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ABALI, SAYGIN/0000-0001-6552-2801; Turan, Serap/0000-0002-5172-5402; Hatun, Sukru/0000-0003-1633-9570; Akgun, Abdurrahman/0000-0002-2917-2469; yesiltepe mutlu, gul/0000-0003-3919-7763; Ozgen, Ilker Tolga/0000-0001-6592-9652 WOS: 000451667000006 PubMed: 29789274 Objective: To assess the incidence of type I diabetes mellitus (T1DM) in children under 18 years of age in the northwest region of Turkey during 2013-2015. Methods: All newly diagnosed T1DM cases were recorded prospectively during 2013-2015. Total, as well as gender and age group specific (0-4, 5-9. 10-14 and 15-17 age) mean incidences per 100,000 per year were calculated. Results: There were 1,773 patients diagnosed during 2013-2015 (588 cases in 2013, 592 cases in 2014, 593 cases in 2015). Of these, 862 (48.6 %) were girls and 911 (51.4%)were boys. The mean age at diagnosis was 9.2 +/- 4.2 years and it was not significantly different between girls (9.0 +/- 4.1 years) and boys (9.4 +/- 4.4 years) (p = 0.052). The crude mean incidence was 8.99/100.000 confidence interval (CI) (95% CI: 8.58-9.42). Although mean incidence was similar between boys [8.98/100.000 (CI: 8.40 to 9.58)] and girls [9.01/100.000 (CI: 8.42 to 9.63)], there was male predominance in all groups except for 5-9 year age group. The standardized mean incidence was 9.02/100.000 according to the World Health Organization standard population. The mean incidence for the 0-4, 5-9, 10-14 and 15-17 age groups was 6.13, 11.68, 11.7 and 5.04/1 00.000 respectively. The incidence of T1DM was similar over the course of three years (p = 0.95). A significant increase in the proportion of cases diagnosed was observed in the autumn-winter seasons. Conclusion: The northwest region of Turkey experienced an intermediate incidence of T1DM over the period of the study.

siklar, zeynep/0000-0003-0921-2694; ABALI, SAYGIN/0000-0001-6552-2801; Turan, Serap/0000-0002-5172-5402; UCAKTURK, Seyit Ahmet/0000-0001-8666-4454; yesiltepe mutlu, gul/0000-0003-3919-7763; Demir, Korcan/0000-0002-8334-2422; Hatun, Sukru/0000-0003-1633-9570 WOS: 000487006600007 PubMed: 31099079 Aims To describe the baseline clinical and laboratory findings and treatment modalities of 367 children and adolescents diagnosed with Type 2 diabetes in various paediatric endocrinology centres in Turkey. Methods A standard questionnaire regarding clinical and laboratory characteristics at onset was uploaded to an online national database system. Data for 367 children (aged 6-18 years) newly diagnosed with Type 2 diabetes at 37 different paediatric endocrinology centres were analysed. Results After exclusion of the children with a BMI Z-score < 1 SD, those with genetic syndromes associated with Type 2 diabetes, and those whose C-peptide and/or insulin levels were not available, 227 cases were included in the study. Mean age was 13.8 +/- 2.2 (range 6.5-17.8) years, with female preponderance (68%). Family history of Type 2 diabetes was positive in 86% of the children. The mean BMI was 31.3 +/- 6.5 kg/m(2) (range 18.7-61) and BMI Z-score was 2.4 +/- 0.8 (range 1-5). More than half (57%) of the children were identified by an opportunistic diabetes screening due to existing risk markers without typical symptoms of diabetes. Only 13% (n = 29) were treated solely by lifestyle modification, while 40.5% (n = 92) were treated with metformin, 13% (n = 30) were treated with insulin, and 33.5% (n = 76) were treated with a combination of insulin and metformin initially. Mean HbA(1C) levels of the insulin and combination of insulin and metformin groups were 98 (11.1%) and 102 mmol/mol (11.5%), respectively, and also were significantly higher than the lifestyle modification only and metformin groups mean HbA(1C) levels (70(8.6%) and 67 mmol/mol (8.3%), respectively). Conclusions An opportunistic screening of children who are at high risk of Type 2 diabetes is essential, as our data showed that > 50% of the children were asymptomatic at diagnosis. The other important result of our study was the high rate of exclusion from the initial registration (38%), suggesting that accurate diagnosis of Type 2 diabetes in youth is still problematic, even for paediatric endocrinologists.

