Comparison of the Clinical Utility of Two Insulin Resistance Indices: IRI-HOMA and IRI-Belfiore in Diagnosing Insulin Resistance and Metabolic Complications in Children Based on the Results Obtained for the Polish Population

Background: Recognizing insulin resistance (IR) in children remains challenging due to uncertain IRI-HOMA cut-offs and unclear recommendations for evaluating IR based on OGTT. In our study, we compare the effectiveness of IRI-HOMA and IRI-Belfiore (OGTT-based) in detecting IR and its metabolic complications in children. Methods: The analysis included 553 children who were hospitalized at the Department of Endocrinology and Metabolic Diseases of the Polish Mother's Memorial Hospital Research Institute (PMMH-RI) in Lodz, Poland, between 2002 and 2018 due to various reasons-of these, 67.5% were girls. All underwent OGTT for glucose and insulin assessment. IR diagnosis relied on IRI-HOMA and IRI-Belfiore. IR based on IRI-HOMA was evaluated using three criteria: (A) >2.5; (B) >2.67 in boys and >2.22 in girls before puberty and >5.22 and >3.82 during puberty, respectively; (C) >95th percentile according to charts for IRI-HOMA in children. Results: Prepubertal children exhibited significantly lower IRI-HOMA and IRI-Belfiore than their pubertal counterparts (p < 0.00005). IRI-HOMA and IRI-Belfiore values positively correlated with age and BMI SDS value (p < 0.000001 for all calculations). As many as 26% to 46.9% of children with normal IRI-HOMA showed elevated IRI-Belfiore, with notably higher levels of triglycerides, a lower HDL cholesterol fraction, and a lower HDL/total cholesterol ratio in this subgroup. Conclusions: A notable proportion of children exhibited elevated IRI-Belfiore levels despite having normal IRI-HOMA values. This suggests the possibility of peripheral IR preceding hepatic IR in children-omitting an OGTT may therefore lead to overlooking cases of IR. Children diagnosed with IR via OGTT displayed significantly poorer lipid profiles compared to those without IR (characterized by normal values in both IRI-HOMA and IRI-Belfiore). This underscores the ability of OGTT-derived IR indices to identify individuals at risk of developing complications associated with obesity and IR before the onset of metabolic syndrome (MS) symptoms. If IR is already detected in children based on fasting glucose and insulin levels (IRI-HOMA), further evaluation may not be warranted, as OGTT results often simply confirm the diagnosis.

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.

Involvement of Sirtuin 1 in the Growth Hormone/Insulin-like Growth Factor 1 Signal Transduction and Its Impact on Growth Processes in Children

The regulation of growth processes in children depends on the synthesis of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). Insulin-like growth factor 1, which is mainly secreted in the liver in response to GH, is the main peripheral mediator of GH action. Newly discovered factors regulating GH secretion and its effects are being studied recently. One of them is sirtuin 1 (SIRT1). This NAD+-dependent deacetylase, by modulating the JAK2/STAT pathway, is involved in the transduction of the GH signal in hepatocytes, leading to the synthesis of IGF-1. In addition, it participates in the regulation of the synthesis of GHRH in the hypothalamus and GH in the somatotropic cells. SIRT1 is suggested to be involved in growth plate chondrogenesis and longitudinal bone growth as it has a positive effect on the epiphyseal growth plate. SIRT1 is also implicated in various cellular processes, including metabolism, cell cycle regulation, apoptosis, oxidative stress response, and DNA repair. Thus, its expression varies depending on the different metabolic states. During malnutrition, SIRT1 blocks GH signal transduction in hepatocytes to reduce the IGF-1 secretion and prevent hypoglycemia (i.e., it causes transient GH resistance). In this review, we focused on the influence of SIRT1 on GH signal transduction and the implications that may arise for growth processes in children.

Osteoporosis as the First Sign of Cushing's Disease in a Thin 16-Year-Old Boy-A Case Report

Cushing's disease (CD) is an extremely rare diagnosis in children. In this report, we present the case of an almost 16-year-old, short and thin boy with CD, the first symptoms of which were spinal pain and vertebral fractures as a result of osteoporosis. In light of his growth retardation and short stature, the boy underwent diagnostics, which excluded growth hormone (GH) deficiency, hypothyroidism and celiac disease. Finally, based on cortisol profile results, dexamethasone suppression tests and bilateral sampling during catheterization of the inferior petrosal sinuses, CD was diagnosed.

The Variability of Vitamin D Concentrations in Short Children with Short Stature from Central Poland-The Effects of Insolation, Supplementation, and COVID-19 Pandemic Isolation

The aim of the study was to investigate the effects of seasonal variability of insolation, the implementation of new recommendations for vitamin D supplementation (2018), and the SARS-CoV-2 pandemic lockdown (2020) on 25(OH)D concentrations in children from central Poland. The retrospective analysis of variability of 25(OH)D concentrations during the last 8 years was performed in a group of 1440 children with short stature, aged 3.0-18.0 years. Significant differences in 25(OH)D concentrations were found between the periods from mid-2014 to mid-2018, from mid-2018 to mid-2020, and from mid-2020 to mid-2022 (medians: 22.9, 26.0, and 29.9 ng/mL, respectively). Time series models created on the grounds of data from 6 years of the pre-pandemic period and used for prediction for the pandemic period explained over 80% of the seasonal variability of 25(OH)D concentrations, with overprediction for the first year of the pandemic and underprediction for the second year. A significant increase in 25(OH)D concentrations was observed both after the introduction of new vitamin D supplementation guidelines and during the SARS-CoV-2 pandemic; however, the scale of vitamin D deficiency and insufficiency was still too high. Time series models are useful in analyzing the impact of health policy interventions and pandemic restrictions on the seasonal variability of vitamin D concentrations.

GH-secreting pituitary adenoma in the course of McCune‑Albright syndrome in a 21-year-old patient complicated by hepatocellular carcinoma

Not required for Clinical Vignette.

The incidence of insulin resistance based on indices calculated using the HOMA and Belfiore methods and its impact on the occurrence of metabolic complications in prepubertal children born small for gestational age

INTRODUCTION

Children born small for gestational age (SGA) are predisposed to obesity, insulin resistance (IR), and lipid disorders. The HOMA-IR index is commonly used to assess IR (IRIHOMA), calculated from fasting glucose and insulin. However, sometimes, during the oral glucose tolerance test (OGTT), elevated and prolonged postprandial insulin secretion is observed despite normal fasting insulin levels. IRIBelfiore is an IR index that analyses glucose and insulin levels during OGTT according to the method proposed by Belfiore.

THE AIM OF THE STUDY

was to assess the frequency of IR based on IRIHOMA and IRIBelfiore results in SGA children aged 6-8 years, after catch-up phenomenon, to determine the usefulness of IRIBelfiore in diagnosis of IR and in predicting future metabolic complications.

MATERIAL AND METHODS

In 129 SGA normal-height children, aged 6-8 years, height, weight, waist circumference, blood pressure, as well as lipids, IGF-1, cortisol, C-peptide, leptin, adiponectin, and resistin concentrations were measured. The glucose and insulin concentrations were evaluated at 0, 60, and 120 minutes of OGTT.

RESULTS

IRIHOMA was normal in all children, while elevated IRIBelfiore was found in 22.5% of them. Children with IR diagnosed by IRIBelfiore were taller, had higher blood pressure, higher leptin, and lower HDL-cholesterol concentrations.

CONCLUSIONS

It seems worth recommending IRIBelfiore derived from OGTT as a valuable diagnostic tool for identifying IR in SGA prepubertal children. Abnormal IRIBelfiore is related to higher blood pressure and lower HDL-cholesterol concentration in this group.

Safety and Efficacy of Pediatric Growth Hormone Therapy: Results From the Full KIGS Cohort

CONTEXT

The Kabi/Pfizer International Growth Database (KIGS) is a large, international database (1987-2012) of children treated with recombinant human growth hormone (rhGH) in real-world settings.

OBJECTIVE

This work aimed to evaluate the safety and efficacy of rhGH from the full KIGS cohort.

