Aytül Noyan
Başkent University
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Featured researches published by Aytül Noyan.
Clinical Nephrology | 2004
Bayazit Ak; Aytül Noyan; Cengiz N; Ali Anarat
AIM The aim of the present study is to report our clinical experiences with MMF in problematic children with chronic glomerulonephritis resistant to corticosteroids and/or other immunosuppressive drugs. PATIENTS AND METHODS Ten patients with chronic glomerulonephritis resistant to treatment with corticosteroids and other immunosuppressive drugs were treated with mycophenolate mofetil (MMF). Causes of chronic glomerulonephritis were mesangial proliferative glomerulonephritis (4), membranoproliferative glomerulonephritis (3), chronic sclerosing glomerulonephritis (1), focal segmental glomerulosclerosis (1), diffuse endo- and extracapillary proliferative glomerulonephritis (1). MMF 15 mg/kg was used in combination with low-dose corticosteroids and angiotensin-converting enzyme inhibitors. RESULTS During 24 weeks of MMF therapy, no significant changes were detected in mean serum creatinine, albumin and proteinuria. Severe leukopenia was seen in 1 patient. Additional adverse effects, including nausea and diarrhea, were observed in another patient when the dosage was increased to 20 mg/kg per day. During MMF treatment proteinuria decreased slightly without remission in 6 of 10 patients. CONCLUSION Further data and clinical trials are needed to evaluate the possible role of MMF in the treatment of chronic glomerulonephritis of similar etiologies in pediatric patients.
Transplantation | 2016
Britta Höcker; Sebastian Zencke; Kai Krupka; Alexander Fichtner; Lars Pape; Luca Dello Strologo; Isabella Guzzo; Rezan Topaloglu; Birgitta Kranz; Jens König; Martin Bald; Nicholas J.A. Webb; Aytül Noyan; Hasan Dursun; Stephen D. Marks; Fatoş Yalçınkaya; Florian Thiel; Heiko Billing; Martin Pohl; Henry Fehrenbach; Thomas Bruckner; Burkhard Tönshoff
Background Cytomegalovirus (CMV) replication and disease, with its associated morbidity and poor transplant outcome, represents a serious threat to transplant recipients. The pediatric kidney transplant population is at a particularly increased risk of CMV infection. Methods We therefore analyzed CMV epidemiology in a large cohort of pediatric renal transplant recipients (n = 242) and assessed the impact of antiviral chemoprophylaxis with valganciclovir (VGCV) or ganciclovir (GCV) on CMV replication and morbidity. Results While antiviral chemoprophylaxis with VGCV or GCV in patients with a high (D+/R−) or intermediate (D+/R+) CMV risk (n = 82) compared to preemptive therapy (n = 47) had no significant effect on the incidence of CMV syndrome or tissue-invasive disease, chemoprophylaxis was associated with a better preservation of transplant function at 3 years posttransplant (loss of estimated glomerular filtration rate in the chemoprophylaxis cohort, 16.0 ± 3.4 vs. 30.1 ± 4.7 mL/min per 1.73 m2 in the preemptive therapy cohort, P < 0.05).CMV replication was associated with a more pronounced decline of graft function (difference in estimated glomerular filtration rate of 9.6 mL/min per 1.73 m2 at 3 years) compared to patients without CMV replication. However, patients undergoing VGCV or GCV chemoprophylaxis had more leukocytopenia. Conclusion Antiviral chemoprophylaxis with VGCV or GCV in recipients with a high or moderate CMV risk is associated with a better preservation of transplant function. Hence, the prevention of CMV replication in this patient population has the potential to improve transplant outcome.
