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Featured researches published by Feyza Darendeliler.


Acta Paediatrica | 2006

Body mass index references for Turkish children

Rüveyde Bundak; Andrzej Furman; Hülya Günöz; Feyza Darendeliler; Firdevs Bas; Olcay Neyzi

AIM To construct the body mass index reference curves for Turkish children aged 6 to 18 y, and to determine the prevalence of overweight and obesity. SUBJECTS AND METHODS Height and weight measurements of healthy schoolchildren (1,100 boys, 1,019 girls) were obtained biannually. Body mass index was calculated from 11,648 height and weight measurements. Centile curves were constructed using the LMS method. RESULTS The smoothed percentile values and curves for body mass index in Turkish children show that there is a constant increase in body mass index values towards adulthood, especially during the pubertal years, in both sexes. The prevalence of overweight is 25% and obesity 4% in boys at age 18 y. The percentage of overweight and obesity in girls at age 14 was 15% and 1%, respectively. The sample size was too small to come to any conclusion regarding these rates at 18 y of age. CONCLUSION This study presents data and curves for body mass index values in healthy Turkish children aged 6 to 18 y. The values are in compliance with those of Western countries.


Hormone Research in Paediatrics | 2007

Age at Growth Hormone Therapy Start and First-Year Responsiveness to Growth Hormone Are Major Determinants of Height Outcome in Idiopathic Short Stature

Michael B. Ranke; Anders Lindberg; D A Price; Feyza Darendeliler; Kerstin Albertsson-Wikland; Patrick Wilton; Edward O. Reiter

Aim: To develop methods to identify factors associated with a favorable outcome in GH-treated children with idiopathic short stature (ISS). Methods: From 4,685 children listed as having ISS within KIGS (Pfizer International Growth Database), we studied (a) the prediction model group (n = 657) to develop the first-year prediction model, and (b) the near adult height group (NAH; n = 256) which received GH for >4 years to develop descriptive models for adult height and overall height gain. Results: NAH group at GH start: age was 10.0 years, height –2.5 SD score (SDS), weight –2.3 SDS, height minus mid-parental height (MPH) –1.5 SDS; GH dose 0.19 mg/kg/week. Height gain was 1.1 SDS at a median age of 17.2 years. Growth response correlated positively with GH dose and weight at the start of GH treatment, and negatively with age and height SDS minus MPH SDS. The model explains 39% (error SD 1.2 cm) of the variability. Adult height correlated (R2 = 0.64) positively with height at GH start, MPH and the first-year responsiveness to GH, and negatively with age. Conclusions: Prepubertal children with ISS who show an appropriate first-year response to GH are likely to benefit from long-term treatment, even on low GH dosages.


Hormone Research in Paediatrics | 2007

Headache, Idiopathic Intracranial Hypertension and Slipped Capital Femoral Epiphysis during Growth Hormone Treatment: A Safety Update from the KIGS Database

Feyza Darendeliler; Georgios Karagiannis; Patrick Wilton

Background: Several uncommon adverse effects may be related to growth hormone (GH) treatment. Three potential side effects, headache, idiopathic intracranial hypertension (IIH) and slipped capital femoral epiphysis (SCFE), will be discussed. Data from 57,968 children in the KIGS (Pfizer International Growth Study database) were analyzed to determine the effects of recombinant human GH (Genotropin®) on these side effects. The diagnostic groups were idiopathic GH deficiency (IGHD) (n = 27,690), congenital GHD (CGHD) (n = 2,547), craniopharyngioma (n = 1,155), cranial tumours (n = 2,203), Turner syndrome (TS) (n = 6,092), idiopathic short stature (ISS) (n = 5,286), small for gestational age (SGA) (n = 2,973), chronic renal insufficiency (CRI) (n = 1,753) and Prader-Willi syndrome (PWS) (n = 1,368). Results: Total incidence (per 100,000 treatment years) of headache was 793.5 (n = 569). The incidence was significantly higher in the groups of patients with craniopharyngiomas, CGHD and cranial tumours than in the other diagnostic groups (p < 0.05 for all). IIH occurred in 41 children resulting in a total incidence (per 100,000 treatment years) of 27.7. The incidence (per 100,000 treatment years) was significantly lower in patients with IGHD (12.2) than in those with TS (56.4) (p = 0.0004), CGHD (54.5) (p = 0.0064), PWS (68.3) (p = 0.0263) and CRI (147.8) (p < 0.001). No cases of IIH were reported in the ISS group of patients. The median duration from onset of GH therapy to IIH ranged from 0.01 to 1.3 years in various diagnostic groups. SCFE was observed in a total of 52 children resulting in a total incidence (per 100,000 treatment years) of 73.4. The incidence (per 100,000 treatment years) was significantly lower in patients with IGHD (18.3) and in those children with ISS (14.5) than in the TS (84.5), cranial tumours (86.1) and craniopharyngioma groups (120.5) (p < 0.05 for all). No cases of SCFE were reported in the SGA and PWS groups. The median duration from onset of GH therapy to SCFE ranged from 0.4 to 2.5 years. Conclusions: The incidences of IIH and SCFE in this analysis are lower than the values reported in previous KIGS analyses and comparable to other databases. Patients with TS, organic GHD, PWS and CRI seem to be more prone to these side effects.


