Kutluhan Yilmaz

Central corneal thickness is lower in osteogenesis imperfecta and negatively correlates with the presence of blue sclera

Background:  Osteogenesis imperfecta (OI) is a rare, autosomal‐inherited, connective tissue disorder characterised by bone fractures, deafness and blue sclera. Additional ocular findings are decreased ocular rigidity, myopia, glaucoma, keratoconus, corneal opacity, small corneal diameter and congenital Bowmans layer agenesis.

Bone mineral density in children with neurofibromatosis 1

Aim: Our aim was to detect the status of bone mineral density (BMD) in children with NF1, and thus to help the management of the skeletal complications of NF1.

Evaluation of laboratory tests in dehydrated children with acute gastroenteritis

Objective:  The aim of the present study was to demonstrate the utility of laboratory tests in predicting dehydration severity.

Prevalence and correlates of restless legs syndrome in adolescents

Aim  The aim of this study was to determine the prevalence and correlates of restless legs syndrome (RLS) in adolescents.

Riboflavin treatment in a case with l-2-hydroxyglutaric aciduria

L-2-hydroxyglutaric aciduria (LHGuria) is a rare neurometabolic disorder, which has characteristic clinical and laboratory features. The recent findings imply that LHG dehydrogenase is responsible for the disease and is FAD-dependent. Therefore, it might be expected that riboflavin could enhance any residual activity. We present our observations from nearly 2-year-long riboflavin treatment in a 16-year-old boy with LHGuria. During riboflavin treatment of 100 mg/d, partial improvement in his cognitive and motor performances was observed. Urinary LHG excretion decreased from 5990 mmol/mol creatinine to 1490 mmol/mol creatinine. Moreover, when riboflavin treatment was interrupted, significant disturbances in both symptoms and urinary LHG excretion (6360 mmol/mol creatinine) occurred in the patient. After the resettlement of riboflavine treatment, the patient resumed to his previous clinical status in a week. The improvement went further minimally under the dose of 200mg/d, but no further improvement happened with 300 mg/d. The present case suggests that riboflavin could be considered as a potential therapeutic approach in LHGuria until the optimal treatment of LHGuria is established.

Decreased central corneal thickness in children with Down syndrome.

PURPOSE A cross-sectional, masked, case-control study was undertaken to investigate whether central corneal thickness is affected in children with Down syndrome and to focus on its clinical significance. PARTICIPANTS AND METHODS Twenty-eight children with Down syndrome (15 boys and 13 girls) aged 5 to 15 years and 20 age-matched and gender-matched healthy control subjects (11 boys and 9 girls) from a similar ethnic background were enrolled in the study. Central corneal thickness was measured by ultrasound pachymetry. Only the right eye of each child in each group was included in the statistical analysis. The Mann-Whitney U test was used and a P value of less than .05 was considered significant. RESULTS The mean ages of the children with Down syndrome (9.28 +/- 3.47 years) and the healthy control subjects (8.75 +/- 3.30 years) were comparable (P > .05). Central corneal thickness values were below 500 microm in 19 (67.8%) of the 28 children with Down syndrome, 4 of which were less than 450 microm. However, all central corneal thickness measurements in the control eyes were more than 500 microm. The mean central corneal thickness in the children with Down syndrome was significantly (P < .001) less (488.39 +/- 39.87 microm) than that in the healthy control subjects (536.25 +/- 20.70 microm). Mean keratometric values were significantly (P < .001) higher in the eyes of the children with Down syndrome (46.35 +/- 1.28 D) than in the eyes of the control subjects (43.32 +/- 1.15 D). CONCLUSIONS Children with Down syndrome had a decreased central corneal thickness compared with healthy control subjects. Decreased central corneal thickness may give an artificially low intraocular pressure measurement by applanation tonometry. Central corneal thickness must be considered when developing approaches for keratorefractive treatment of patients with Down syndrome.