METHODS

Data were collected by investigators from children with growth disorders treated with rhGH (Genotropin [somatropin]; Pfizer). Safety was evaluated in all treated patients, and efficacy in those treated for 1 year or more. A subgroup included patients treated for 5 years or more (≥ 2 years prepubertal) who had reached near-adult height (NAH). Main outcomes included adverse events (AEs), serious AEs (SAEs), and height growth.

RESULTS

The full KIGS cohort (N = 83 803 [58% male]) was treated for idiopathic GH deficiency (IGHD; 46.9%), organic GHD (10.0%), small for gestational age (SGA; 9.5%), Turner syndrome (TS; 9.2%), idiopathic short stature (ISS; 8.2%), and others (16.2%). Median rhGH treatment duration was 2.7 years and observation 3.1 years. SAEs occurred in 3.7% of patients and death in 0.4%. The most common SAEs were recurrence of craniopharyngioma (n = 151), neoplasm (n = 99), and cancer (n = 91); and scoliosis (n = 91). Median first-year delta height-SD score (SDS) (Prader) in prepubertal patients was 0.66 (IGHD), 0.55 (ISS), 0.58 (TS), and 0.71 (SGA). Median gains in NAH-SDS were 1.79 (IGHD), 1.37 (ISS), and 1.34 (SGA) for boys, and 2.07 (IGHD), 1.62 (ISS), 1.07 (TS), and 1.57 (SGA) for girls.

CONCLUSION

Data from KIGS, the largest and longest running international database of rhGH-treated children, show that rhGH is safe and increases short-term height gain and adult height across GHD and non-GHD conditions.

Efficacy and Safety of Weekly Somatrogon vs Daily Somatropin in Children With Growth Hormone Deficiency: A Phase 3 Study

CONTEXT

Somatrogon is a long-acting recombinant human growth hormone (rhGH) in development for once-weekly treatment of children with growth hormone deficiency (GHD).

OBJECTIVE

We aimed to compare the efficacy and safety of once-weekly somatrogon with once-daily somatropin in prepubertal children with GHD.

METHODS

In this 12-month, open-label, randomized, active-controlled, parallel-group, phase 3 study, participants were randomized 1:1 to receive once-weekly somatrogon (0.66 mg/kg/week) or once-daily somatropin (0.24 mg/kg/week) for 12 months. A total of 228 prepubertal children (boys aged 3-11 years, girls aged 3-10 years) with GHD, impaired height and height velocity (HV), and no prior rhGH treatment were randomized and 224 received ≥1 dose of study treatment (somatrogon: 109; somatropin: 115). The primary endpoint was annualized HV at month 12.

RESULTS

HV at month 12 was 10.10 cm/year for somatrogon-treated subjects and 9.78 cm/year for somatropin-treated subjects, with a treatment difference (somatrogon-somatropin) of 0.33 (95% CI: -0.24, 0.89). The lower bound of the 2-sided 95% CI was higher than the prespecified noninferiority margin (-1.8 cm/year), demonstrating noninferiority of once-weekly somatrogon vs daily somatropin. HV at month 6 and change in height standard deviation score at months 6 and 12 were similar between both treatment groups. Both treatments were well tolerated, with a similar percentage of subjects experiencing mild to moderate treatment-emergent adverse events in both groups (somatrogon: 78.9%, somatropin: 79.1%).

CONCLUSION

The efficacy of once-weekly somatrogon was noninferior to once-daily somatropin, with similar safety and tolerability profiles. (ClinicalTrials.gov no. NCT02968004).

The prevalence of hypothyroxinemia in premature newborns

Congenital hypothyroidism diagnosed by TSH assessment in bloodspot screening may be overlooked in preterm newborns due to immaturity of the hypothalamus-pituitary-thyroid axis in them. The purpose of the study was to determine the prevalence and causes of hypothyroxinemia in preterm newborns, determined by TSH and FT4 serum concentration measurement, performed on the 3-5^th day of life. We assessed TSH, FT4 and FT3 serum concentration on the 3-5^th day of life in preterm children born at our centre within three consecutive years. We assessed the incidence of hypothyroxinemia, and its cause: primary hypothyroidism, secondary hypothyroidism or low FT4 syndrome - with normal TSH concentration, its dependence - among others - on gestational age (GA), birth body weight (BBW) and being SGA. A total of 525 preterm children were examined. FT4 concentration was decreased in 14.9% of preterm newborns. The most frequent cause of hypothyroxinemia was low FT4 syndrome (79.5%). More than 92% cases of hypothyroxinemia occurred in children born before the 32^nd week and/or with BBW below 1500 g. Thus, every fourth child in these groups had a reduced FT4 concentration. Neonates with hypothyroxinemia were significantly lighter than those with normal FT4. In older and heavier neonates with hypothyroxinemia, serious congenital defects were observed. Neither IVH nor SGA nor twin pregnancies predispose children to hypothyroxinemia. Among newborns with untreated hypothyroxinemia in whom TSH and FT4 assessment was repeated within 2-5 weeks, a decreased FT4 concentration was confirmed in 56.1% of cases. As hypothyroxinemia affects 25% of newborns born before the 32^nd week of gestation and those in whom BBW is less than 1500g, it seems that in this group of children the newborn screening should be extended to measure serum TSH and FT4 concentration between the 3-5^th day of life. In older and heavier neonates, additional serum TSH and FT4 assessment should be limited to children with severe congenital abnormalities but not to all SGA or twins. Despite the fact that the most common form of preterm hypothyroxinemia is low FT4 syndrome, it should be emphasized that FT4 remains lowered on subsequent testing in more them 50% of cases.

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.

Management of Prader-Labhart-Willi syndrome in children and in adults, with particular emphasis on the treatment with recombinant human growth hormone

INTRODUCTION

Prader-Willi syndrome (PWS) is a genetically determined disease that manifests itself in a number of abnormalities resulting, among others, from dysfunction of the hypothalamic-pituitary system. Only integrated, multidisciplinary care gives patients the chance to significantly improve the quality of life and achieve a life expectancy that does not differ from the general population.

AIM

The aim of the study was to summarize the available literature on the management of patients suffering from PWS.

CONCLUSIONS

More and more reports based on clinical trials conducted around the world indicate the undeniable benefits of rhGH therapy in patients with PWS in childhood and after the end of growth period. They consist in improving the body composition, improving the lipid profile, increasing bone mineral density and improving the mental state and patients' quality of life.

Karyotype Abnormalities in the X Chromosome Predict Response to the Growth Hormone Therapy in Turner Syndrome

Short stature is characteristic for Turner syndrome (TS) patients, and particular karyotype abnormalities of the X chromosome may be associated with different responsiveness to recombinant human GH (rhGH) therapy. The aim of the study was to analyze the effect of different types of TS karyotype abnormalities on the response to rhGH therapy. A total of 57 prepubertal patients with TS treated with rhGH with a 3 year follow-up were enrolled in the study and categorized according to their karyotype as X monosomy (n = 35), isochromosome (n = 11), marker chromosome (n = 5), or X-mosaicism (n = 6). Height and height velocity (HV) were evaluated annually. In the first year, all groups responded well to the therapy. In the second year, HV deteriorated significantly in X-monosomy and isochromosome in comparison to the remaining two groups (p = 0.0007). After 3 years of therapy, all patients improved the score in comparison to their target height, but better outcomes were achieved in patients with marker chromosome and X-mosaicism (p = 0.0072). X-monosomy or isochromosome determined a poorer response during the second and third year of rhGH therapy. The results of the study indicate that the effects of rhGH therapy in patients with TS may depend on the type of TS karyotype causing the syndrome.

Contribution of Ghrelin to the Pathogenesis of Growth Hormone Deficiency

In this review we described the interactions between ghrelin and the growth hormone (GH)-insulin-like growth factor 1 (IGF-1) axis in children and adults with growth hormone deficiency (GHD). A possible involvement of these interactions in the pathogenesis of unexplained cases of GHD was suggested. Current research provides more and more details to the knowledge on the circadian rhythm of ghrelin. We gathered reports on the decreasing effect of Helicobacter pylori-related chronic gastritis on the number of ghrelin immunopositive cells and the consequent decrease in ghrelin serum concentration. The gastrointestinal tract microflora modification of the ghrelin action, by the mechanism of molecular mimicry, was also stressed. Moreover, the mutual relationships between ghrelin and the TSH-FT4/FT3 axis in growth and metabolic processes are described. It is to be recalled that FT4 and FT3 exert a permissive impact on IGF-1 action and, in turn, GH, in reaction mediated by IGF-1, enhances the monodeiodination of FT4 to FT3. Finally, we discussed the latest attempts to use the GH secretagogue receptor (GHS-R) analogues for possible diagnostic and therapeutic purposes.