Context The clinical effects of classical 3β-hydroxysteroid dehydrogenase 2 (3βHSD2) deficiency are insufficiently defined due to a limited number of published cases. Objective To evaluate an integrated steroid metabolome and the short- and long-term clinical features of 3βHSD2 deficiency. Design Multicenter, cross-sectional study. Setting Nine tertiary pediatric endocrinology clinics across Turkey. Patients Children with clinical diagnosis of 3βHSD2 deficiency. Main Outcome Measures Clinical manifestations, genotype-phenotype-metabolomic relations. A structured questionnaire was used to evaluate the data of patients with clinical 3βHSD2 deficiency. Genetic analysis of HSD3B2 was performed using Sanger sequencing. Novel HSD3B2 mutations were studied in vitro. Nineteen plasma adrenal steroids were measured using LC-MS/MS. Results Eleven homozygous HSD3B2 mutations (6 novel) were identified in 31 children (19 male/12 female; mean age: 6.6 ± 5.1 yrs). The patients with homozygous pathogenic HSD3B2 missense variants of > 5% of wild type 3βHSD2 activity in vitro had a non-salt–losing clinical phenotype. Ambiguous genitalia was an invariable feature of all genetic males, whereas only 1 of 12 female patients presented with virilized genitalia. Premature pubarche was observed in 78% of patients. In adolescence, menstrual irregularities and polycystic ovaries in females and adrenal rest tumors and gonadal failure in males were observed. Conclusions Genetically-documented 3βHSD2 deficiency includes salt-losing and non-salt–losing clinical phenotypes. Spared mineralocorticoid function and unvirilized genitalia in females may lead to misdiagnosis and underestimation of the frequency of 3βHSD2 deficiency. High baseline 17OHPreg to cortisol ratio and low 11-oxyandrogen concentrations by LC-MS/MS unequivocally identifies patients with 3βHSD2 deficiency.

Background: Deficient glucocorticoid biosynthesis leading to adrenal insufficiency is life-threatening and is associated with significant co-morbidities. The affected pathways underlying the pathophysiology of co-morbidities due to glucocorticoid deficiency remain poorly understood and require further investigation. Methods: To explore the pathophysiological processes related to glucocorticoid deficiency, we have performed global transcriptional, post-transcriptional and metabolic profiling of a cortisol-deficient zebrafish mutant with a disrupted ferredoxin (fdx1b) system. Findings: fdx1b(-/-) mutants show pervasive reprogramming of metabolism, in particular of glutamine-dependent pathways such as glutathione metabolism, and exhibit changes of oxidative stress markers. The glucocorticoid-dependent post-transcriptional regulation of key enzymes involved in de novo purine synthesis was also affected in this mutant. Moreover, fdx1b(-/-) mutants exhibit crucial features of primary adrenal insufficiency, and mirror metabolic changes detected in primary adrenal insufficiency patients. Interpretation: Our study provides a detailed map of metabolic changes induced by glucocorticoid deficiency as a consequence of a disrupted ferredoxin system in an animal model of adrenal insufficiency. This improved pathophysiological understanding of global glucocorticoid deficiency informs on more targeted translational studies in humans suffering from conditions associated with glucocorticoid deficiency. (C) 2018 The Authors. Published by Elsevier B.V. Marie Curie Intra-European FellowshipsEuropean Union (EU) [PIEF-GA-2013-625827]; HGF-programme BIFTM; Deutsche ForschungsgemeinschaftGerman Research Foundation (DFG) [ZUK 40/2010-3009262]; BBSRCBiotechnology and Biological Sciences Research Council (BBSRC) [BB/L010488/1] Marie Curie Intra-European Fellowships for Career Development (PIEF-GA-2013-625827, MISTRAL; to MW), HGF-programme BIFTM (to TD, BG, BL), Deutsche Forschungsgemeinschaft (grant ZUK 40/2010-3009262; to RH and GP) and BBSRC (BB/L010488/1; to FM). The funders had no role in study design, data collection, data analysis, interpretation, or writing of the report. WOS:000447685300042 30266295 Q1

