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.

An Asymptomatic, Ectopic Mass as a Presentation of Adrenocortical Carcinoma Due to a Novel Germline TP53 p.Phe338Leu Tetramerisation Domain Variant.

Adrenocortical carcinoma (ACC) is a rare cancer in childhood. ACC is frequently associated with germline TP53 variants, with founder effects especially due to the p.Arg337His mutation. ACC leads to the secretion of adrenocortical hormones, resulting in endocrine syndromes, which is the usual trigger for establishing the diagnosis. We present a surprising ACC pathology in a non-secreting, ectopic retroperitoneal tumour in a 4-year-old boy, successfully controlled with chemotherapy and mitotane after microscopically incomplete tumour resection with spillage. Genomic analysis (gene panel sequencing and copy-number microarray) demonstrated a novel p.Phe338Leu tetramerisation domain (TD) TP53 variant in the proband and his cancer-free mother and a monoallelic deletion encompassing the TP53 locus in cancer tissue, consistent with cancer-predisposition syndrome. While the recurrent p.Arg337His variant translates into high ACC risk, residue 338 and, in general, TD domain variants drive heterogeneous clinical scenarios, despite generally being considered less disruptive than TP53 DNA-binding domain mutations.

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.

Delayed Diagnosis of Congenital Combined Pituitary Hormone Deficiency including Severe Growth Hormone Deficiency in Children with Persistent Neonatal Hypoglycemia-Case Reports and Review.

Apart from stimulation of human growth and cell proliferation, growth hormone (GH) has pleiotropic metabolic effects in all periods of life. Severe GH deficiency is a common component of combined pituitary hormone deficiency (CPHD). CPHD may be caused by mutations in the genes encoding transcription factors and signaling molecules involved in normal pituitary development; however, often its genetic cause remains unknown. Symptoms depend on which hormone is deficient. The first symptom of GH or adrenocorticotropic hormone (ACTH) deficiency may be persistent hypoglycemia in apparently healthy newborns, which is often neglected. Diagnosing CPHD is based on decreased concentrations of hormones secreted by the anterior pituitary and peripheral endocrine glands. Findings in magnetic resonance imaging vary widely, including anterior pituitary hypoplasia/aplasia or pituitary stalk interruption syndrome (PSIS). Delayed diagnosis and treatment can be life-threatening. GH therapy is necessary to recover hypoglycemia and to improve auxological and psychomotor development. We present two girls, diagnosed and treated in our departments, in whom the diagnosis of CPHD was delayed, despite persistent neonatal hypoglycemia; and a review of similar cases, with attention paid to progress in the genetic assessments of such patients, since the introduction of whole exome sequencing that is especially important for PSIS.

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.

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 IGFGT 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.

Seasonality of vitamin D concentrations and the incidence of vitamin D deficiency in children and adolescents from central Poland.

INTRODUCTION: Vitamin D3 [25(OH)D] deficiency is a significant problem in Polish children. In many regions of the world, 25(OH)D concentrations show seasonal variation and differences between boys and girls, due to seasonal differences in insolation, as well as different sociological and cultural factors. THE AIM OF THE STUDY: The aim of the study was to assess the seasonal variations of 25(OH)D concentrations and the incidence of vitamin D deficiency in children from central Poland. MATERIAL AND METHODS: The analysis comprised 1275 children, age 3-18 (11.2 ±4.0) years, with disorders of growing and/or puberty, obesity, and other complaints that could be related to endocrine diseases, except for ones with calcium-phosphorus imbalance, impaired parathyroid hormone secretion, and diseases that may influence vitamin D supply. RESULTS: Seasonal variability of 25(OH)D concentrations was observed with maximal levels in August and minimal in January and close relationship between 25(OH)D levels and insolation in the previous two months. In all the quarters, 25(OH)D concentrations were lower in girls than in boys and in older vs. younger children. The median value of 25(OH)D concentrations was below the lower limit of optimal range during the whole year. High incidence of 25(OH)D deficiency was observed (from 10.7% in August to 80.4% in January) together with low proportion of normal 25(OH)D levels (from 3.6% in January to 42.1% in August). CONCLUSIONS: Our results are consistent with previous reports on inadequate vitamin D supplementation in Polish children and adolescents, pointing out the necessity to implement current recommendations concerning vitamin D supplementation and the need for further studies on the consequences vitamin D deficiency for health of children and adolescents, with special attention to the pleiotropic effects of vitamin D.

Treatment of severe primary IGF-1 deficiency using rhIGF-1 preparation - first three years of Polish experience.

INTRODUCTION: The objective of this study was to analyse the effects of the first three years of treatment with recombinant human insulinlike growth factor 1 (rhIGF-1) in patients from the Polish population. MATERIAL AND METHODS: Twenty-seven children (22 boys and five girls) aged 2.8 to 16.0 years old were qualified for treatment with rhIGF-1 (mecasermin) in different treatment centres, according to Polish criteria: body height below -3.0 SD and IGF-1 concentration below percentile 2.5 with normal growth hormone (GH) levels. Mecasermin initial dose was 40 µg/kg bw twice a day and was subsequently increased to an average of 100 µg/kg bw twice a day. Body height, height velocity, weight, body mass index (BMI), and adverse events were measured. RESULTS: Mecasermin treatment resulted in a statistically significant increase in body height (1.45 ± 1.06 SD; p < 0.01) and height velocity in comparison with pre-treatment values. The biggest change in height velocity happened during the first year and diminished during subsequent years. Body weight and BMI also increased significantly after treatment (1.16 ± 0.76 SD and 0.86 ± 0.75 SD, respectively; p < 0.01). Eight patients reported adverse events. These were mild and temporary and did not require treatment modification except in two patients. CONCLUSIONS: Treatment with rhIGF-1 was effective and safe in Polish patients with primary IGF-1 deficiency. It had a clear beneficial effect on the height of the patients and significantly accelerated the height velocity, particularly in the first year of treatment.

