Stimulated GH levels during the transition phase in Prader-Willi syndrome.

PURPOSE: Early institution of GH therapy in children with Prader-Willi syndrome (PWS) yields beneficial effects on their phenotype and is associated with a persistent improvement of body composition, both in the transition age and in adulthood. Reports from GH stimulation testing in PWS adults, however, suggest that GH deficiency (GHD) is not a universal feature of the syndrome, and the current Consensus Guidelines suggest to perform a reassessment of persistent GHD so as to continue GH therapy after reaching adult height. Few data about GH responsiveness to stimulation testing throughout the transitional period in PWS are available to date. Thus, we investigated the prevalence of GHD in a large cohort of patients with PWS during the transition phase. PATIENTS AND METHODS: One hundred forty-one PWS patients, 72 females and 69 males, aged 15.4-24.9 years, were evaluated by dynamic testing with growth hormone-releasing hormone (GHRH) plus arginine (GHRH + ARG). To define GHD, both BMI-dependent and BMI-independent diagnostic cut-off limits were considered. RESULTS: According to BMI-dependent criteria, 10.7% of normal weight (NW), 18.5% of overweight and 22.1% of obese PWS maintained a status of GHD. Similar results were obtained by adopting a cut-off limit specific for the adult age (26.2%), as well as criteria for the transition phase in NW subjects (25%). CONCLUSION: Our study shows that about 20% of patients with PWS fulfilled the criteria for GHD during the transitional age, suggesting the need of an integrated analysis of GH/IGF-I axis, in the context of the general clinical picture and other endocrine abnormalities, in all subjects after attainment of final stature.

Disorders of glucose metabolism in Prader-Willi syndrome: Results of a multicenter Italian cohort study.

BACKGROUND AND AIMS: Prader-Willi syndrome (PWS) is characterized by a high incidence of altered glucose metabolism (AGM). However, epidemiological data on impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM) are still discordant. METHODS AND RESULTS: We performed a multicenter study based on 274 PWS patients [144 females, aged 20.3 ± 10.4 yrs (range: 8.1-50.1 years)] evaluating the prevalence for AGM in the entire group, and according to age (children <10 yrs; adolescents 10-18 yrs, and adults >18 yrs), Body Mass Index (BMI = kg/m(2)), gender, genotypes (deletion or uniparental disomy for chromosome 15), and GH therapy (GHT) (untreated, previously or currently treated). Altogether, AGM was detected in 67 (24.4%) of patients (0.7% IFG, 10.2% IGT, 13.5% T2DM). The prevalence of AGM was correlated to age (p = 0.001), BMI (p = 0.001) and HOMA-IR (p = 0.001). However, gender, genotype, and GHT did not influence AGM development in univariate analysis. These data were confirmed as positive predictors when inserted in a multivariate analysis model. CONCLUSION: This study is the first report on the prevalence of AGM in a large population of PWS. Overall, PWS subjects show a high prevalence of AGM that appears more common in obese and adult subjects. Our data confirm the main role of obesity on the individual metabolic risk clustering in PWS, and thus reinforce the concept that improvement in weight control remains the most important goal of any PWS treatment program.

Low mean impedance in 24-hour tracings and esophagitis in children: a strong connection.

Esophageal multiple intraluminal impedance baseline is an additional impedance parameter that was recently related to esophageal integrity. The aim of this study was to assess the relationship between mean esophageal impedance value and endoscopic findings in a large group of children. Children with symptoms of gastroesophageal reflux submitted to both endoscopy and impedance were included. Esophagitis was graded according to the Los Angeles classification. Mean impedance value was automatically calculated over 24-hour tracings. Data were adjusted for age through z-score transformation using percentiles normalized by the LMS (Lambda for the skew, Mu for the median, and Sigma for the generalized coefficient of variation) method. Nonparametric Mann-Whitney and Kruskal-Wallis tests, multiple, and stepwise regression were used. P-value <0.05 was considered as statistically significant. A total of 298 impedance tracings were analyzed. Endoscopic and histological esophagitis were detected in 30 and 29% patients, respectively. Median baseline z-score was significantly decreased both in proximal (P = 0.02) and distal (P = 0.01) esophagus in patients with endoscopic (but not histological) esophagitis. Patients with more severe esophagitis showed the lowest z-score. Bolus exposure index and the number of reflux episodes were the variables that were significantly associated with the baseline z-score. Impedance z-score is significantly decreased in infants and children with endoscopic esophagitis. Severity of esophagitis, bolus exposure index, and number of reflux episodes are factors influencing mean esophageal impedance.

