Yazar "Ozbek, Mehmet Nuri" seçeneğine göre listele

Listeleniyor 1 - 6 / 6
  • [ X ]
    Öğe
    Clinical characteristics and phenotype-genotype analysis in Turkish patients with congenital hyperinsulinism; predominance of recessive KATP channel mutations
    (Bioscientifica Ltd, 2014) Demirbilek, Huseyin; Arya, Ved Bhushan; Ozbek, Mehmet Nuri; Akinci, Aysehan; Dogan, Murat; Demirel, Fatma; Houghton, Jayne
    Objective: Congenital hyperinsulinism (CHI) is the commonest cause of hyperinsulinaemic hypoglycaemia in the neonatal, infancy and childhood periods. Its clinical presentation, histology and underlying molecular biology are extremely heterogeneous. The aim of this study was to describe the clinical characteristics, analyse the genotype phenotype correlations and describe the treatment outcome of Turkish CHI patients. Design and methods: A total of 35 patients with CHI were retrospectively recruited from four large paediatric endocrine centres in Turkey. Detailed clinical, biochemical and genotype information was collected. Results: Diazoxide unresponsiveness was observed in nearly half of the patients (n= 17; 48.5%). Among diazoxide-unresponsive patients, mutations in ABCC8/KCNJ11 were identified in 16 (94%) patients. Among diazoxide-responsive patients (n=18), mutations were identified in two patients (11%). Genotype phenotype correlation revealed that mutations in ABCC8/KCNJ11 were associated with an increased birth weight and early age of presentation. Five patients had p.L1171fs (c.3512de1) ABCC8 mutations, suggestive of a founder effect. The rate of detection of a pathogenic mutation was higher in consanguineous families compared with non-consanguineous families (87.5 vs 21%; P<0.0001). Among the diazoxide-unresponsive group, ten patients were medically managed with octreotide therapy and carbohydraterich feeds and six patients underwent subtotal pancreatectomy. There was a high incidence of developmental delay and cerebral palsy among diazoxide-unresponsive patients. Conclusions: This is the largest study to report genotype phenotype correlations among Turkish patients with CHI. Mutations in ABCC8 and KCNJ11 are the commonest causes of CHI in Turkish patients (48.6%). There is a higher likelihood of genetic diagnosis in patients with early age of presentation, higher birth weight and from consanguineous pedigrees.
  • [ X ]
    Öğe
    Clinical features of generalized lipodystrophy in Turkey: A cohort analysis
    (Wiley, 2023) Yildirim Simsir, Ilgin; Tuysuz, Beyhan; Ozbek, Mehmet Nuri; Tanrikulu, Seher; Celik Guler, Merve; Karhan, Asuman Nur; Denkboy Ongen, Yasemin
    Aim: To describe the Turkish generalized lipodystrophy (GL) cohort with the frequency of each complication and the death rate during the period of the follow-up. Methods: This study reports on 72 patients with GL (47 families) registered at different centres in Turkey that cover all regions of the country. The mean +/- SD follow-up was 86 +/- 78 months. Results: The Kaplan-Meier estimate of the median time to diagnosis of diabetes and/or prediabetes was 16 years. Hyperglycaemia was not controlled in 37 of 45 patients (82.2%) with diabetes. Hypertriglyceridaemia developed in 65 patients (90.3%). The Kaplan-Meier estimate of the median time to diagnosis of hypertriglyceridaemia was 14 years. Hypertriglyceridaemia was severe (>= 500 mg/dl) in 38 patients (52.8%). Seven (9.7%) patients suffered from pancreatitis. The Kaplan-Meier estimate of the median time to diagnosis of hepatic steatosis was 15 years. Liver disease progressed to cirrhosis in nine patients (12.5%). Liver disease was more severe in congenital lipodystrophy type 2 (CGL2). Proteinuric chronic kidney disease (CKD) developed in 32 patients (44.4%) and cardiac disease in 23 patients (31.9%). Kaplan-Meier estimates of the median time to diagnosis of CKD and cardiac disease were 25 and 45 years, respectively. Females appeared to have a more severe metabolic disease, with an earlier onset of metabolic abnormalities. Ten patients died during the follow-up period. Causes of death were end-stage renal disease, sepsis (because of recurrent intestinal perforations, coronavirus disease, diabetic foot infection and following coronary artery bypass graft surgery), myocardial infarction, heart failure because of dilated cardiomyopathy, stroke, liver complications and angiosarcoma. Conclusions: Standard treatment approaches have only a limited impact and do not prevent the development of severe metabolic abnormalities and early onset of organ complications in GL.