Urotensin-II Immunoreactivity in Children with Chronic Glomerulonephritis

Background. Human urotensin-II (hU-II) is one of the most potent vasoconstrictors in mammals. To our knowledge, there is no study about the role of U-II in childhood glomerulonephritis.We first determined the expression of h U‐II in kidneys of children with chronic glomerular diseases. Methods. Normal human kidneys were obtained from postmortem biopsies and compared with the kidney biopsy specimens of 24 children with membranoproliferative glomerulonephritis (MPGN) and 6 children with membranous GN. Kidney needle biopsies in 10% neutral buffered-formalin prior to routine processing through to embedded blocking sections were cut, and immunohistochemical reactions were performed on parafin-embedded tissue by an avidin-biotin peroxidase complex method. The antibodies used in the present study were hU-II. The positivities were revealed as weak (+), moderate (++), and severe (+++), according to the color intensity. Results. In kidneys of children with MPGN, differently fom the normal kidneys, more dense U-II immunoreactivity was seen in the glomerular basement membrane (GBM), glomerular mesangium, Bowman capsule, and tubules. Interestingly, we also observed U-II immunoreactivity in crescents. In children with MGN, U-II was mostly seen in GBM and Bowman capsule. Conclusion. Our findings suggest that U-II may have a possible autocrine/paracrine function in the kidneys, and may be an important target molecule in studying renal pathophsiology.

Alendronate treatment in osteogenesis imperfecta.

Aims:Osteogenesis imperfecta (OI) is a chronic, disabling condition characterized by bone fragility resulting from defective production of type I collagen. Pamidronate therapy is the most extensively studied treatment and has proved beneficial. Our objective was to evaluate the effect of alendronate, a more potent bisphosphonate than pamidronate, in OI. Materials and Methods:Three patients (age, 3–7 years; mean, 5 years) (one case, type III; 2 cases, type IV) have been given alendronate (0.3–0.56 mg/kg per day orally) for 2 years. Number of fractures, ambulation, height growth, and bone mineral density by dual-energy x-ray absorptiometry (DXA) were followed up. Results:Bone mineral density improved significantly after the 2-year alendronate treatment, which increased by 47.8% to 106.6% in the lumbar spine and by 24% to 51.4% in forearm bones. The z-score of lumbar spine DXA values increased from −5.26 ± 0.84 to −3.1 ± 0.59. The mean of fracture rates did not change significantly. Only one of the patients was highly limited in ambulation. She had curved legs and could not sit without support before the treatment. She improved to walk with help by the treatment. Serum parathormone and alkaline phosphatase concentrations did not change significantly. No side effect was detected in clinical and laboratory evaluations. Conclusion:The study suggests that alendronate is a safe and well-tolerated drug and that it could increase bone density in children with OI, all of which encourage further studies with the bisphosphonates that are more potent than pamidronate and can be used orally. In addition, this study is the first report using the forearm bone mineral density measurement in OI.

Epidemiological study of self-reported sleep problems in Turkish high school adolescents

The aim of the present study was to investigate the frequency and correlates of a variety of sleep problems in adolescents.

A correlative study of FDG PET, MRI/CT, electroencephalography, and clinical features in subacute sclerosing panencephalitis.

Objective: To describe F-18 fluorodeoxyglucose positron emission tomography (FDG PET) profile in patients with subacute sclerosing panencephalitis (SSPE) and to investigate its possible correlation with clinical, electroencephalography (EEG) or magnetic resonance imaging/computed tomography (MRI/CT) findings. Methods: EEG recording, MRI/CT and FDG PET imaging were performed in 16 patients with SSPE (1.9–15.6 years). FDG PET scans were assessed visually and in standardized uptake values. Finally, all the findings including clinical data were compared. Results: MRI was abnormal in 10 patients. It was normal in 6 of 10 patients in earlier clinical stages. Nonspecific T2-weighted white matter findings were the most consistent MRI finding (10 patients). No thalamic lesion was detected in MRI/CT. FDG PET imaging was abnormal in 14 patients (8/10 patients in earlier stages). Glucose metabolism was decreased in thalamus, cerebellum or cerebral cortex in 12, 12, and 9 patients, respectively. Frontal cortex metabolism was preserved in earlier clinical stages. FDG PET imaging revealed putaminal hypermetabolism in 7 patients. However, MRI indicated striatal abnormality only in 2 patients with prolonged disease and later clinical stage. Three patients with putaminal hypermetabolism experienced a more rapid clinical deterioration. Onset age of SSPE, age of measles infection and EEG findings were not correlated with the imaging findings. Conclusions: Our findings suggest that FDG PET imaging can indicate affected brain regions in SSPE more confidently and earlier than MRI. FDG PET imaging would provide new insights into the pathogenesis of SSPE and help to develop new approaches to the patients with SSPE.