Behind the (impedance) baseline in children.

Impedance baseline is a new parameter recently related to esophageal integrity. The aim of this study was to assess the effect of different factors on impedance baseline in pediatric patients. We analyzed the impedance baseline of 800 children with symptoms of gastroesophageal reflux. Mean impedance baseline was automatically calculated throughout 24-hour tracings. The presence of different age groups and of esophagitis was evaluated. Unpaired t-test, Spearman rank correlation, polynomial, and regression plot were used for statistical analysis. Age-related percentile curves were created. We considered a P-value<0.05 as statistically significant. Impedance baseline was significantly (P<0.001) lower in younger compared to older children up to 48 months. The mean increase of baseline per month was much higher in the first 36 months of life (47.5 vs. 2.9 Ohm in Channel 1 and 29.9 vs. 2.3 Ohm in Channel 6, respectively) than in older ages. Patients with esophagitis showed significantly decreased impedance baseline (P<0.05). Infants (especially in the first months of life) and young children present a significantly lower impedance baseline compared to older children both in proximal and distal esophagus. The presence of esophagitis may also determine a decreased impedance baseline regardless of the age of the patients.

Metabolic syndrome in adult patients with Prader-Willi syndrome.

BACKGROUND AND AIMS: Prader-Willi syndrome (PWS), the most common genetic cause of obesity, is characterized by elevated morbility and mortality in all ages. In this context, non-obese PWS children showed low frequency of metabolic syndrome (MetS), while a comparable prevalence was observed in obese PWS and obese controls. Aim of this study was to estimate the occurrence of MetS and its components in a large group of PWS adults, according to obesity status. METHODS AND RESULTS: A cross-sectional study was performed in 108 PWS aged 18.0-43.2 years (87 obese and 21 non-obese) and in 85 controls with nonsyndromic obesity matched for age, gender, and BMI with obese PWS. Non-obese PWS showed lower waist circumference, insulin, HOMA-index, triglycerides, diastolic blood pressure, and higher HDL-C than both obese PWS and obese controls (p < 0.017). Obese PWS showed higher glucose and systolic blood pressure than both non-obese PWS and obese controls (p < 0.017). MetS was found in 1/21 (4.8%) non-obese PWS, 36/87 (41.4%) obese PWS and 39/85 (45.9%) obese controls. Non-obese PWS showed lower frequency for each MetS component as compared with obese PWS and obese controls. PWS patients with deletion of the chromosome 15q11-13 showed a lower risk for low HDL-C (p < 0.01) and a trend towards a lower MetS risk (p < 0.06) compared to subjects without deletion. CONCLUSION: Our findings suggest the main role that obesity status plays on the individual metabolic risk clustering in PWS adults. Early identification of MetS could be helpful to improve morbidity and prevent mortality in such patients.

Metabolic syndrome in children with Prader-Willi syndrome: the effect of obesity.