WOS: 000351307200006, PubMed ID: 25800474, Objective: Approaches to diagnosis and treatment of growth hormone deficiency (GHD) in children vary among countries and even among centers in the same country. This survey, aiming to facilitate the process of preparing the new consensus on GHD by the Turkish Pediatric Endocrinology and Diabetes Society, was designed to evaluate the current practices in diagnosis and treatment of GHD in different centers in Turkey. Methods: A questionnaire covering relevant items for diagnosis and treatment of GHD was sent out to all pediatric endocrinology centers. Results: Twenty-four centers returned the questionnaire. The most frequently used GH stimulation test was L-dopa, followed by clonidine. Eighteen centers used a GH cut-off value of 10 ng/mL for the diagnosis of GHD; this value was 7 ng/mL in 4 centers and 5 ng/mL in 2 centers. The most frequently used assay was immunochemiluminescence for determination of GH, insulin-like growth factor-1 and insulin-like growth factor binding protein-3 concentrations. Sex steroid priming in both sexes was used by 19 centers. The most frequently used starting dose of recombinant human GH (rhGH) in prepubertal children was 0.025-0.030 mg/kg/day and 0.030-0.035 mg/kg/day in pubertal children. Growth velocity was used in the evaluation for growth response to rhGH therapy in all centers. Anthropometric measurements of patients every 3-6 months, fasting blood glucose, bone age and thyroid panel evaluation were used by all centers at follow-up. Main indications for cessation of therapy were decreased height velocity and advanced bone age. Fourteen centers used combined treatment (rhGH and gonadotropin-releasing analogues) to increase final height. Conclusion: Although conformity was found among centers in Turkey in current practice, it is very important to update guideline statements and to modify, if needed, the approach to GHD over time in accordance with new evidence-based clinical studies.

BACKGROUND Recent identification and characterization of novel renal Mg(2+) transporters and ion channels have greatly increased our understanding of the normal physiology of renal magnesium handling. METHODS The present study deals with the clinical and molecular characterization of eight Turkish children (median age 10.6 years, range 3-16.2 years, five boys and three girls) with primary hypomagnesaemia from six families. RESULTS All patients initially presented with tetany and convulsions. Laboratory evaluation yielded severely low serum magnesium levels and low serum calcium levels in all patients. While six patients exhibited inadequately low parathyroid hormone levels, the two remaining patients showed hyperparathyroidism, hypercalciuria and nephrocalcinosis. Genetic studies revealed familial hypomagnesaemia with secondary hypocalcaemia (HSH) due to a TRPM6 mutation in six patients and familial hypomagnesaemia with hypercalciuria and nephrocalcinosis (FHHNC) due to a CLDN16 mutation in one patient. CONCLUSIONS Among recently identified magnesium-wasting disorders, HSH and FHHNC represent two major entities also in the Turkish population. Besides clinical course and laboratory diagnosis of hypomagnesaemia, the detection of renal calcium wasting and parathyroid function are crucial to differentiate between these most prevalent forms of hereditary magnesium deficiency. While TRPM6 mutations underlying HSH almost uniformly lead to a complete loss of function of the TRPM6 protein, the severity of FHHNC phenotype depends on the residual function of the mutated claudin-16 protein.