The Journal of Pediatrics | 2010

Growth Hormone Treatment in Children is not Associated with an Increase in the Incidence of Cancer: Experience from KIGS (Pfizer International Growth Database)

Patrick Wilton; Anders F. Mattsson; Feyza Darendeliler

OBJECTIVE To assess the incidence of cancer in patients treated with growth hormone (GH) in KIGS - the Pfizer International Growth Database-without cancer or any other condition in medical history known to increase the risk of cancer. STUDY DESIGN Data were analyzed from patients with growth disorders enrolled in an observational survey KIGS who had no known increased risk of developing cancer before starting recombinant human GH treatment. The incidence of cancer in this patient cohort (overall, site-specific, and according to etiology of growth disorder) was compared with the incidence in the general population by using the standardized incidence ratio (ie, relating the observed to expected number of cases with stratification for age, sex, and country). RESULTS A total of 32 new malignant neoplasms were reported in 58 603 patients, versus the 25.3 expected (incidence, 16.4 per 100 000 patient-years; standardized incidence ratio, 1.26; 95% confidence interval, 0.86-1.78). No category of growth disorder showed a statistically significant difference in observed compared with the expected number of cases. CONCLUSION There is no evidence in this series that GH treatment in young patients with growth disorders results in an increased risk of developing cancer relative to that expected in the normal population. However, surveillance for an extended time should continue to allow further assessment.


European Journal of Endocrinology | 2015

GH safety workshop position paper: a critical appraisal of recombinant human GH therapy in children and adults.

David B. Allen; Philippe F. Backeljauw; Martin Bidlingmaier; Beverly M. K. Biller; Margaret Cristina da Silva Boguszewski; Pia Burman; Gary Butler; Kazuo Chihara; Jens Sandahl Christiansen; Stefano Cianfarani; Peter Clayton; David R. Clemmons; Pinchas Cohen; Feyza Darendeliler; Cheri Deal; David Dunger; Eva Marie Erfurth; John S. Fuqua; Adda Grimberg; Morey W. Haymond; Claire Higham; Ken K. Y. Ho; Andrew R. Hoffman; Anita Hokken-Koelega; Gudmundur Johannsson; Anders Juul; John J. Kopchick; Peter A. Lee; Michael Pollak; Sally Radovick

Recombinant human GH (rhGH) has been in use for 30 years, and over that time its safety and efficacy in children and adults has been subject to considerable scrutiny. In 2001, a statement from the GH Research Society (GRS) concluded that ‘for approved indications, GH is safe’; however, the statement highlighted a number of areas for on-going surveillance of long-term safety, including cancer risk, impact on glucose homeostasis, and use of high dose pharmacological rhGH treatment. Over the intervening years, there have been a number of publications addressing the safety of rhGH with regard to mortality, cancer and cardiovascular risk, and the need for long-term surveillance of the increasing number of adults who were treated with rhGH in childhood. Against this backdrop of interest in safety, the European Society of Paediatric Endocrinology (ESPE), the GRS, and the Pediatric Endocrine Society (PES) convened a meeting to reappraise the safety of rhGH. The ouput of the meeting is a concise position statement.