BACKGROUND AND AIMS: Prader-Willi syndrome (PWS), the most frequent syndromic obesity, is associated with elevated morbidity and mortality in pediatric and adult ages. In PWS, the presence of metabolic syndrome (MS) has not yet been established. The aim of the study was to estimate the frequency of MS and its components in pediatric subjects according to obesity status. METHODS AND RESULTS: A cross-sectional study was performed in 109 PWS children aged 2-18 years (50 obese and 59 non-obese) and in 96 simple obese controls matched for age, gender, and also for BMI with obese PWS. Obesity was defined when SDS-BMI was >2. Non-obese PWS showed significantly lower frequency of hypertension (12%) than obese PWS (32%) and obese controls (35%)(p=0.003). The same was observed for low HDL-cholesterol (3% vs 18% and 24%, p=0.001) and high triglycerides (7% vs 23% and 16%, p=0.026). Frequency of altered glucose metabolism was not different among groups (2% vs 10% and 5%), but type 2 diabetes (four cases) was present only in obese PWS. Non-obese PWS showed lower insulin and HOMA-index respect to obese PWS and obese controls (p ≤ 0.017). Overall MS frequency in PWS was 7.3%. None of the non-obese PWS showed MS compared with 16% of obese PWS and controls (p<0.001). When obesity was excluded from the analysis, a significantly lower frequency for clustering of ≥ 2 factors was still found in non-obese PWS (p=0.035). CONCLUSION: Non-obese PWS showed low frequency of MS and its components, while that observed in obese PWS was very close to those of obese controls, suggesting the crucial role of obesity status. Prevention of obesity onset remains the most important goal of PWS treatment. Early identification of MS could be helpful to improve morbidity and mortality in such patients.

Esophageal impedance and esophagitis in children: any correlation?

AIM: : The aim of this study was to correlate the data obtained with multiple intraluminal esophageal impedance and pH (MII-pH) recordings in infants and children referred for suspected gastroesophageal reflux disease with esophageal histology. MATERIALS AND METHODS: : In a prospective study, results of esophageal biopsies and MII-pH recording obtained in 45 children (mean age +/- SD: 69 +/- 55 months) were analyzed. Regarding the MII-pH data, an automatic (Autoscan Bioview Analysis Software, version 5.3.4, Sandhill Scientific Inc, Highlands Ranch, CO) and a manual reading were performed; an automatic pH analysis (meal included) was also performed. RESULTS: : Acidic, weakly acidic, and alkaline reflux episodes accounted, respectively, for 48.7%, 49.5%, and 1.8% of the total number of reflux episodes detected by MII-pH. Esophagitis was present in 25 (56%) children. Concordance between classic pH-study analysis (alone) and esophageal histology was found in 19 of 45 (42%) children. According to the MII-pH analysis, the mean and median value of the pH were significantly higher in the group with esophagitis than in the group with normal esophageal histology. A longer clearance time was found in the group with esophagitis than in subjects with normal histology. Gas reflux episodes represented 21% of the total reflux episodes and were comparable in both groups. CONCLUSIONS: : Multiple intraluminal esophageal impedance and pH analysis does not provide a distinct parameter to predict esophageal mucosal injury in children. In our population, MII-pH shows comparable acidic, weakly acidic, alkaline, and gas reflux in children with and without esophagitis. Further research is needed to analyze clearance parameters.

Short-term effects of growth hormone treatment on the upper airways of non severely obese children with Prader-Willi syndrome.

AIMS: The aim of this study was to establish whether short-term GH treatment causes obstructive apnea in patients with Prader-Willi syndrome and normal upper airway patency. SUBJECTS AND METHODS: We performed an observational longitudinal 6-week GH treatment study. Thirty-four non-severely obese Prader-Willi syndrome patients (20 boys, age range 0.94-11.8 yr, median 2.24 yr) entered an observational longitudinal 6-week study. Sixteen boys received recombinant human GH (rhGH) treatment; the remaining 18 represented the control group and received no treatment. Polysomnography monitoring and othorhinolaringoiatric video endoscopy were performed one night before and after 6 weeks of rhGH treatment (0.03 mg/kg body weight/day). All patients underwent auxologic assessment, fasting blood glucose, insulin and IGF-I evaluation. The main polysomnographic parameter considered was total apnea hypopnea index, consisting of two components: central apnea hypopnea index and obstructive apnea hypopnea index. All patients were free of severe or moderate upper airway obstruction when rhGH treatment began. RESULTS: After 6 weeks of rhGH therapy, obstructive apnea hypopnea index increased in 8/16 (50%), decreased in 5/16 (31%), and did not change in 3/16 (19%) patients. The changes were not statistically significant. The rhGH-treated group did not differ from the control group for the apnea hypopnea index both before and after 6 weeks of treatment. Adenoids and tonsils showed a slight increase in 1 and 2 patients on rhGH treatment, respectively, and did not change in the untreated patients. CONCLUSIONS: Our data show that short-term rhGH treatment does not cause restrictions of the upper airways in patients with Prader-Willi syndrome and normal upper airway patency.

