dataset on the Diagnosis and Treatment of Growth Hormone Deficiency in Children

BACKGROUND

The analysis of insulin-like growth factor I (IGF-I) is an important tool for pediatricians in the diagnosis and treatment of growth hormone deficiency in children. However, significant differences exist in IGF-I assays and normative datasets, which can have important clinical consequences.

METHODS

IGF-I analyses were performed using the IDS-iSYS platform on 1,897 samples from pediatric patients (0.5-18 years old). Z-scores were calculated based on normative IGF-I data from Bidlingmaier et al. (SD-BM) [J Clin Endocrinol Metab. 2014 May; 99(5): 1712-21] and normative IGF-I data from the IGF-I harmonization program in the Netherlands (SD-NL). The differences in Z-scores were analyzed at relevant clinical decision points (-2 SD, +2 SD). These normative datasets were also compared to normative data reported by Elmlinger et al. [Clin Chem Lab Med. 2004; 42(6): 654-64].

RESULTS

The difference in Z-score between SD-BM and SD-NL was highest in males between 0 and 3 years old, exceeding 2 SD. Clinically relevant discordance between both Z-scores at -2 and +2 SD was found in 12.7% of all samples. The IGF-I levels at -2 and +2 SD reported in the normative dataset of Elmlinger et al. were up to 100% higher than the IGF-I levels reported by Bidlingmaier et al. or the Dutch harmonization program.

CONCLUSION

Pediatricians and laboratory specialists should be aware of relevant differences that can exist between IGF-I assays and normative data. Well-defined pediatric reference ranges for the IDS-iSYS platform are highly desirable.

Diagnosis of Idiopathic GHD in Children Based on Response to rhGH Treatment: The Importance of GH Provocative Tests and IGF-1

Purpose: Serum IGF-1 (Insulin like growth factor 1) and Growth Hormone (GH) provocative tests are reasonable tools for screening and diagnosis of idiopathic GH Deficiency (IGHD). However, the average cut-off points applied on these tests have a lower level of evidence and produce large amounts of false results. The aim of this study is to evaluate the sensitivity, specificity, and accuracy of IGF-1 and GH stimulation tests as diagnostic tools for IGHD, using clinical response to recombinant human GH (rhGH) treatment as diagnostic standard [increase of at least 0.3 in height standard deviation (H-SD) in 1 year]. Methods: We performed a prospective study with 115 children and adolescents presenting short stature (SS), without secondary SS etiologies such as organic lesions, genetic syndromes, thyroid disorders. They were separated into Group 1 [patients with familial SS or constitutional delay of growth and puberty (CDGP), not treated with rhGH], Group 2 (patients with suspicion of IGHD with clinical response to rhGH treatment), and Group 3 (patients with suspicion of IGHD without growth response to rhGH treatment). Then, they were assessed for diagnostic performance of IGF-1, Insulin Tolerance Test (ITT) and clonidine test (CT) alone and combined at different cut-off points. Results: Based on the ROC curve, the best cut-off points found for IGF-1, ITT, and CT when they were used isolated were -0.492 SDS (sensitivity: 50%; specificity: 53.8%; accuracy: 46.5%), 4.515 μg/L (sensitivity: 75.5%; specificity: 45.5%; accuracy: 52.7%), and 4.095 μg/L (sensitivity: 54.5%; specificity: 52.6%; accuracy: 56.9%), respectively. When we had combined IGF-1 with-2SD as cut-off alongside ITT or CT, we found 7 μg/L as the best cut-off point. In this situation, ITT had sensitivity, specificity and accuracy of 93.9, 81.8, and 90.1%, while CT had 93.2, 68.4, and 85.7%, respectively. Conclusion: Our data suggest that diagnosis of IGHD should be established based on a combination of clinical expertise, auxologic, radiologic, and laboratorial data, using IGF-1 at the -2SD threshold combined, with ITT or CT at the cut-off point of 7 μg/L. Additional studies, similar to ours, are imperative to establish cut-off points based on therapeutic response to rhGH in IGHD, which would be directly related to a better treatment outcome.

Reliability of clonidine testing for the diagnosis of growth hormone deficiency in children and adolescents

OBJECTIVE

The diagnosis of growth hormone deficiency (GHD) is currently based on clinical, auxological, biochemical and neuro-radiological investigation. Provocative tests of GH secretion using physiological/pharmacological stimuli are required to confirm GHD. The clonidine test (CT) is widely used to assess GH secretory status. In this retrospective study, we analyzed the reliability of CT and the effect of puberty in a large number of children with short stature who had been evaluated for suspected GHD.

DESIGN AND PATIENTS

Data were collected retrospectively from 327 children and adolescents with short stature (204 boys and 123 girls, median age 10.5 years (IQR 7.90-12.40) followed in four Italian Paediatric Endocrine Units (Cagliari, Genova, Napoli and Roma) between 2005 and 2013.

MEASUREMENTS

All children underwent CT as the first GH stimulation test after exclusion of other known cause of their short stature.