Effects of Recombinant Human Growth Hormone Treatment, Depending on the Therapy Start in Different Nutritional Phases in Paediatric Patients with Prader-Willi Syndrome: A Polish Multicentre Study

Recombinant human growth hormone (rhGH) treatment is an established management in patients with Prader-Willi syndrome (PWS), with growth promotion and improvement in body composition and possibly the metabolic state. We compared anthropometric characteristics, insulin-like growth factor 1 (IGF1) levels, metabolic parameters and the bone age/chronological age index (BA/CA) in 147 children with PWS, divided according to age of rhGH start into four groups, corresponding to nutritional phases in PWS. We analysed four time points: baseline, rhGH1 (1.21 ± 0.81 years), rhGH2 (3.77 ± 2.17 years) and rhGH3 (6.50 ± 2.92 years). There were no major differences regarding height SDS between the groups, with a higher growth velocity (GV) (p = 0.00) and lower body mass index (BMI) SDS (p < 0.05) between the first and older groups during almost the whole follow-up. IGF1 SDS values were lower in group 1 vs. other groups at rhGH1 and vs. groups 2 and 3 at rhGH2 (p < 0.05). Glucose metabolism parameters were favourable in groups 1 and 2, and the lipid profile was comparable in all groups. BA/CA was similar between the older groups. rhGH therapy was most effective in the youngest patients, before the nutritional phase of increased appetite. We did not observe worsening of metabolic parameters or BA/CA advancement in older patients during a comparable time of rhGH therapy.

Switch Data From the Open-Label Extension of the Pivotal Phase 3 Study of Once Weekly Somatrogon Compared to Daily Somatropin in Pediatric Patients With Growth Hormone Deficiency (pGHD)

Objectives: Somatrogon (hGH-CTP) is a long acting recombinant human growth hormone, consisting of the amino acid sequence of hGH and three copies of the carboxy-terminal peptide (CTP) of human chorionic gonadotropin (hCG) being developed as a once weekly treatment for children with pGHD. This report summarizes data from the first year of the optional open-label extension (OLE) of the pivotal phase 3 global trial (ClinicalTrials. gov: NCT02968004), comparing the efficacy and safety of children switched from Genotropin (rhGH; somatropin) to somatrogon (Geno/Soma) and children maintained on somatrogon (Soma/Soma).

Methods: During the main study, 224 children were randomized to receive either once weekly somatrogon (0.66 mg/kg, n=109) or once daily Genotropin (0.24 mg/kg/wk, n=115) for 12 months. Of these, 222 completed the 12-month main study, and 212 chose to enter the OLE study. By Sept 30, 2020, 161 children (including 76 Geno/Soma) had complete auxological data at month 12 of the OLE.

Results: At the end of the main study, mean height velocity and gain in height SDS for the somatrogon cohort were 10.10 cm/year and 0.92; for the Genotropin cohort these were 9.78 cm/year and 0.87. Baseline values for the OLE (Soma/Soma group and Geno/Soma group, respectively): height SDS was -1.95 and -1.84, BMI was 17.03 and 15.48 kg/m2 while bone age was 6.54 and 6.40 years. At month 12 (of the OLE), the mean height velocity and the change in height SDS was 8.04 cm/year and 0.41 (Soma/Soma group) and 8.21 cm/year and 0.47 (Geno/Soma group); BMI was 18.07 and 17.49 kg/m2 and bone age was 8.48 and 8.41 years. IGF-1 SDS values were 1.15, and 1.28, while the IGFBP-3 SDS were 0.29 and 0.42, respectively. Dose reductions were required in 16.3% and 20.4% of patients due to IGF-1 SDS &gt;2. Pubertal status changed from Tanner 1 (at OLE baseline) for 13.6% of Soma/Soma patients and 14.6% of Geno/Soma patients. Mean glucose, HbA1c, thyroid function (free T4 and TSH) and cholesterol (total, LDL and HDL) values remained similar to baseline in both groups across the 12 months OLE. The majority of adverse events in both cohorts were mild to moderate (Soma/Soma 94.2%, Geno/Soma 93.5%) and there were no clinically concerning safety observations. During the first 12 months of the OLE six patients discontinued in the Geno/Soma group due to AEs vs zero in the Soma/Soma group.

Conclusions: Height velocities and change in height SDS in the OLE were similar between the Geno/Soma and Soma/Soma cohorts. The main phase of the global pivotal phase 3 trial demonstrated that somatrogon (hGH-CTP) given once weekly is non-inferior to Genotropin (hGH) while the OLE demonstrated that catch-up growth continued into the second year of treatment, with ‘switch’ from Genotropin to somatrogon non-inferior to somatrogon given for two years. Metabolic (glycemic, lipid and thyroid) parameters were similar between groups and not meaningfully different from the main study.

Transient Hyperthyrotropinemia in Outpatient Children with Acute Infections of the Respiratory System

Background: Diagnostics of thyroid disorders (TD) are frequently based on the measurements of thyroid stimulating hormone (TSH) concentration only. If TSH is outside the reference range, the diagnostic procedure used in patients with TD isintroduced. Observations indicate that in a considerable number of these patients, TD is not confirmed. The aim of the study was to assess the incidence of transient hyperthyrotropinemia in healthy children during acute infections of the respiratory system. Patients and Methods: The study included consecutive children (49 boys and 45 girls), aged 2.2–17.3 years, who visited one General Practitioner (GP) due to respiratory tract infections. The tests: complete blood count (CBC), C-reactive protein (CRP), TSH and FT4 were run on the next day after the visit at the physician’s (initial visit) and ≥2 weeks after recovery. Results: Among these children, elevated TSH values were found in about 10% of patients, and they went back to normal values after recovery. A prospective analysis showed a reduction of TSH values in approx. 65% of all groups and TSH at the follow-up visit was significantly lower. Conclusions: Transient hyperthyrotropinemia was observed in about 10% of children with acute respiratory tract infection. This preliminary finding remains unexplained.

Frequency of oligosymptomatic gastrointestinal tract diseases and its relation to insulin-like growth factor I in idiopathic (non-GH-deficient) short stature children

INTRODUCTION

There is a discussion about growth hormone therapy in idiopathic short stature (ISS) children. To diagnose ISS, it is necessary to exclude other diseases; gastrointestinal tract diseases (GIDs) are among them. However, GID symptoms may be scarce. The aim of the study was to evaluate the frequency of unexpected oligosymptomatic GIDs in ISS and assess their influence on auxological parameters and insulin-like growth factor I (IGF-I) concentration.

MATERIAL AND METHODS

The analysis included 101 children with ISS and 95 controls. All patients were tested for celiac disease (CD), inflammatory bowel disease (IBD), lactose malabsorption (LM), cystic fibrosis (CF), Helicobacter pylori (HP) and Ascaris sp. (Asc) infections, as well as Candida albicans (Calb) colonization, by applying simple blood and stool tests and gastrofiberoscopy.

RESULTS

In 75.2% of short children, one or more than one GIDs listed above were diagnosed, with the highest frequency of: Calb (46.5%), LM (33.7%), HP (24.7%) and/or Asc (21.8%). The incidence of GIDs was significantly higher than in the control group. The GID frequency increases with the age of children. In most ISS children, the IGF-I SDS was below -1.0 and it was the lowest in children with HP (p < 0.05).

CONCLUSIONS

High frequency of unexpected oligosymptomatic GIDs in children diagnosed with ISS indicates the need to search for gastrointestinal (GI) causes in each case of short stature in children. The pathomechanisms responsible for short stature in these cases may vary, although it seems that reduced production of IGF-I plays an important role.

Effectiveness, economical and safety aspects of growth hormone (GH) therapy in growth promoting doses in patients with isolated GH deficiency after the attainment of near-final height. Is there a need to modify the criteria of therapy withdrawal?