A survey on Prader-Willi syndrome in the Italian population: prevalence of historical and clinical signs.

Clinical criteria for the diagnosis of Prader-Willi Syndrome (PWS) were established by consensus in 1993 (Holm et al.). Specific molecular testing is now available and the purpose of diagnostic criteria has shifted to identify individuals to test, thus avoiding the expense of unnecessary analysis. The aim of this study was to find clinical indicators to select patients with suspected PWS for laboratory testing. We analyzed the prevalence of clinical signs and symptoms in 147 genetically diagnosed Italian patients with PWS (67 males and 80 females), aged from 9 months to 34.6 years (13.6 +/- 8.3 years), using the consensus diagnostic criteria, and according to age, sex and type of genetic abnormality. The prevalence of several clinical features changed significantly with age, but very few with sex. According to genetic subtypes (deletion vs UPD), only hypopigmentation and acromicria were more frequent in patients with deletion. Some criteria considered as minor or supportive by Holm et al. have higher prevalence than some major criteria. In conclusion, in order to identify patients with suspected PWS to submit to laboratory testing, we recommend a classification of clinical criteria according to age, giving more attention to those so-called minor or supportive criteria.

Variability of the 13C-octanoic acid breath test for gastric emptying of solids in healthy children.

AIM: To assess the intra-individual variability of the 13C-octanoic acid breath test using non-dispersive infrared spectrometry for gastric emptying of solids in healthy children. METHODS: A 13C-octanoic acid breath test was performed at least two times in 19 healthy children (age 12.4 +/- 2.7 years) 2-7 days apart to measure gastric emptying of solids. Breath samples were taken before eating a 13C-octanoic acid-labelled pancake and at 15-min intervals for the following 240 min. Breath samples were analysed using non-dispersive infrared spectrometry; 13C-recovery was used to calculate values for gastric half-emptying time (t(1/2)), gastric lag phase (t(lag)) and gastric emptying coefficient. Intra-individual variability of the parameters t(1/2), t(lag) and gastric emptying coefficient were expressed as coefficient of intrasubject variation. RESULTS: The mean coefficient of intrasubject variation of t(1/2) was 13.3 +/- 7.9% (range 2.5-29.6%; interindividual range 99-204 min; intra-individual range 5-84 min for t(1/2)). The mean coefficient of intrasubject variation of t(lag) was 13.6 +/- 7.5% (range 0.8-27.8%) (interindividual range 65-146 min; intra-individual range 1-50 min for t(lag)). The mean coefficient of intrasubject variation of gastric emptying coefficient was 12.5 +/- 6.8% (range 3.4-30.2%; interindividual range 2.3-3.9; intra-individual range 0.17-1.4 for gastric emptying coefficient). The coefficient of intrasubject variations of t(1/2), t(lag) and gastric emptying coefficient were independent of the values of t(1/2), t(lag) and gastric emptying coefficient. CONCLUSIONS: Gastric emptying in healthy children is characterized by a large inter- and intra-individual variability and is concordant with the results obtained with other techniques.

A "hot spot" in the Pit-1 gene responsible for combined pituitary hormone deficiency: clinical and molecular correlates.