RESULTS

In 73 prepubertal children and 25 pubertal children, the GH peak after CT was <7 μg/L. GHD was confirmed in 87 (37 organic, 50 idiopathic). Six prepubertal and five pubertal patients showed false positive responses. The median BMI-SDS in these children was similar to that of children with GH peak ≥7 μg/L, and none were obese. Overall, the prevalence of false-positive responses was 3.3%. The median (IQR) peak GH after CT was similar between prepubertal and pubertal GHD (3.80 μg/L [1.7-6.00] vs 3.51 μg/L [0.76-5.74]) and non-GHD (13.70 μg/L [10.70-18.40] vs 12.40 μg/L [9.90-19.25]) children.

CONCLUSIONS

Our results show that CT is a reliable and safe GH-releasing agent in both prepubertal and pubertal children.

Decreased quality of life (QoL) in hypopituitary patients: involvement of glucocorticoid replacement and radiation therapy

PURPOSE

Hypopituitary patients are assumed to have decreased QoL due to GHD. However, in placebo controlled trials, the effects of GH replacement are no different from placebo. Hydrocortisone dose > 20 mg/day and pituitary radiation are independently associated with poorer QoL. We assessed QoL in panhypopituitary GH- deficient patients never treated with GH.

METHODS

Study group was divided into: (a) surgery followed by radiation (n = 21) and (b) surgery alone (n = 32). Mean duration of GHD was 71.4 ± 7.8 months and mean daily hydrocortisone dose was 15 ± 0.7 mg. Control group had transnasal surgery for benign sinus conditions (n = 54).

RESULTS

AGHDA scores were significantly worse in the entire study group compared to controls (8.1 ± 1.0 vs. 5.1 ± 0.9, p = 0.03). In patients with history of radiation therapy AGHDA scores were significantly worse than in controls (9.1 ± 1.5, p = 0.02) and SNOT-22 (Sino-Nasal Outcome Test) scores were also significantly worse (15.8 ± 2.0 vs. 23.2 ± 3.5, p = 0.04). However, AGHDA scores in patients without history of radiation and on "physiological" dose of hydrocortisone were similar to those in controls (5.1 ± 0.9 vs. 7.3 ± 1.3, p = 0.17).

CONCLUSIONS

Replacement with hydrocortisone doses not exceeding 20 mg/day and avoidance of radiation therapy was accompanied by normal QoL in patients not replaced with GH. Thus, we suggest that the decreased QoL in hypopituitary patients may not be due to GH deficiency per se, but rather to high hydrocortisone doses and to aftereffects of cranial radiation.

The association of insulin-like growth factor-1 standard deviation score and height in Chinese children with type 1 diabetes mellitus

Assessing the relationship between IGF-1 and height in type 1 diabetes children. Seventy-two type 1 diabetes children and 190 controls were recruited. The height standard deviation score of type 1 diabetes children was significantly higher than controls. The height standard deviation score was higher than the target height standard deviation score in both type 1 diabetes and controls. Serum IGF-1 levels and the IGF-1 standard deviation score were significantly lower in type 1 diabetes patients compared with controls. There was a significant difference in IGF-1 standard deviation score between the good glycemic control group and control group. The height standard deviation score was significantly correlated with C-peptide and IGF-1 levels. Furthermore, the IGF-1 standard deviation score was significantly correlated with glycemic control and C-peptide. The growth hormone/IGF-1 axis is impaired in type 1 diabetes, but height with good or poor glycemic control is not impaired.

Etiology of short stature in Indian children and an assessment of the growth hormone-insulin-like growth factor axis in children with idiopathic short stature

Background Our objectives were to evaluate the etiology of short stature, assess the prevalence of idiopathic short stature (ISS) and assess the growth hormone (GH)-insulin-like growth factor (IGF) axis in children with ISS. Methods A stepwise diagnostic evaluation was done in 394 children aged 4-16 years with short stature. Children with no definitive etiology were labeled as ISS. In these children, baseline IGF-1, IGF binding protein-3 (IGFBP-3) and stimulated IGF-1 after administration of GH for 4 days were measured. Results Hypothyroidism (in 18.1%) and ISS (in 15.5%) were the commonest causes of short stature. In children with ISS (n=61), the mean baseline and stimulated IGF-1 standard deviation scores (SDSs) were -1.2±1.0 and -0.3±1.4, respectively, with levels below -2 SDS in 13 (21%) and six (10%) children, respectively. In 33 (54%) of the ISS patients, response to GH was suboptimal (increment in the IGF-1 level <40%). There was no difference in the mean peak GH, IGFBP-3 and baseline and stimulated IGF-1 levels between children with familial and non-familial ISS. A significant positive correlation of height SDS with baseline IGF-1 SDS (r=0.28, p=0.026), stimulated IGF-1 SDS (r=0.32, p=0.010) and ΔIGF-1 SDS (r=0.26, p=0.036) was observed in children with ISS. Conclusions Hypothyroidism and ISS were the commonest etiologies for short stature. The baseline IGF-1 was below -2 SDS in 21% and the increment after GH stimulation was suboptimal in 54% of children, indicating that a substantial proportion of children with ISS had an impaired GH-IGF axis.