INTRODUCTION

Apart from growth promotion, growth hormone (GH) has important metabolic effects. Patients with severe GH deficiency (GHD) should be treated with GH throughout life. Current criteria for growth promoting therapy withdrawal in Poland differ from the latest recommendations. Aim of the study To assess cost-effectiveness and safety of continuation of GH therapy in growth promoting doses in patients with isolated GHD after the attainment of near-final height (near-FH) and the incidence of persistent GHD after the therapy withdrawal.

MATERIAL AND METHODS

160 children with isolated GHD (height < 3 centile, GH peak < 10.0 µg/l), who continued GH therapy for growth promotion after the attainment of near-FH (height velocity   2.0) at near-FH and incidence of severe GHD in retesting (performed in 62 patients).

RESULTS

Height gain after near-FH was 1.1 ±0.8 cm in boys and 1.0 ±0.8 in girls. Increase of height by 1.0 cm required on average 487 mg of GH (264 injections). IGF-1 concentrations at near-FH were increased in 39 patients, with no clinical side effects. None of the patients retested had GH peak   10.0 µg/l.

CONCLUSIONS

There is no rationale to continue GH therapy in growth promoting doses in the patients with isolated GHD after fulfilling the criteria of near-FH.

Application of Shear Wave Sonoelastography in the Differential Diagnosis of Extra- and Intra-Thyroidal Ectopic Thymic Tissue

The ultrasound (US) pattern of intrathyroidal ectopic thymus (IET) can resemble papillary thyroid carcinoma (PTC) while the extrathyroidal ectopic thymus (EET) can mimic pathological lymph nodes. Recently, the usefulness of strain elastography (SE) was demonstrated in the differential diagnosis, however this method has several limitations. The aim of the current study was to assess the usefulness of shear wave elastography (SWE) in this field. The US, SE, and SWE were performed in 31 children with 53 ectopic thymuses (ETs) and quantitative values of SWE parameters were calculated, so as to generate potential normative values of ET elasticity and of the shear wave ratio (SWR). The mean SWR_IET was 0.89 ± 0.21 and the mean shear wave stiffness (SWS) was 7.47 ± 1.93 kPa. The mean SWR_EET was 0.84 ± 0.15 and the mean SWS_EET was 11.28 ± 2.58 kPa. The results have proven that the stiffness of ETs is lower or equal to the thyroid’s. SWE was demonstrated to be a useful diagnostic method for ET evaluation. Therefore, the application of SWE in ET diagnosis allows more accurate evaluation of ET-like lesions and, in many cases, allows one to avoid invasive procedures, simultaneously providing a precise monitoring method based on combined US and SWE evaluation.

Strong Positive Correlation between TSH and Ghrelin in Euthyroid Non-Growth Hormone-Deficient Children with Short Stature

The growth processes in children depend on the proper functioning of some hormones and growth factors. Recently, a positive correlation between ghrelin and TSH (thyroid stimulating hormone) in patients with hyper- and hypothyroidism was proved. Moreover, in hypothyroid rats with high ghrelin concentration, growth hormone (GH) and insulin-like growth factor I (IGF-I) secretion was suppressed. We analyzed these relationships in euthyroid prepubertal children with idiopathic short stature (ISS). The analysis comprised concentration of ghrelin, GH in stimulating tests and during the night, as well as IGF-I, TSH, free thyroxine (FT4) and free triiodothyronine (FT3) in 85 children with ISS (36 girls, 49 boys) aged 9.65 ± 3.02 years (mean ± SD). A strong positive correlation between ghrelin and TSH was confirmed (r = +0.44, p < 0.05). A higher ghrelin but lower nocturnal GH and lower IGF-I were observed in children with higher normal TSH concentration than those in children with lower normal TSH. Interestingly, alterations of TSH level were without any impact on FT4 and FT3 concentrations. Summing up, in ISS prepubertal euthyroid children, ghrelin and TSH secretion are closely related. On the other hand, the higher the TSH, the lower the nocturnal GH and IGF-I levels. The contribution of the above findings in deterioration of growth processes requires further studies.

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.

Sonographic and Elastographic Features of Extra- and Intrathyroidal Ectopic Thymus Mimicking Malignancy: Differential Diagnosis in Children

Thyroid nodules with ultrasound (US) cancer risk features and extra-thyroid lesions suggesting malignant lymph nodes, require prompt diagnosis, especially in children. The US pattern of intrathyroidal ectopic thymus (IET) can strongly suggest papillary thyroid carcinoma (PTC). The extra-thyroid ectopic thymic tissue (EET) can mimic pathological lymph nodes in US. The aim of the study has been to demonstrate US features and diagnostic methods, allowing finally to confirm the presence of IET and EET in children. The US and elastographic features of 16 ectopic thymic tissue (ET) lesions were analyzed so as to describe the typical characteristics of ET and to define the best method to differentiate ET and malignant lesions. Among 16 analyzed lesions, 11 lesions were IET, and 5 were EET adjacent to the thyroid connective tissue capsule. Most of IET were located in the middle part of the right lobe and were fusiform or oval in shape. All the lesions were solid, hypoechoic, and heterogeneous with bright internal echoes. Among IET, 73% of lesions had well- or very well-defined margins. In strain elastography of IET lesions, the strain ratio was similar in all lesions, and its value ranged from 0.95 to 1.09. Despite the low prevalence of IET and cervical EET, clinicians and radiologists should be aware of US characteristics of such lesions. The confirmation of their benign character is absolutely required. Elastography is a useful tool to initially differentiate PTC and IET. However, due to high risk of malignancy in thyroid lesions in children, similarity of US features of PTC and IET, and due to the possibility of malignancy in ET, only cytological evaluation provides definitive diagnosis.

National Program of Severe Growth Hormone Deficiency Treatment in Adults and Adolescents after Completion of Growth Promoting Therapy

Growth hormone (GH) has been used in the treatment of short stature in children with GH deficiency (GHD) for 60 years, and for about 30 years also in the treatment of adults with GHD, in whom such treatment is carried out due to metabolic indications. In Poland, GH treatment is reimbursed only in children with GHD, while so far it has not been refunded in adults with GHD. There are two groups of adults (or adolescents after growth completion) with GHD, who require GH therapy: patients with GHD that occurred in childhood (childhood-onset GHD - CO-GHD) and patients with GHD acquired in adulthood (adulthood-onset GHD - AO-GHD). This review presents a brief outline of the history of GH treatment in humans, the latest data on the causes and symptoms of GHD in adults, and the complications of untreated GHD. Current recommendations regarding diagnosis, treatment and monitoring of GH therapy in adults are also discussed. Moreover, the review paper presents the objectives, assumptions, and plans of implementation of the "National Treatment Program for Severe Growth Hormone Deficiency in Adults and Adolescents after Completion of the Growth Promoting Therapy", as well as the expected health and economic effects of introduction of GH treatment in adults with GHD in Poland.

Pre-treatment growth and IGF-I deficiency as main predictors of response to growth hormone therapy in neural models

Mathematical models have been applied in prediction of growth hormone treatment effectiveness in children since the end of 1990s. Usually they were multiple linear regression models; however, there are also examples derived by empirical non-linear methods. Proposed solution consists in application of machine learning technique - artificial neural networks - to analyse this problem. This new methodology, contrary to previous ones, allows detection of both linear and non-linear dependencies without assuming their character a priori The aims of this work included: development of models predicting separately growth during 1st year of treatment and final height as well as identification of important predictors and in-depth analysis of their influence on treatment's effectiveness. The models were derived on the basis of clinical data of 272 patients treated for at least 1 year, 133 of whom have already attained final height. Starting from models containing 17 and 20 potential predictors, respectively for 1st year and final height model, we were able to reduce their number to 9 and 10. Basing on the final models, IGF-I concentration and earlier growth were indicated as belonging to most important predictors of response to GH therapy, while results of GH secretion tests were automatically excluded as insignificant. Moreover, majority of the dependencies were observed to be non-linear, thus using neural networks seems to be reasonable approach despite it being more complex than previously applied methods.

Relationship between IGF-I Concentration and Metabolic Profile in Children with Growth Hormone Deficiency: The Influence of Children's Nutritional State as well as the Ghrelin, Leptin, Adiponectin, and Resistin Serum Concentrations

BACKGROUND

Some, however not all, children with growth hormone deficiency (GHD) reveal a tendency towards metabolic disorders. Insulin-like growth factor I (IGF-I) is the main mediator of GH anabolic effects.