Management of Prader-Willi Syndrome (PWS) in adults - what an endocrinologist needs to know. Recommendations of the Polish Society of Endocrinology and the Polish Society of Paediatric Endocrinology and Diabetology.

Prader-Willi syndrome (PWS) is a complex genetic disorder characterised by a set of phenotypic traits, which include infantile hypotonia, short stature, and morbid obesity. Over the last 12 years, visible progress has been made in medical care management of PWS patients in Poland. Increasing awareness of the disorder in neonatal and paediatric care has led to early identification of the condition in neonates, followed by the institution of an appropriate dietary regime, introduction of physiotherapy, and early-onset recombinant human growth hormone (rhGH) treatment. Growth hormone (GH) therapy in Poland is conducted within the nationwide framework of the Therapeutic Programme: "Treatment of Prader-Willi Syndrome". The therapeutic interventions initiated in the paediatric centres need to be continued in multidisciplinary adult care settings. The main aim of PWS clinical management in adulthood is prevention of obesity and its comor-bidities, treatment of hormonal disorders, mental health stabilisation, nutritional guidance, as well as on-going physiotherapy. Integrated multidisciplinary therapeutic intervention is necessary if patients with such a complex genetic condition as PWS are to not only achieve an average life expectancy but also to enjoy higher quality of life.

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.

Nutritional Status in Short Stature Children Is Related to Both Ghrelin and Insulin-like Growth Factor I Concentrations.

OBJECTIVES: Ghrelin plays an important role in the growth processes in children. In addition, it regulates appetite. The aim of the study was to assess ghrelin and insulin-like growth factor type I (IGF-I) concentrations in children with idiopathic short stature, dependent on nutritional status. METHODS: The study group included 116 children, ages 10.6 ±â€Š3.5 years (mean ±â€Šstandard deviation), with idiopathic short stature (height <-2.0 standard deviation scores [SDS], maximal growth hormone [GH] secretion during 2 GH-stimulating tests->10 ng/mL). In each child, fasting ghrelin, IGF-I, insulin-like growth factor binding protein 3 (IGFBP-3), glucose, insulin, lipids, leptin, adiponectin, and resistin concentrations were assessed. The IGF-I/IGFBP-3 molar ratio was calculated to determine the IGF-I bioavailability. According to body mass index SDS calculated for height age, the children were divided into 3 groups: poorly nourished (thin), normal, and obese. The control group consisted of 19 healthy children, ages 11.0 ±â€Š3.5 years, with normal body weight and height. RESULTS: Ghrelin concentration was significantly higher in short, thin children than in short, obese children (1458.3 ±â€Š798.5 vs 917.2 ±â€Š303.0 pg/mL; P < 0.005). In turn, IGF-I/IGFBP-3 molar ratio was significantly lower in short, thin children than in short, obese children (0.16 ±â€Š0.06 vs 0.28 ±â€Š0.15; P < 0.005). CONCLUSIONS: In short, thin children, despite elevated ghrelin production, the low IGF-I concentration is observed, probably due to undernutrition and worse IGF-I formation. In short, normal-weight children and in short, obese ones, ghrelin and IGF-I production is normal, and it seems that mechanisms responsible for their short stature are other than low IGF-I.

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.

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.

Autoimmune polyglandular syndrome type 2 manifested as Hashimoto's thyroiditis and adrenocortical insufficiency, in Turner syndrome woman, with onset following introduction of treatment with recombinant human growth hormone.

Autoimmune polyglandular syndrome is a constellation of signs and symptoms of simultaneous insufficiencies of several endocrine glands. Autoimmune polyglandular syndrome type 2 (APS 2) may be diagnosed when the adrenocortical insufficiency is associated with an autoimmune thyroid disease (Hashimoto's thyroiditis or Graves' disease), and/or insulin-dependent diabetes mellitus. Turner syndrome is the most common chromosomal disorder in females, caused by complete or partial X chromosome monosomy. We present the case of a 20-year-old woman with Turner syndrome, in whom APS 2 (Hashimoto's thyroiditis and adrenocortical insufficiency) has been diagnosed after introduction of recombinant human growth hormone (rhGH) therapy. In Turner syndrome, examination of the patient must regularly be conducted in order to diagnose a possible onset of autoimmune diseases; respective treatment must be applied as soon as the diagnosis is established. In particular, therapy of rhGH, used for short stature treatment, may be a trigger factor of adrenal insufficiency. The cortisol level in blood should be assessed before rhGH administration and carefully monitored during the therapy, especially in case of autoimmune thyroid disease coexistence.

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.

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.