Hülya Günöz

Body mass index references for Turkish children

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.

Frequency of renal malformations in Turner syndrome: analysis of 82 Turkish children

Abstract We evaluated the frequency of renal malformations in relation to nonmosaic 45,X (group A, 45 patients, 54.9%) and mosaic/structural abnormalities of X (group B, 37 patients, 45.1%) in 82 Turkish patients with Turner syndrome (TS). Ultrasonography of the kidneys and collecting system was performed in all patients. Of the 82 patients, 31 had different renal malformations (37.8%). Horse-shoe kidney was observed in 9 (29.0%) of the 31 patients, and 17 patients (54.8%) had various collecting system malformations, while 5 (16.2%) had malrotation and other positional abnormalities. The prevalence of renal malformations was significantly higher in group A (51.1%) than group B (21.6%) (2:7.94, P<0.05). Although 8 of the 9 patients with horse-shoe kidney had the 45,X karyotype, collecting system malformations were observed more frequently in group B. Recurrent urinary tract infections (UTIs) were detected during follow-up in 7 patients, and hypertension developed in 3 patients. In patients who had a normal baseline nephrological evaluation, no problem suggesting renal disease developed during follow-up. We conclude that all forms of TS should have routine nephrological screening on diagnosis, since structural malformations of the kidney occur more frequently in nonmosaic 45,X TS, while collecting system malformations are mostly seen in mosaic/structural X forms. Those included in the group for nephrological follow-up had an increased risk for hypertension and/or UTI.

Successful Therapy with Calcium Channel Blocker (Nifedipine) in Persistent Neonatal Hyperinsulinemic Hypoglycemia of Infancy

The appropriate management of persistent hyperinsulinemic hypoglycemia of infancy (PHHI) still remains controversial. Some patients show a response to treatment with diazoxide or somatostatin, but a number of children require total or near-total pancreatectomy to control hyperinsulinism. Recent studies suggest a dysfunction in the adenosine triphosphate-sensitive potassium channel present in the plasma membrane of pancreatic beta-cells in PHHI. The closure of these channels initiating the depolarization of the beta-cell membrane and opening of calcium channels results in an increase in intracellular calcium which triggers insulin secretion. A calcium channel blocking agent has been shown to block this process and decrease insulin secretion of the nesidioblastotic beta-cells in vitro and to control the hyperinsulinemic hypoglycemia of the patient in vivo. To examine the efficacy of calcium channel blocker therapy, three patients with PHHI were treated with nifedipine. PHHI was diagnosed by inappropriately high insulin levels for low blood glucose levels at 8-10 days of age. Normoglycemia was maintained by a high dose of glucose infusion at a rate of 14-16 mg/kg/min. Therapy using diazoxide and/or somatostatin analogue failed to restore euglycemia in these three patients. The first patient underwent near-total pancreatectomy; however, hyperinsulinism recurred 30 days after surgery. All patients were started on short acting nifedipine at a dose of 0.3 mg/kg/day per os in four doses. To maintain blood glucose levels in normal ranges, the dose of nifedipine was progressively increased to 0.7-0.8 mg/kg/day. Glucose infusion rate to restore euglycemia decreased and was discontinued on the 4th to 10th day of nifedipine treatment. The patients, who have now been followed on nifedipine therapy for over 12 months, are normoglycemic with normal insulin levels. The growth and neuromotor development of the patients are unremarkable except for mild developmental delay of the patient who underwent near-total pancreatectomy. No side effects were encountered at the doses used. In conclusion, calcium channel blocking agents can be used with efficacy and safety in PHHI to control the hyperinsulinemia.

Constitutional Delay of Growth and Puberty: From Presentation to Final Height

This retrospective study evaluated clinical characteristics of patients with constitutional delay of growth and puberty (CDGP) at presentation, during puberty and at final height. The records of 151 children (105 boys, 46 girls) with CDGP were reviewed and the results were evaluated with respect to findings in healthy Turkish schoolchildren. CDGP was twice as frequent in boys as in girls. Height and weight deficit and short sitting height of the children were evident at presentation and continued up to final height. Mean age of onset of puberty was retarded by 2.5 years in girls and by 3 years in boys. The time between onset of puberty and pubertal growth spurt was shorter in both girls and boys than in the controls. Peak growth velocity was compromised in both girls and boys. Forty-one patients (30 boys, 11 girls) reached final height (FH). Mean FH was shorter than both target height and predicted adult height. The Bayley-Pinneau method was found to be a better predictor of FH than either the Tanner-Whitehouse method or target height. FH also showed correlation with the fathers height. There was no effect of testosterone treatment on final height. Height deficit at onset of puberty, shorter duration between onset of puberty and pubertal growth spurt, compromised peak growth velocity and short upper segment due to delayed puberty, are findings which may explain the decreased final height of children with CDGP.

Procedure for Neonatal Screening for Congenital Adrenal Hyperplasia due to 21-Hydroxylase Deficiency

The value of screening of neonates for congenital adrenal hyperplasia is not universally accepted. Procedures for screening are recommended here in order to provide a structure to the testing and ultimately bring together data that will allow the effect of screening to be judged for benefit or dismissed as no better than clinical recognition of the disease state.