  • [ X ]
    Öğe
    Genotype, phenotype characteristics and long-term follow-up of patients with Vitamin D Dependent Rickets Type IA (VDDR1a): A nationwide multicentre retrospective cross-sectional study
    (Karger, 2022) Cayir, Atilla; Demirbilek, Huseyin; Turkyilmaz, Ayberk; Turan, Serap; Bereket, Abdullah; Darendeliler, Feyza; Ozbek, Mehmet Nuri
    [Abstract Not Available]
  • [ X ]
    Öğe
    Metreleptin Treatment in a Boy with Congenital Generalized Lipodystrophy due to Homozygous c.465_468delGACT (p.T156Rfs*8) Mutation in the BSCL2 Gene: Results From the First-year
    (Galenos Publ House, 2023) Ozalkak, Servan; Demiral, Meliha; Unal, Edip; Tas, Funda Feryal; Onay, Huseyin; Demirbilek, Huseyin; Ozbek, Mehmet Nuri
    Congenital generalized lipodystrophy (CGL) is a rare, autosomal recessive disorder characterized by an almost complete absence of body fat. In CGL, patients may have hyperphagia due to leptin deficiency. Recombinant human leptin (metreleptin) has been suggested as an effective treatment option. We present successful treatment with metreleptin in a boy with CGL and results from the first year of follow-up. An eight-month-old boy presented with excessive hair growth and a muscular appearance. On examination he had hypertrichosis, decreased subcutaneous adipose tissue over the whole body and hepatomegaly. Laboratory investigations revealed hypertriglyceridemia, hyperinsulinemia, elevated liver transaminases and low leptin levels. Molecular genetic analysis detected a homozygous, c.465_468delGACT (p.T156Rfs*8) mutation in the BSCL2 gene. A diagnosis of CGL type 2 was considered. Despite dietary intervention, exercise, and treatment with additional omega-3 and metformin, the hypertriglyceridemia, hyperinsulinemia, and elevated liver transaminase levels worsened. Metreleptin treatment was started and after one year hyperphagia had disappeared, and there was dramatic improvement in levels of insulin, hemoglobin A1c, triglycerides and liver transaminases. Hepatosteatosis was lessened and hepatosplenomegaly was much improved. Metreleptin appears to be an effective treatment option in children with CGL that remarkably improved metabolic complications in the presented case. Initiation of metreleptin treatment in the early period may decrease mortality and morbidity, and increase the quality of life in children with CGL.
  • [ X ]
    Öğe
    Nutritional megaloblastic anemia in young Turkish children is associated with vitamin B-12 deficiency and psychomotor retardation
    (Lippincott Williams & Wilkins, 2006) Katar, Selahattin; Ozbek, Mehmet Nuri; Yaramis, Ahmet; Ecer, Sultan
    We aimed to investigate the presence of psychomotor retardation, physical and laboratory examination in infants with megaloblastic anemia. Inclusion criteria for the study were; age 9 to 36 months, refusal of food except for breast and cow milk, loss of appetite, developmental delay, significant pallor, and hypersegmentation neutrophils in the peripheral blood smear. A total of 33 children fulfilling the inclusion criteria were enrolled among 3368 patients attending Pediatric Outpatient Clinics of Sirnak-Cizre State Hospital between January 25, 2004 and May 5, 2004. Mean age was 16.4 months. Thirty-two patients had Vitamin B(12) deficiency, 1 patient had folate deficiency, and 10 patients had combined vitamin B(12) and folate deficiency. Statistically, a positive significant relationship was detected between serum vitamin B(12) levels and mean corpuscular volume (P = 0.001, r = 0.56), and between vitamin B(12) levels and hemoglobin (P = 0.004, r = 0.49). We believe that preventative measures such as fortification of flour with vitamin B(12), nutritional support with vitamin B(12) for the mother during pregnancy and nursing, provision of adequate primary preventive health services, and starting complementary food after 6 months of age are important determinants for preventing megaloblastic anemia.
  • [ X ]
    Öğe
    Prepubertal Unilateral Gynecomastia: Report of 2 Cases
    (Galenos Yayincilik, 2014) Demirbilek, Huseyin; Bacak, Gokhan; Baran, Riza Taner; Avci, Yahya; Baran, Ahmet; Keles, Aysenur; Ozbek, Mehmet Nuri
    Prepubertal unilateral gynecomastia is an extremely rare condition. At present, its etiology and management strategy are not well known. Two unrelated prepubertal boys of ages 8 and 9 who presented with complaints of unilateral enlargement of breast tissue are reported. Physical examination, biochemical, hormonal and oncologic work-up findings were normal. Both patients were treated with peripheral liposuction successfully. Histopathological and immunohistochemical examinations showed benign fibroglandular gynecomastia and intensive (3+) estrogen receptor expression in 100% of periductal epithelial cells. Although an extremely rare and generally benign condition, patients with prepubertal unilateral gynecomastia should have a full endocrine and oncologic work-up.