Pit-1 is a member of the POU family of transcription factors regulating mammalian development. Pit-1 is thought to be the major cell-specific activator of both the somatotrophs and lactotrophs in the anterior pituitary. When bound to DNA, Pit-1 activates GH and PRL gene expression. Pit-1 is also important for hormonal regulation of the PRL and TSH-beta genes by TRH and cAMP. We studied two unrelated patients with GH, PRL, and TSH deficiencies. Both patients have the same point mutation in the POU homeodomain of the Pit-1 gene (R271W). Patient 1 was studied as an adult and had combined deficiencies of GH, PRL, and TSH. Patient 2, who was studied in infancy, also had GH and PRL deficiencies, but had low thyroid hormone levels with a measurable basal level of TSH and a delayed response of TSH to TRH. Consequently, the current description of Pit-1 gene mutations leading to complete GH, PRL, and TSH deficiencies needs to be expanded to GH and PRL deficiencies associated with a compromise of the thyrotroph's ability to synthesize TSH.

Evidence for the presence of the pituitary insulin secretagogue beta-cell trophin in human plasma.

It has been demonstrated that the insulin secretagogue beta-cell-trophin, ACTH(22-39), is present in human plasma. The hormone, separated from plasma by affinity chromatography on a corticotrophin-like intermediate-lobe peptide antibody column, behaves similarly to synthetic beta-cell-trophin on a gel filtration column and on reverse-phase high-performance liquid chromatography. Sufficient amounts of the hormone were isolated from the plasma of two patients with Nelson's syndrome to demonstrate its biological activity on the perfused rat pancreas.

The influence of dietary education in diabetic children.

The aim of our study was to evaluate the efficacy of dietary education in inducing modification of the diet and to measure biochemical parameters in 36 children and adolescents with IDDM. At the beginning of the study, each patient was evaluated as follows: food intake (by the method of the 24-h recall for 3 days), auxological parameters, biochemical parameters. Thereafter a program of nutritional guidelines was provided. Subsequent meetings took place at 1-month-intervals. The study ended 3 months later, when all the parameters were completely revalued. We observed improved nutrition in our patients both in terms of total caloric intake and calorie distribution. In particular there was an increase in carbohydrates and a reduction in lipids, reaching the percentage levels recently recommended. With a reduction in lipid intake a significant decrease in LDL cholesterol and a significant increase in HDL cholesterol were noticed in our patients. These modifications are very important for the prevention of arteriosclerosis and thus macrovascular disease. We maintain that dietary education plays an important role in helping children and adolescents with IDDM to follow a suitable diet.

Multiple pituitary hormone deficiency: management of puberty for optimal auxological results.

The overview in this paper focuses on ways of achieving optimal auxological results in puberty, principally in idiopathic and congenital multiple pituitary hormone deficiency (MPHD), suggested by the co-authors. We agreed that diagnosing gonadotrophin insufficiency/deficiency is difficult in young children and should be repeated in late prepuberty, but a firm diagnosis of MPHD helps avoid endocrine re-testing at the end of growth. The hypothalamic-pituitary axis must be reassessed periodically in evolving endocrinopathies, though current practice varies widely. Optimum age to induce puberty is 11-12 years in girls and 13-14 boys, and sex steroids are the preferred agents. Short-course testosterone to increase micropenis size is advantageous, but inducing early testicular maturation is not known to improve later fertility. There is also little evidence for increasing the dose of GH during puberty, though therapy should continue to final height, and possibly until peak bone mass is achieved. Delaying puberty is an option in septo-optic dysplasia, and minimising the dose of hydrocortisone is crucial in treating ACTH/cortisol insufficiency. Many unresolved questions remain in this difficult area.

Turner's syndrome.

Turner syndrome (TS) is the most common sex-chromosome abnormality in females. Short stature and hypogonadism are the classical clinical findings. The spontaneous final height (FH) ranges between 139 and 147 cm, representing a growth deficit of about 20 cm with respect to the unaffected population. GH therapy improves FH and should be started during childhood at a high dose of about 1 IU/kg/week (range 0.6-2 IU/kg/week). Some authors advocate combined therapy with an anabolic steroid at various doses (e.g. oxandrolone 0.05-0.1 mg/kg/day). This treatment results in a significantly increased FH, a large proportion of treated girls reaching a FH of more than 150 cm. Gonadal function is compromised during adolescence in about 80% of girls with TS, whilst in about 20% pubertal development occurs spontaneously. Oestrogen therapy should be started at the age of 13-14 years in hypogonadic patients; early onset of treatment (before 12 years) seems to compromise FH. Other concerns in these patients are fertility and osteopenia.