OBJECTIVE

The aim of the study was to compare ghrelin, adiponectin, leptin, resistin, lipid, glucose, and insulin concentrations in GHD children, depending on the IGF-I bioavailability.

METHODS

The analysis comprised 26 children with GHD, aged 5.7-15.3 yrs. Fasting serum concentrations of IGF-I, IGFBP-3, ghrelin, leptin, adiponectin, resistin, lipids, glucose, and insulin were measured. The GHD children were divided into two subgroups: (1) with lower IGF-I/IGFBP-3 molar ratio and (2) with higher IGF-I/IGFBP-3 molar ratio. The control group consisted of 39 healthy children, aged 5.1-16.6 yrs, of normal height and body mass.

RESULTS

GHD children with lower IGF-I/IGFBP-3 molar ratio were found to have a significantly lower body mass and insulin and triglyceride concentrations, as well as significantly higher ghrelin and adiponectin concentrations than GHD children with higher IGF-I/IGFBP-3.

CONCLUSIONS

A better metabolic profile characterised GHD children with low IGF-I bioavailability. This phenomenon may be the result of high adiponectin and ghrelin concentrations in those children and their influence on adipose tissue, glucose uptake, and orexigenic axis.

The influence of INS VNTR class III allele on auxological parameters, glucose, insulin, lipids, and adipocytokines secretion in prepubertal children born small for gestational age

INTRODUCTION

The insulin gene variable number of tandem repeats (INS VNTR) class III allele has been implicated in lower birth weight, obesity, and insulin resistance. We assessed its influence on birth weight in the Polish population and on the current body mass and metabolic profile in prepubertal children born small for gestational age (SGA).

MATERIAL AND METHODS

DNA for genotyping of INS VNTR was available for 123 subjects born SGA and 132 born appropriate for gestational age (AGA). We identified two alleles: class I and class III. Next, in 112 prepubertal (aged: 6.8 ± 1.38 years) SGA children, the auxological measurements, fasting serum C-peptide, triglycerides, cholesterol, ghrelin, leptin, adiponectin, resistin, cortisol, and insulin-like growth factor type I (IGF-I) concentrations, as well as glucose and insulin during oral glucose tolerance test (OGTT), were assessed and insulin resistance indices were calculated. The results were analysed depending on INS VNTR variants.

RESULTS

The occurrence of individual INS VNTR variants were similar in the SGA and AGA groups. In prepubertal SGA children, we did not observe any statistical differences as regards birth weight, body mass, lipids, or adipocytokine concentrations among I/I, I/III, and III/III class groups. The concentration of insulin in 120' of OGTT was significantly higher in class III homozygous than in class I homozygous individuals.

CONCLUSIONS

Variant INS VNTR class III was shown not to be associated in any essential way with birth weight in the Polish population. Among prepubertal SGA children, the presence of INS VNTR class III is related to higher insulin secretion during OGTT. (Endokrynol Pol 2016; 67 (6): 585-591).

Incidence and predictors of persistent growth hormone deficiency (GHD) in patients with isolated, childhood-onset GHD

INTRODUCTION

In a considerable proportion of patients with childhood-onset growth hormone (GH) deficiency (GHD), a normalisation of GH secretion at the attainment of final height (FH) is observed. The aim of the present study was to assess the incidence of, and to find out the predictors of, persistent and transient GHD, available in the pre-treatment period, in patients with childhood-onset isolated, non-acquired GHD.

MATERIAL AND METHODS

The analysis comprised 150 short children (117 boys), with childhood-onset isolated, non-acquired GHD who completed GH therapy and attained FH. Before treatment and at FH (in retesting), auxological parameters were measured, GH peak in stimulation tests and IGF-I concentration were assessed, and pituitary height (PHt) was measured before treatment.

RESULTS

The incidence of persistent GHD was 12.0%. The patients with persistent GHD had before treatment significantly lower GH and IGF-I secretion, as well as significantly better increase of height SDS (DHSDS) during GH therapy than those with transient GHD. A negative correlation was observed between DHSDS and IGF-I concentration, but not between DHSDS and GH peak. There was no significant difference in the incidence of pituitary hypoplasia between the patients with persistent and transient GHD.

CONCLUSIONS

The incidence of persistent GHD in patients with childhood-onset, isolated, non-acquired GHD is relatively low. Despite the fact that the predictors of persistent and transient GHD may be identified in childhood, a diagnosis of GHD should be verified in retesting after the attainment of FH in each case.

Ghrelin, insulin-like growth factor I and adipocytokines concentrations in born small for gestational age prepubertal children after the catch-up growth

BACKGROUND

In children born small for gestational age (SGA) with catch-up growth, a higher risk of insulin resistance (IR) and cardiovascular diseases is noted. Ghrelin stimulates a growth hormone (GH) secretion and regulates lipid and carbohydrate metabolism. We assessed gherlin's influence on achieving normal height and the occurrence of metabolic complications in SGA children.

METHODS

Ghrelin, insulin-like growth factor type I (IGF-I), leptin, adiponectin, resistin, glucose, insulin and lipid concentrations were analysed in 134 prepubertal children in four groups: normal-height SGA, short SGA, normal-height born appropriate for gestational age (AGA) and short AGA.

RESULTS

Ghrelin and IGF-I concentrations were significantly higher while adiponectin - lower in normal-height SGA comparing to others.

CONCLUSIONS

The increased production of ghrelin and IGF-I seems to be an adaptive mechanism to achieve normal growth in SGA children. The significance of high ghrelin and low adiponectin concentrations, observed in normal-height prepubertal SGA children, requires elucidation, with reference to the development of metabolic complications.

In children with autoimmune thyroiditis CTLA4 and FCRL3 genes--but not PTPN22--are overexpressed when compared to adults

BACKGROUND

Numerous genetic studies revealed several susceptibility genes of autoimmune thyroid diseases (AITD), including CTLA4, PTPN22 and FCRL3. These immune-modulating genes are involved in genetic background of AITD among children and adult patients. However, possible age-related differences in overexpression of these genes remain unclear.

PURPOSE

The goal of this single centre cohort study was evaluation of expression levels of three (3) genes CTLA4, PTPN22 and FCRL3 in adult patients and children with autoimmune thyroiditis.

METHODS

A total of 47 patients--24 adults (mean age--47.7 years) and 23 children (mean age--12.4 years) with autoimmune thyroiditis were assessed for the level of expression of CTLA4, PTPN22 and FCRL3 genes, utilizing ABI PRISM' 7500 Sequence Detection System (Applied Biosystem, Foster City, CA, USA).

RESULTS

The overexpression of PTPN22 (mean RQ = 2.988) and FCRL3 (mean RQ = 2.544) genes were confirmed in adult patients with autoimmune thyroiditis, at the same time the expression level of CTLA4 gene was significantly decreased (mean RQ = 0.899) (p < 0.05). Similar discrepancies were not observed in children with autoimmune thyroiditis in whom overexpression of all three genes--CTLA4, PTPN22 and FCRL3--was observed. Differences in CTLA4 and FCRL3 genes expression levels in patients with autoimmune thyroiditis were found depending on the age, with increased expression levels of CTLA4 (mean RQ = 3.45 1) and FCRL3 (mean RQ = 7.410) in children when compared to adults (p < 0.05) (Mann-Whitney's U-test). There were moderate negative linear correlations between two genes in question (CTLA4 and FCRL3) expression level and patients' age [correlation coefficient (r) = -0.529 (p < 0.0002) and -0.423 (p < 0.0032), respectively; Spearman's rank correlation test].

CONCLUSION

Our results are consistent with the hypothesis that there are few age-dependent genetic differences as regards autoimmune thyroiditis in adults and children. Accordingly, CTLA4 and FCRL3 genes overexpression may play an important role in children suffering from autoimmune thyroiditis.

Secondary IGF-I deficiency as a prognostic factor of growth hormone (GH) therapy effectiveness in children with isolated, non-acquired GH deficiency

OBJECTIVE

Growth hormone (GH) deficiency (GHD) has recently been classified as secondary IGF-I deficiency but the significance of IGF-I measurement in diagnosing GHD is still discussed. The aim of the study was to assess the relationships between IGF-I secretion and GH therapy effectiveness in children with GHD.