A Novel X-linked Disorder with Developmental Delay and Autistic Features

Genomic duplications that lead to autism and other human diseases are interesting pathological lesions since the underlying mechanism almost certainly involves dosage sensitive genes. We aim to understand a novel genomic disorder with profound phenotypic consequences, most notably global developmental delay, autism, psychosis, and anorexia nervosa.

Reference Values for Weight, Height, Head Circumference, and Body Mass Index in Turkish Children.

Objective: This study aimed to integrate the existing updated reference standards for the growth of Turkish infants and children and to compare these values with World Health Organization (WHO) reference data, data from some European countries, and also with previous local data. Weight, height, and head circumference measurements were obtained on 2,391 boys and 2,102 girls who were regular attenders of a well child clinic and on 1,100 boys and 1,020 girls attending schools in relatively well-off districts in İstanbul. Mean number of measurements per child was 8.2±3.6 in the age group 0-5 years and 5.5±3.3 in the age group 6-18 years. All children were from well-to-do families and all were healthy. All measurements with the exception of measurements at birth, which were based on reported values, were done by trained personnel. Methods: The LMS method was used in the analyses and in the construction of the percentile charts. There is an increase in weight for age and body mass index values for age starting in prepubertal ages, indicating an increasing trend for obesity. Results: Compared to WHO reference data, weight and height values in Turkish children were slightly higher in infants and in children younger than 5 years, while they showed similarity to those reported for children from Norway and Belgium. Head circumference values, which were slightly higher than the WHO references in the first 5 years, were comparable to the data on Belgian and Norwegian children in the first 9 years of life. At older ages, Turkish children showed higher values for head circumference. Conclusion: The relatively larger head circumference values were interpreted to reflect a genetic characteristic.

HLA-DR and -DQ associations with insulin-dependent diabetes mellitus in a population of Turkey

Genetic susceptibility to insulin-dependent diabetes mellitus (IDDM) has been shown to be associated with MHC in many studies. To extend this data with a population with relatively low IDDM incidence, MHC DRB, DQA, and DQB have been investigated by polymerase chain reaction and sequence specific oligonucleotide probe hybridization (PCR/SSO) in 178 IDDM patients from Turkey and compared to 248 healthy controls. Significant differences are detected between IDDM and control groups in the frequencies of DRB1*0402 DQA1*03 DQB1*0302 (28.1% vs. 5.2%, p < 0.0001, OR: 7.1) and DRB1*0301 DQA1*0501 DQB1*02 (57% vs. 18.1%, p < 0.0001, OR: 6.1). Among the negative associations, the most strong ones are with DRB1*1401 DQA1*0101 DQB1*0503 (0.6% vs. 8.9%, p < 0.0001, OR: 0.1), DRB1*1502 DQA1*0103 DQB1*0601 (1.1% vs. 7.7%, p = 0.0023, OR: 0.1), DRB1*1301 DQA1*0103 DQB1*0603 (0.6% vs. 6.9%, p = 0.0039, OR: 0.2) and DRB1*1101 DQA1*0501 DQB1*0301 (3.9% vs. 12.1%, p < 0.0001, OR: 0.2). When the DRB, DQA or DQB genotypes of the susceptible alleles are compared, the most strong susceptibility marker of the disease is found to be DRB1*0301/*04 (31.4% vs. 2.8%, p < 0.0001, OR: 15.8) and among these, heterozygote genotype DRB1*0301/*0401 (4.5% vs. 0, p = 0.0008, OR: 24.8). These results confirm the positive associations with IDDM previously observed in other Caucasian populations and reveal many negative and strong associations which maybe underlining several characteristics that distinguish Turkish diabetics form other Caucasians.

Successful Results of Pamidronate Treatment in Children With Osteogenesis Imperfecta With Emphasis on the Interpretation of Bone Mineral Density for Local Standards

Aim: To assess the long-term effect of pamidronate therapy on bone mineral metabolism and bone mineral density (BMD) in children with osteogenesis imperfecta (OI) and to evaluate BMD results with respect to national standards. Methods: Pamidronate was administered intravenously on 3 consecutive days every 3 to 4 months at a dose of 1 mg/kg/d in 35 patients. Infusion cycles ranged from 4 to 17. Serum calcium, phosphorus, bone turnover markers, L1-L4 areal BMD (aBMD), and fracture rate were evaluated. Areal BMD Z scores were compared with national sex-specific reference data and volumetric BMD Z scores. Results: In all children, linear growth continued along the same percentile during treatment. All parameters of bone turnover showed a decrease. L1 to L4 aBMD and Z score increased markedly, and fracture rate decreased in all patients during therapy. The mean annual percent gain in aBMD was highest in the first year and slowed down in subsequent years. Mean L1 to L4 aBMD Z scores according to Turkish reference data were higher than that of manufacturer values (P = 0.004). Correction of L1 to L4 vertebrae for bone size yielded to a decrease in osteoporosis in OI patients (41.5% vs 22.3%). Conclusions: Bone mineral density increased and fracture rate decreased in children and infants with OI during pamidronate treatment. Prevalence of osteoporosis decreased after correction for national standard and volumetric BMD. Use of an appropriate reference database and method of data analysis are very important for correct evaluation of osteoporosis.

Self‐efficacy and its interrelation with family environment and metabolic control in Turkish adolescents with type 1 diabetes

To explore the relationship between self‐efficacy, family environment (cohesion and organization) and metabolic control.