Childhood obesity: results of a multicenter study of obesity treatment in Italy.

The prevalence of pediatric obesity is increasing and many patients are followed by specialized centers or private doctors. The aim of this study was to verify short- and medium term results of a therapeutic approach based on nutritional intervention in a large pediatric population: 1383 subjects (695 females, 688 males) aged 10.1 +/- 2.7 yr, followed in 11 pediatric departments in Italy. No difference was found between centers in age, height, weight, BMI and IBW. The drop-out rate after the first visit was 30.2% (58.1% IBW > 140%) in females and 34.2% (70.7% IBW > 140%) in males. After two years of follow-up only 9.7% of females and 6.4% of males remained on treatment. Of these patients only 7.3% of females and 6.4% of males had IBW < 120%. These data show that an approach based on nutritional intervention alone is not sufficient for long-term treatment of pediatric obesity. Only an approach started early and involving the family can produce permanent results.

[Prader-Willi syndrome]. / La sindrome di Prader-Willi.

Prader-Willi syndrome (PWS) is the most frequent cause of secondary obesity, characterized by neonatal hypotonia, dysmorphic facies, acromicria, hypogonadism, stunted growth, obesity, behavioural disturbances and cognitive impairment. Clinical diagnosis is confirmed by alteration of imprinted genes on the proximal long arm of chromosome 15 (15q11-13) for deletion, translocation, uniparental disomy for maternal chromosome 15 or imprinting center defect. Methylation test is the most reliable test for diagnosis. This issue explains diagnostic tests, clinical, metabolic, endocrinological features, and the most frequent complications observed in this syndrome. Precocious diagnosis and multidisciplinary approach allow in these patients to prevent the severe obesity and linked complications.

[Nutrition in school-age children: a survey at a nursery school]. / L'alimentazione nella seconda infanzia: indagine in una scuola materna.

The results of a social-nutritional investigation in a maternal school are reported. Aim of the present study was to evaluate the dietary habits and life style in a group of 3-6 years old children and their compliance in following a diet in accordance with the LARN86 recommendations. The enquiry was carried out by a questionnaire, by an analysis of the ingesta and by a paediatric and auxological examination. Blood and instrumental tests (Lipids panel, Blood glucose, Insulin, Fructosamine, IgE, ECG) were performed in children with high familial risk of atherosclerosis. The main findings were the following: i. 17 children (21%) were classified as having high atherosclerosis familial risk; ii. the atherosclerosis high risk group showed also increased incidence (p less than 0.01) of familial allergy; iii. children had higher approval for food with high carbohydrate and animal protein content; iv. fat intake was proportional to the number of different types of fat bought by the families; v. excessive dietary lipids and low carbohydrate intake were found in most families. The revaluation at the end of the study showed a good compliance for the proposed diet scheme by children, but a poor compliance by their families.

[Intestinal invagination. Analysis of cases]. / L'invaginazione intestinale. Analisi casistica.

16 cases of intussusception, occurred in the last 9 years in the Pediatric Department of the Ospedale di Circolo of Varese, are reported. Barium enema was carried out in 15 cases and the reduction of the intussusception, attempted in 5 of them, was obtained in 3 (20%). The low rate of the attempts of reduction by barium enema is consistently related to a delay in the diagnosis; 56% of the patients showed actually at the diagnosis the three main symptoms simultaneously: abdominal pain, vomiting, "currant jelly stool". The significant positive correlation (p less than 0.01) between the symptoms duration at the diagnosis and the hospitalization period points out that a correct treatment of the intussusception depends mainly on a precocious diagnosis.