Pediatrics | 2014

Changes Over Time in Sex Assignment for Disorders of Sex Development

Z. Kolesinska; S.F. Ahmed; Marek Niedziela; Jillian Bryce; M. Molinska-Glura; Martina Rodie; Jipu Jiang; Richard O. Sinnott; Ieuan A. Hughes; Feyza Darendeliler; Olaf Hiort; Y. van der Zwan; Martine Cools; Tulay Guran; P.-M. Holterhus; Silvano Bertelloni; Lidka Lisa; Wiebke Arlt; Nils Krone; Mona Ellaithi; Antonio Balsamo; I. Mazen; Anna Nordenström; K. Lachlan; Mona Alkhawari; P. Chatelain; N. Weintrob

BACKGROUND AND OBJECTIVE: It is unclear whether the proportion of infants with a disorder of sex development who are raised as male or female has changed over time. The temporal trends in sex assignment of affected cases entered in the International Disorder of Sex Development (I-DSD) Registry were studied. METHODS: Cases of disorders of sex development reported as partial androgen insensitivity syndrome (PAIS; n = 118), disorder of gonadal development (DGD; n = 232), and disorder of androgen synthesis (DAS; n = 104) were divided into those who were born before 1990, 1990–1999, and after 1999. External appearance of the genitalia was described by the external masculinization score. RESULTS: The median (5th–95th percentile) external masculinization scores of those infants with PAIS, DGD, and DAS who were raised as boys were 6 (2–9), 6 (3–9), and 6 (1–12), respectively, and were significantly higher than in those raised as girls (2 [0–6], 2 [0–7], and 0 [0–5], respectively); this difference was maintained in the 3 temporal birth cohorts (P < .01). Of the 118 cases in the pre-1990 cohort, 41 (35%) were raised as boys; of the 148 cases in the 1990–1999 cohort, 60 (41%) were raised as boys; and of the 188 cases in the post-1999 cohort, 128 (68%) were raised as boys. CONCLUSIONS: Although there is an association between the external appearance of the genitalia and the choice of sex assignment, there are clear temporal trends in this practice pointing toward an increased likelihood of affected infants being raised as boys. The impact of this change in practice on long-term health outcomes requires additional focus.


Acta Paediatrica | 2006

Recurrence of brain tumours in patients treated with growth hormone: Analysis of KIGS (Pfizer International Growth Database)

Feyza Darendeliler; Georgios Karagiannis; Patrick Wilton; Michael B. Ranke; Kerstin Albertsson-Wikland; David A. Price

Background: Growth hormone (GH) has been used successfully in the treatment of short stature secondary to GH deficiency in survivors of childhood brain tumours. There has been concern that GH might increase the risk of recurrence. Aim: To analyse KIGS (Pfizer International Growth Database) with respect to tumour recurrence in patients with brain tumours. Methods: Data for tumour recurrence were analysed retrospectively in 1038 patients with craniopharyngiomas, 655 with medulloblastomas, 113 with ependymomas, 297 with germinomas, and 400 with astrocytomas or gliomas. All patients had received recombinant human GH (Genotropin®, Pfizer Inc.). Results: Recurrence‐free survival rates were 63% at a follow‐up of 10.3 y in craniopharyngioma, 69% in 9.1 y in the glial tumours, 71% in 7.4 y in germinomas, 92% in 4.6 y in medulloblastomas and 89% in 2.5 y in ependymomas. Dose of GH and treatment modalities did not differ significantly between patients with and without recurrence.


Pediatric Research | 2007

Major determinants of height development in Turner syndrome (TS) patients treated with GH: Analysis of 987 patients from KIGS.

Michael B. Ranke; Anders Lindberg; Angel Ferrández Longás; Feyza Darendeliler; Kerstin Albertsson-Wikland; David B. Dunger; Wayne S. Cutfield; Maithe Tauber; Patrick Wilton; Hartmut A. Wollmann; Edward O. Reiter

Little is known about factors determining height outcome during GH treatment in Turner syndrome (TS). We investigated 987 TS children within the Kabi International Growth Study (KIGS) who had reached near adult height (NAH) after >4 y GH treatment (including >1 y before puberty). Through multiple regression analysis we developed a model for NAH and total gain. Our results were as follows (median): 1) At start, age 9.7 yrs, height (HT) 118.0 cm (0.0 TS SDS), projected adult height 146.1 cm, GH dose 0.27 mg/kg wk; 2) NAH HT 151.0 cm (1.5 TS SDS); 3) Prepubertal gain 21.2 cm (1.6 TS SDS); 4) Pubertal gain 9.4 cm (0.0 TS SDS). NAH correlated (r2 = 0.67) with (ranked) HT at GH start (+), 1st year responsiveness to GH (+), MPH (+), age at puberty onset (+), age at GH start (−), and dose (+). The same factors explained (R2 = 0.90) the total HT gain. However, HT at GH start correlated negatively. Karyotype had no influence on outcome. Evidently, height at GH start (the taller, the better), age at GH start (the younger, the better), the responsiveness to GH (the higher, the better) and age at puberty (the later, the better) determine NAH.