PATIENTS AND METHODS

The analysis comprised 300 children with isolated, non-acquired GHD (GH peak below 10 μg/l) who completed GH therapy and attained final height (FH). In all patients IGF-I concentration was measured before the treatment and IGF-I deficiency was diagnosed if IGF-I SDS for age and sex was below -1.0. The following auxological indices were assessed: patients' height SDS before treatment (H₀SDS), FH SDS and improvement of FHSDS vs. H₀SDS (ΔHSDS).

RESULTS

In the patients with IGF-I deficiency when compared with those with normal IGF-I secretion before treatment, significantly better FH SDS (-1.42±0.90 vs. -1.74±0.86, p=0.004) and ΔHSDS (1.64±1.01 vs. 1.32±1.05, p=0.010) were observed, despite similar H₀SDS (- 3.07±0.78 vs. - 3.11±0.77, p=0.63) and GH peak (7.0±3.1 μg/l vs. 6.8±2.1 μg/l, p=0.55). The patients who achieved FH over 10(th) centile had significantly lower IGF-I SDS before treatment than those with FH below 10(th) centile (- 1.59±1.54 vs. - 1.20±1.64, p=0.04), despite similar GH peak (7.0±2.3 μg/l vs. 6.7±3.1 μg/l, p=0.45). The patients with ΔHSDS over the median value had significantly lower IGF-I SDS than those with ΔHSDS below the median value (- 1.59±1.71 vs. - 1.09±1.47, p<0.0001), despite similar GH peak (6.8±2.5 μg/l vs. 7.0±2.7 μg/l, p=0.86).

CONCLUSION

In children with isolated, non-acquired GHD, secondary IGF-I deficiency is an important predictor of better GH therapy effectiveness.

Neural network models - a novel tool for predicting the efficacy of growth hormone (GH) therapy in children with short stature

INTRODUCTION

The leading method for prediction of growth hormone (GH) therapy effectiveness are multiple linear regression (MLR) models. Best of our knowledge, we are the first to apply artificial neural networks (ANN) to solve this problem. For ANN there is no necessity to assume the functions linking independent and dependent variables. The aim of study is to compare ANN and MLR models of GH therapy effectiveness.

MATERIAL AND METHODS

Analysis comprised the data of 245 GH-deficient children (170 boys) treated with GH up to final height (FH). Independent variables included: patients' height, pre-treatment height velocity, chronological age, bone age, gender, pubertal status, parental heights, GH peak in 2 stimulation tests, IGF-I concentration. The output variable was FH.

RESULTS

For testing dataset, MLR model predicted FH SDS with average error (RMSE) 0.64 SD, explaining 34.3% of its variability; ANN model derived on the same pre-processed data predicted FH SDS with RMSE 0.60 SD, explaining 42.0% of its variability; ANN model derived on raw data predicted FH with RMSE 3.9 cm (0.63 SD), explaining 78.7% of its variability.

CONCLUSION

ANN seem to be valuable tool in prediction of GH treatment effectiveness, especially since they can be applied to raw clinical data.

Prevalence of autoantibodies against some selected growth and appetite-regulating neuropeptides in serum of short children exposed to Candida albicans colonization and/or Helicobacter pylori infection: the molecular mimicry phenomenon

OBJECTIVES

Many of peptides synthesized in gastrointestinal tract (GI) and adipose tissues, regulate growth and food intake. The GI microflora is an antigenic source. Based on the molecular mimicry hypothesis, intestinal microbe-derived antigens may trigger the production of autoantibodies cross-reacting with some neuropeptides.

DESIGN

The aim of the study was to assess whether in idiopathic short stature (ISS) children with Candida albicans (C.albicans) colonisation and/or Helicobacter pylori (H.pylori) infection the autoantibodies (in positive levels) against selected neuropeptides [anti-NP Abs(+)]: ghrelin, leptin, orexin A, αMSH are more prevalent than in Controls.

SETTING

The study group comprised 64 children with ISS and 36 children with normal height (Controls). In each child, IgG antibodies against H.pylori, ghrelin, leptin, orexin A and αMSH were assessed in serum, while presence of C.albicans - in stool samples.

RESULTS

The higher prevalence of anti-NP Abs(+) in ISS children with C.albicans and/or H.pylori than in normal height children with the colonization in question (34.4% vs 21.1%, p<0.01) was found. The prevalence of anti-NP Abs(+) in groups of children without C.albicans and H.pylori were low, anti-NP Abs(+) were detected in 9.4% of ISS children only, while in Controls they were not found.

CONCLUSIONS

In short children with C.albicans and/or H.pylori the incidence of autoantibodies against selected neuropeptides is high. It probably is connected with molecular mimicry between antigens of these microbiota and the mentioned peptides. It is tempting to speculate that presence of cross-reacting autoantibodies against regulatory neuropeptides may results in worse growth velocity. However, further studies are necessary to elucidate this issue.

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

INTRODUCTION AND OBJECTIVE

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.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

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.

Frequency of the E23K polymorphism of the KCNJ11 gene in children born small for gestational age and its influence on auxological and metabolic parameters in the prepubertal period

BACKGROUND

The E23K variant of the KCNJ11 gene is possibly responsible for changes in insulin secretion during the fetal life. We tried to assess the influence of the E23K variant on birth weight and metabolic profile in prepubertal children born small for gestational age (SGA).

SUBJECTS

One hundred and twenty-three SGA and 132 born appropriate for gestational age (AGA) children were genotyped for the E23K variant. Lipids, glucose, and insulin concentrations during oral glucose tolerance test were assessed in 112 SGA prepubertal children.

RESULTS

There were no significant differences between the frequency of the E23K variant in SGA and AGA children. In SGA children with E23K, the mean birth weight was significantly higher than in the E23E group. Body mass index, glucose, insulin, and lipids were not different between the E23K, E23E, and K23K groups.

CONCLUSIONS

The higher birth weight in SGA children with the E23K variant may be related to higher insulin concentrations in the fetal period. The E23K variant did not affect metabolic disorders in prepubertal SGA children.

Significant increase of IGF-I concentration and of IGF-I/IGFBP-3 molar ratio in generation test predicts the good response to growth hormone (GH) therapy in children with short stature and normal results of GH stimulating tests

BACKGROUND

Insulin-like growth factor-I (IGF-I) generation test has been introduced for the assessment of growth hormone (GH) sensitivity, however, its significance in predicting growth response to GH therapy has also been brought up. The molar ratio of IGF-I to its binding protein-3 (IGFBP-3) determines IGF-I bioavailability.

AIMS

Evaluation of usefulness of IGF-I and IGFBP-3 generation test in predicting the effectiveness of rhGH therapy in children with short stature.

PATIENTS AND METHODS

The analysis comprised 60 children with short stature, normal results of GH stimulating tests but decreased IGF-I secretion. In all the patients, GH insensitivity was excluded on the basis of IGF-I and IGFBP-3 generation test. Next, GH therapy was administered and height velocity (HV), together with IGF-I and IGFBP-3 secretion, was assessed every year, during 3 years. The comparative group consisted of 30 children with partial GH deficiency (pGHD).

RESULTS

Both IGF-I secretion and IGF-I/IGFBP-3 molar ratio increased significantly during generation test (p<0.05) and - further - during GH therapy (however insignificantly), together with at least doubling of pretreatment HV. There was no significant difference between the studied group of patients and children with pGHD.

CONCLUSIONS

Significant increase of IGF-I in generation test speaks for GH therapy effectiveness in short children, despite normal results of GH stimulating tests.

High concentration of ghrelin in children with growth hormone deficiency and neurosecretory dysfunction

BACKGROUND

The role of endogenous ghrelin in the growth process of children is unclear. The aim of the present study was to assess ghrelin concentrations in children with growth hormone deficiency (GHD), neurosecretory dysfunction (NSD) and idiopathic short stature (ISS) in comparison to healthy controls.