An autosomal recessive form of hypophosphatemia (ARHP) was recently shown to be caused by homozygous mutations in DMP1, the gene encoding dentin matrix protein-1 (DMP-1), a non-collagenous bone matrix protein with an important role in the development and mineralization of bone and teeth. Here, we describe a previously not reported consanguineous ARHP kindred in which the three affected individuals carry a novel homozygous DMP-1 mutation. The index case presented at the age of 3 years with bowing of his legs and showed hypophosphatemia due to insufficient renal phosphate retention. Serum alkaline phosphatase activity was elevated, with initially normal PTH. FGF23 was inappropriately normal at an older age while being treated with oral phosphate and 1,25(OH)(2)D. Similar clinical and biochemical findings, except for elevated FGF23 levels, were present in his 16-month-old brother and his 12.5-year-old female cousin; the parents of the three affected children are first-degree cousins. Nucleotide sequence analysis was performed on PCR-amplified exons encoding DMP-1 and flanking intronic regions. A novel homozygous frame-shift mutation (c.485Tdel; p.GLu163ArgfsX53) in exon 6 resulting in a premature stop codon was identified in all effected individuals. The parents and available unaffected siblings were heterozygous for c.485Tdel. Tooth growth and shape were normal for the index case, his affected brother and cousin, but their permanent and deciduous teeth displayed enlarged pulp chambers. The identified genetic mutation underscores the importance of DMP-1 mutations in the pathogenesis of ARHP. Furthermore, DMP-1 mutations appear to contribute, through yet unknown mechanisms, to tooth development. (C) 2009 Elsevier Inc. All rights reserved.

PubMedID: 19755480 Context: The neurokinin B (NKB) receptor, encoded by TACR3, is widely expressed within the central nervous system, including hypothalamic nuclei involved in regulating GnRH release. We have recently reported two mutations in transmembrane segments of the receptor and a missense mutation in NKB in patients with normosmic isolated hypogonadotropic hypogonadism (nIHH). Patients and Methods:Wesequenced the TACR3 gene in a family in which three siblings had nIHH. The novel mutant receptor thus identified was studied in a heterologous expression system using calcium flux as the functional readout. Results: All affected siblingswerehomozygousfor the His148Leu mutation, in the first extracellular loop of theNKB receptor. The His148Leu mutant receptor exhibited profoundly impaired signaling in response to NKB (EC50 = 3 ± 0.1 nM and >5 µM for wild-type and His148Leu, respectively). The location of the mutation in an extracellular part of the receptor led us also to test whether senktide, a synthetic NKB analog, may retain ability to stimulate the mutant receptor. However, the signaling activity of the His148Leu receptor in response to senktide was also severely impaired (EC50 = 1 ± 1 nM for wild-type and no significant response of His148Leu to 10 µM). Conclusions: Homozygosity for the TACR3 His148Leu mutation leads to failure of sexual maturation in humans, whereas signaling by the mutant receptor in vitro in response to either NKB or senktide is severely impaired. These observations further strengthen the link between NKB, the NKB receptor, and regulation of human reproductive function. Copyright © 2009 by The Endocrine Society.

Background: To characterize cathepsin K (CTSK) mutations in a group of patients with pycnodysostosis, who presented with either short stature or atypical fractures to pediatric endocrinology or dysmorphic features to pediatric genetics clinics. Methods: Seven exons and exon/intron boundaries of CTSK gene for the children and their families were amplified with PCR and sequenced. Sixteen patients from 14 families with pycnodysostosis, presenting with typical dysmorphic features, short stature, frequent fractures and osteosclerosis, were included in the study. Results: We identified five missense mutations (M1I, I249T, L7P, D80Y and D169N), one nonsense mutation (R312X) and one 301 bp insertion in intron 7, which is revealed as Alu sequence; among them, only L7P and I249 were described previously. The mutations were homozygous in all cases, and the families mostly originated from the region where consanguineous marriage rate is the highest. Patients with M1I mutation had fractures, at younger ages than the other pycnodysostosis cases in our cohort which were most probably related to the severity of mutation, since M1I initiates the translation, and mutation might lead to the complete absence of the protein. The typical finding of pycnodysostosis, acroosteolysis, could not be detected in two patients, although other patients carrying the same mutations had acroosteolysis. Additionally, none of the previously described hot spot mutations were seen in our cohort; indeed, L7P and R312X were the most frequently detected mutations. Conclusions: We described a large cohort of pycnodysostosis patients with genetic and phenotypic features, and, first Alu sequence insertion in pycnodysostosis.