The Journal of Clinical Endocrinology and Metabolism | 2014

Novel associations in disorders of sex development: Findings from the I-DSD registry

Kathryn Cox; Jillian Bryce; Jipu Jiang; Martina Rodie; Richard O. Sinnott; Mona Alkhawari; Wiebke Arlt; Laura Audí; Antonio Balsamo; Silvano Bertelloni; Martine Cools; Feyza Darendeliler; Stenvert L. S. Drop; Mona Ellaithi; Tulay Guran; Olaf Hiort; Paul-Martin Holterhus; Ieuan A. Hughes; Nils Krone; Lidka Lisa; Yves Morel; Olle Söder; Peter Wieacker; S. Faisal Ahmed

Context: The focus of care in disorders of sex development (DSD) is often directed to issues related to sex and gender development. In addition, the molecular etiology remains unclear in the majority of cases. Objective: To report the range of associated conditions identified in the international DSD (I-DSD) Registry. Design, Setting, and Patients: Anonymized data were extracted from the I-DSD Registry for diagnosis, karyotype, sex of rearing, genetic investigations, and associated anomalies. If necessary, clarification was sought from the reporting clinician. Results: Of 649 accessible cases, associated conditions occurred in 168 (26%); 103 (61%) cases had one condition, 31 (18%) had two conditions, 20 (12%) had three conditions, and 14 (8%) had four or more conditions. Karyotypes with most frequently reported associations included 45,X with 6 of 8 affected cases (75%), 45,X/46,XY with 19 of 42 cases (45%), 46,XY with 112 of 460 cases (24%), and 46,XX with 27 of 121 cases (22%). In the 112 cases of 46,XY DSD, the commonest conditions included small for gestational age in 26 (23%), cardiac anomalies in 22 (20%), and central nervous system disorders in 22 (20%), whereas in the 27 cases of 46,XX DSD, skeletal and renal anomalies were commonest at 12 (44%) and 8 (30%), respectively. Of 170 cases of suspected androgen insensitivity syndrome, 19 (11%) had reported anomalies and 9 of these had confirmed androgen receptor mutations. Conclusions: Over a quarter of the cases in the I-DSD Registry have an additional condition. These associations can direct investigators toward novel genetic etiology and also highlight the need for more holistic care of the affected person.


Current Opinion in Endocrinology, Diabetes and Obesity | 2014

Metabolic syndrome in young people.

Sukran Poyrazoglu; Firdevs Bas; Feyza Darendeliler

Purpose of reviewThe prevalence of obesity is on the increase, and consequently metabolic syndrome is also becoming a serious health problem in children and adolescents all over the world. This review attempts to summarize the recent literature on metabolic syndrome in children and adolescents. Recent findingsTo date, a standard definition of metabolic syndrome for the pediatric population is not available. Recently, the International Diabetes Federation has proposed a new set of criteria to define metabolic syndrome in children and adolescents aged 6–16 years. The relationships between obesity, insulin resistance and metabolic syndrome may be explained by the pattern of lipid partitioning. Fatty liver plays a central role in the insulin-resistant state in obese adolescents. Although insulin resistance has been proposed as the central factor leading to the abnormalities observed in metabolic syndrome, most definitions of metabolic syndrome use impaired fasting glucose as a marker. Nutrition impairment during both prenatal and early postnatal life can cause metabolic disturbances leading to insulin-resistance, type 2 diabetes, hypertension and cardiovascular disease. SummaryMetabolic syndrome prevalence in children and adolescents is on the increase. Therefore, the emphasis in all studies and programs related to metabolic syndrome should be focused on prevention, early detection of metabolic risk factors and interventions that will have a significant impact on future adult health.

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