MATERIAL

One hundred and forty seven children (61 girls and 86 boys), aged 3.7-16.8 years (mean±SD: 10.7±3.44 years) with short stature (below -2.0 SD) were qualified into the study. In each child, fasting ghrelin and insulin-like growth factor type I (IGF-I) concentrations were measured and growth hormone (GH) secretion was assessed after falling asleep and during two GH-stimulating tests. According to maximal GH concentrations, children were qualified into GHD, NSD and ISS group. Additionally, depending on biological development, the children were divided on younger and older subgroups. The control group consisted of 19 healthy children with normal height and body mass.

RESULTS

Ghrelin concentrations in GHD (1847.5±1444.3 pg/mL) and NSD (1809.3±983.5 pg/mL) were significantly higher than in ISS (1218.1±646.8 pg/mL) and in Controls (924.9±318.4 pg/mL). A comparison of ghrelin concentrations in older and younger children within the same diagnostic group, showed statistically higher ghrelin levels in younger than in older children (except of NSD group, in which the difference reached the border of statistical significance).

CONCLUSIONS

Ghrelin concentration is elevated in GHD and NSD children. Independently of GH and IGF-I secretion disorders type, ghrelin concentrations decrease with the children' age. The higher concentration of ghrelin in ISS than in Controls suggests the presence of GH-independent factors increasing ghrelin secretion by X/A cells in the gastric oxyntic mucosa.

Ghrelin concentration is correlated with IGF-I/IGFBP-3 molar ratio but not with GH secretion in children with short stature

OBJECTIVES

In children with growth hormone deficiency (GHD) and neurosecretory dysfunction (NSD) ghrelin concentrations are significantly higher than in children with idiopathic short stature (ISS), however the correlation between serum ghrelin and growth hormone (GH) is not observed. The aim of the study was to compare ghrelin concentrations with IGF-I/IGFBP3 molar ratio in children with short stature due to different etiology.

MATERIAL

Analysis comprised 136 children (58 girls and 78 boys), aged 3.86-16.82 years with short stature (below -2.0 SD); in 21 of them GHD was diagnosed, in 23 - NSD and 92 - ISS. In each child, fasting ghrelin, insulin-like growth factor type I (IGF-I) and its binding protein type 3 (IGFBP-3) concentrations were measured. The results were analysed separately in younger and in older children. Depending on IGF-I/IGFBP-3 molar ratio, children were divided into two (2) groups: with lower IGF-I/IGFBP-3 and with higher IGF-I/IGFBP-3 ratio value.

RESULTS

Both in younger and in the older age groups, ghrelin concentration was significantly higher in children with lower IGF-I/IGFBP-3 ratio than in children with higher IGF-I/IGFBP-3 value (1937.3±1232.4 vs 1365.3±632.1 pg/ml in younger children and 1205.4±548.8 vs 867.4±282.9 pg/ml in older children). The negative correlation between ghrelin and IGF-I/IGFBP-3 ratio was observed in both age groups. Not only children with GHD and NSD, but also as much as 39% out of all children with ISS were qualified into the subgroups with lower IGF-I/IGFBP-3 ratio.

CONCLUSIONS

Ghrelin secretion is elevated in children with lower IGF-I/IGFBP-3 ratio. It seems that lower bioactivity of IGF-I is stimulating factor for ghrelin synthesis.

Growth hormone (GH) peak after falling asleep reflects spontaneous nocturnal GH secretion, however is not corresponding to the results of GH stimulating tests in children with short stature

OBJECTIVE

Growth hormone (GH) secretion is characterized by a pulsatile, circadian rhythm, with the highest concentrations at night hours. Evaluation of nocturnal GH secretion may be truncated to 6 hours. Growth hormone stimulating tests are the standard method of assessment of GH secretion. In Poland, the assessment of GH peak during 2 hours after falling asleep was introduced as a screening procedure in children, suspected for GH deficiency. The aim of current study was to compare the results of a screening test with GH secretion during 6-hour nocturnal profile and with the results of GH stimulating tests, as well as with IGF-I secretion in children with short stature.

METHODS

In 72 short children, GH concentrations were measured every 30 minutes during first 6 hours after falling asleep and in two GH stimulating tests (the cut-off level of GH peak for all the tests was 10.0 ng/ml). Also, IGF-I concentrations were measured and expressed as IGF-I SDS for age and sex.

RESULTS

The screening test results correlated significantly with both GH peak in 6-hour profile and mean GH concentration, and the area under the curve (AUC) in 6 hour profile (r= 0.94, r=0.90 and r=0.89, respectively, p<0.05) but not with GH peak in stimulating tests (r=0.07, NS). There was no correlation between IGF-I secretion and any of the analyzed parameters of spontaneous and stimulated GH secretion.

CONCLUSIONS

The results of screening test seem to reflect overnight GH secretion in short children, remaining, however, discordant with the results of GH stimulating tests and with IGF-I secretion.

Do IGF-I concentrations better reflect growth hormone (GH) action in children with short stature than the results of GH stimulating tests? Evidence from the simultaneous assessment of thyroid function

Background

The diagnosis of growth hormone (GH) deficiency (GHD) in short children seems unquestionable when both GH peak in stimulating tests (GHST) and IGF-I concentration are decreased. However, the discrepancies between the results of GHST and IGF-I secretion are observed. It seems purposeful to determine the significance of GHST and IGF-I assessment in diagnosing GHD. The relationship between GH secretion and thyroid function, as well as GH influence on the peripheral thyroxine (T₄) to triiodothyronine (T₃) deiodination, mediated by IGF-I, were identified. Thus, clear differences in thyroid function between GH-deficient and non-GH-deficient subjects should exist.

Methods

Analysis comprised 800 children (541 boys), age 11.6 ± 3.1 years (mean ± SD), with short stature, in whom two (2) standard GHST (with clonidine and with glucagon) were performed and IGF-I, free T₄ (FT₄), free T₃ (FT₃) and TSH serum concentrations were assessed. The patients were qualified to the following groups: GHD - decreased GH peak in GHST and IGF-I SDS (n = 81), ISS - normal GH peak and IGF-I SDS (n = 347), low GH - normal IGF-I SDS, and decreased GH peak (n = 212), low IGF - decreased IGF-I SDS, and normal GH peak (n = 160). The relationships among the results of particular tests were evaluated.

Results

In the groups with decreased IGF-I concentrations (GHD Group and low IGF Group), the more severe deficit of height was observed, together with higher TSH and FT₄ but lower FT₃ levels than in groups with normal IGF-I concentrations (ISS Group and low GH Group), independently of the results of GHST. TSH, FT₄ and FT₃ concentrations were - respectively - similar in two groups with decreased IGF-I secretion, as well as in two groups with normal IGF-I levels. Significant correlations were found between patients' height SDS and IGF-I SDS, between FT₃ and IGF-I SDS (positive), and between FT₄ and IGF-I SDS (negative), with no correlation between GH peak and any of the parameters analyzed.

Conclusion

The assessment of thyroid function in children with short stature provides the evidence that measurement of IGF-I concentration may be a procedure reliable at least to the some degree in diagnosing GHD as the results of GHST.

Thyroid function in children with growth hormone (GH) deficiency during the initial phase of GH replacement therapy - clinical implications

Background

Normal thyroid hormone secretion or appropriate L-thyroxine (L-T₄) substitution is necessary for the optimal effect of the growth hormone (GH) administration on growth rate. The decrease of free thyroxine (FT₄) levels at recombinant human GH (rhGH) therapy onset has been reported in several studies. The aim of the present study was to evaluate the effect of rhGH administration on thyrotropin (TSH) and FT₄ serum concentrations in children with GH deficiency (GHD) during the 1st year of therapy, as well as to assess potential indications to thyroid hormone supplementation in them.

Patients and methods

The analysis involved data of 75 children (59 boys, 16 girls) with disorders of GH secretion (GHD, neurosecretory dysfunction - NSD) and partial GH inactivity (inactGH), who were treated with rhGH for - at least - one year. In all the children, body height and height velocity (HV) were assessed before and after 1 year of therapy, while TSH, FT₄, IGF-I and IGFBP-3 before treatment and after 3-6 months and 1 year of treatment. In the patients, who revealed hypothyroidism (HypoT), an appropriate L-T₄ substitution was introduced immediately. The incidence of HypoT, occurring during the initial phase of rhGH therapy, was assessed, as well as its influence on the therapy effectiveness.

Results

Before rhGH substitution, there were no significant differences in either auxological indices or TSH and FT₄ secretion, or IGF-I concentration and its bioavailability among the groups of patients. During the initial 3-6 months of rhGH administration, a significant decrease of FT₄ serum concentration, together with a significant increase of IGF-I SDS and IGF-I/IGFBP-3 molar ratio was observed in all the studied groups. In 17 children, HypoT was diagnosed and L-T₄ substitution was administered. Despite similar IGF-I secretion increase, the improvement of HV presented significantly lower in children with HypoT than in those who remained euthyroid all the time.

Conclusions

The incidence of HypoT during the initial phase of GH treatment in children with GHD and the negative effect of even transient thyroid hormone deficiency on the growth rate should be taken into account.

Metabolic syndrome components among children born small for gestational age: analysis of the first decade of life

INTRODUCTION AND AIM OF THE STUDY

In children born small for gestational age (SGA), some of the metabolic syndrome (MS) components are observed. The goal of the study was an evaluation of the incidence of particular components of MS in 5-9-years-old SGA children.

MATERIAL AND METHODS

Ninety-one prepubertal SGA children (34 boys and 57 girls) were qualified into the study, aged 4.78-9.75 yrs (6.9±1.37 yrs). In each child, the actual height, weight and waist circumference, as well as blood pressure were measured. Fasting triglyceride and HDL-cholesterol levels were assessed. Glucose and insulin concentrations were estimated at fasting state and during the oral glucose tolerance test (OGTT). On the basis of the obtained results, BMI SDS, waist-to-height ratio and the insulin resistance indices (IRI), as defined by HOMA and Belfiore, were calculated.

RESULTS

Visceral obesity was diagnosed in 14 cases, out of which, 5 cases additionally presented with, at least, two other components of MS, while in 5 other cases, one component of MS was additionally confirmed, most frequently as arterial hypertension (HA). In all the analysed SGA children, normal glucose tolerance was observed. Insulin resistance was identified in 13 children, acc. to IRIBelfiore, but not in any child, acc. to IRIHOMA. HA was diagnosed in 30 (33%) prepubertal SGA children, emphasising the fact that its concomitance with visceral obesity was observed in a half of the cases only. Children with HA were taller and heavier, more frequently demonstrating insulin resistance.

CONCLUSIONS

In 5-9-year-old SGA children, a high frequency of particular diagnostic criteria for the MS is observed.

High repeatability of circadian prolactin rhythm assessment results in children

OBJECTIVES

In normal conditions, prolactin (Prl) secretion manifests a circadian pattern. So far, there have only been but few studies, concerning intrasubject variability and repeatability of the circadian Prl secretion pattern, based on pulse analysis. It seems, that macroscopic analysis based on measurement of Prl concentration at nine time points every 3 hours during 24 hours is an appropriate method to assess Prl profile for clinical purposes. The aim of the study was to assess the repeatability of that circadian Prl secretion pattern in a group of short children without hormonal disorders.

MATERIALS AND METHODS

The analysis comprised the results of two circadian Prl profiles, performed from 2 to 14 months in 23 prepubertal children (16 boys) with idiopathic short stature, aged: 10.3+/-2.4 yrs.

RESULTS

There were no statistical differences between Prl concentrations at the same time points in the two consecutive profiles, but the comparison of Prl concentrations at 8:00 gave results which were close to the border of statistical significance (p=0.055), what indicated low repeatability of measurement results at that particular time point. There were no statistical differences between the values of particular parameters in macroscopic profile analysis in the first and in the second test.

CONCLUSION

Circadian Prl profile, based on nine Prl concentration measurements, taken every 3 hours during one day, is characterized by high repeatability of the results and low intrasubject variability in children, despite the results of Prl concentration at 08:00 o'clock.

Effects of one-year low-dose growth hormone (GH) therapy on body composition, lipid profile and carbohydrate metabolism in young adults with childhood-onset severe GH deficiency confirmed after completion of growth promotion

INTRODUCTION

The symptoms of GH deficiency (GHD) in adults include: abnormalities in body composition, unfavourable lipid profile, early atherosclerosis and impaired quality of life. The aim of the study was the selection of patients with confirmed severe GHD from among all the children treated due to GHD, who could benefit from GH therapy continuation in adulthood and the optimization of GH dosage in young adults with severe GHD.

MATERIAL AND METHODS

The study group consisted of 54 young adults (38 male), age 17.6 +/- 1.5 years, with childhood-onset GHD, who had reached final height. At least 1 month after the GH therapy withdrawal, the second evaluation of GH secretion was performed in all the patients. In 24% of patients, permanent severe GHD (PSGHD) was confirmed, but a group of 9 patients (4 male) was involved in renewed GH therapy.

RESULTS

The renewed GH therapy gave positive effects, including a significant increase in fat-free mass and a decrease in fat mass, and a significant decrease in LDL-cholesterol, but connected with an insignificant decrease of HDL-cholesterol serum concentration and improved results of quality of life (QoL) assessment. During the therapy, an insignificant increase of fasting insulin was observed, with no change in fasting glucose and only a slight increase in HbA(1c) percentage. A decrease of insulin sensitivity was also observed, but both insulin secretion and the values of insulin resistance indices still remained within the reference range.

CONCLUSIONS

The observed positive effects on body composition, lipid metabolism and QoL, together with the absence of adverse events, confirm the indications for GH therapy in young adults with severe GHD.

Association of Trp64Arg polymorphism of beta3-adrenergic receptor with insulin resistance in Polish children with obesity

AIM

To establish the influence of the Trp64Arg variant of the beta3-adrenergic receptor (Trp64Arg- beta3AR) on body mass index (BMI) and insulin resistance (IR) in obese children.

METHODS

BMI, presence of the Trp64Arg mutation, plasma glucose and insulin concentrations during an oral glucose tolerance test (OGTT) and IR were determined in 60 obese and 33 normal weight children.

RESULTS

The frequency of Trp64Arg was similar in normal weight and obese children. BMI, glucose and insulin concentrations during an OGTT in children with Trp64Argbeta3AR were not different from those with Trp64Trpbeta3AR. IR was confirmed in 42.8% of children with Trp64Argbeta3AR and in 45.6% of children with Trp64Trpbeta3AR (NS).

CONCLUSIONS

1. The similar frequency of the Trp64Argbeta3AR variant in normal weight and obese children suggests that it is not a susceptibility gene for obesity in Polish children. 2. The presence of the Trp64Argbeta3AR variant does not have an unfavourable influence on BMI, glucose or insulin concentrations during OGTT or on IR frequency in Polish obese children.

Circadian pattern of prolactin secretion in children with growth hormone deficiency and congenital organic lesions in the hypothalamic-pituitary region

OBJECTIVES

Prolactin (Prl) secretion in children manifests circadian rhythm. The aim of the study was to assess circadian Prl pattern in children with growth hormone deficiency (GHD) and congenital organic disorders in the hypothalamic-pituitary region (HPR).

MATERIAL AND METHODS

The analysis comprised 47 children (aged: 11.05+/-3.5 years) with GHD, divided (based on MRI) into subgroups: NORM (no disturbances in HPR); HP (pituitary hypoplasia) and PSIS (pituitary stalk interruption syndrome). The profile of circadian Prl secretion was determined, based on Prl measurements in serum every 3 hours during 24 hours. The macroscopic analysis of circadian Prl rhythm in particular groups was performed. The comparison group consists of 41 children (aged: 11.45+/-3.20 years) with idiopathic short stature (ISS).

RESULTS

In GHD-HP, diurnal and nocturnal Prl concentrations were low but with the dispersion between them and with normal rhythm in most of cases. In GHD-PSIS, diurnal and nocturnal Prl concentrations were on the same level and the rhythm was not observed in most of cases. No significant differences were found in Prl secretions and Prl rhythm between GHD-NORM and ISS. The rhythm of Prl secretion was disturbed in: 72.7% of children with GHD-PSIS, 23.5% - with GHD-HP, 10.5% with GHD-NORM and 7.3% with ISS, only.

CONCLUSIONS

Congenital organic lesions of HPR are associated with quantitative disorders and changes of the circadian pattern of Prl secretion. In children with GHD without organic lesions of HPR, the circadian rhythm of Prl secretion was not different from that with ISS.