American Journal of Transplantation | 2016
Britta Höcker; S Zencke; Lars Pape; Kai Krupka; Lennart Köster; Alexander Fichtner; L Dello Strologo; Isabella Guzzo; Rezan Topaloglu; Birgitta Kranz; Jens König; Martin Bald; Nicholas J. A. Webb; Aytül Noyan; Hasan Dursun; Stephen D. Marks; Z B Ozcakar; Florian Thiel; Heiko Billing; M Pohl; Henry Fehrenbach; Paul Schnitzler; Thomas Bruckner; T Ahlenstiel-Grunow; Burkhard Tönshoff
In order to investigate the hypothesis that the mammalian target of rapamycin inhibitor everolimus (EVR) shows anticytomegalovirus (CMV) activity in pediatric patients, we analyzed the impact of EVR‐based immunosuppressive therapy on CMV replication and disease in a large cohort (n = 301) of pediatric kidney allograft recipients. The EVR cohort (n = 59), who also received low‐dose cyclosporin, was compared with a control cohort (n = 242), who was administered standard‐dose cyclosporin or tacrolimus and an antimetabolite, mostly mycophenolate mofetil (91.7%). Multivariate analysis revealed an 83% lower risk of CMV replication in the EVR cohort than in the control cohort (p = 0.005). In CMV high‐risk (donor+/recipient−) patients (n = 88), the EVR‐based regimen was associated with a significantly lower rate of CMV disease (0% vs. 14.3%, p = 0.046) than the standard regimen. In patients who had received chemoprophylaxis with (val‐)ganciclovir (n = 63), the CMV‐free survival rates at 1 year and 3 years posttransplant (100%) were significantly (p = 0.015) higher in the EVR cohort (n = 15) than in the control cohort (n = 48; 1 year, 75.0%; 3 years, 63.3%). Our data suggest that in pediatric patients at high risk of CMV, an EVR‐based immunosuppressive regimen is associated with a lower risk of CMV disease than a standard‐dose calcineurin inhibitor–based regimen.
Pediatric Nephrology | 2016
Gonul Parmaksiz; Aytül Noyan; Hasan Dursun; Emine Ince; Ruksan Anarat; Nurcan Cengiz
BackgroundReflux nephropathy is the most serious complication of vesicoureteral reflux (VUR). The aim of this study was to assess the role of urinary levels of neutrophil-gelatinase-associated lipocalin (NGAL),kidney injury molecule-1 (KIM-1), and liver-type fatty-acid-binding protein (L-FABP) in the early diagnosis of reflux nephropathy in patients with VUR.MethodsThis study assessed 123 patients with primary VUR and 30 healthy children as a control group. The children were divided into five groups: Group A, patients with VUR and renal parenchymal scarring (RPS); Group B, patients with VUR and without RPS; Group C, patients with RPS and resolved VUR; Group D, patients with resolved VUR and without RPS; Group E, healthy reference group.ResultsMedian urinary NGAL (uNGAL)/Creatinine (Cr) was significantly higher in patients with than those without RPS and the control group (p = 0.0001). Median uKIM-1/Cr was similar in all groups (p = 0.417). Median uL-FABP/Cr was significantly higher in patients with RPS than in the reference group (p < 0.05).ConclusionsUrinary NGAL levels may be used as a noninvasive diagnostic marker for predicting renal scarring in reflux nephropathy.
Journal of Pediatric Urology | 2015
Aytül Noyan; Gonul Parmaksiz; Hasan Dursun; Semire Serin Ezer; Ruksan Anarat; Nurcan Cengiz
INTRODUCTION The clinical tests currently in use for obstructive nephropathy (such as renal ultrasonography, differential radionuclide renal scans and urinary creatinine concentration data) are not efficient predictors of the subsequent clinical course. Novel and simple biomarkers are required which, if proven, could be clinically beneficial in determining if a patient is eligible for surgery or reno-protective therapy. More recently, the interest of clinicians has focused on the potential of urinary neutrophil gelatinase-associated lipocalin (uNGAL), urinary kidney injury molecule-1 (uKIM-1) and urinary liver-type fatty acid-binding proteins (uL-FABP) as biomarkers for renal function in children with hydronephrosis (HN). OBJECTIVE The purpose of this study was to investigate possible clinical applications of uNGAL, uKIM-1 and uL-FABP as beneficial non-invasive biomarkers to determine whether or not surgical intervention is required in children with HN. STUDY DESIGN Renal ultrasonography and radionuclide renal scans were used as diagnostic tools to detect HN. Patients were divided into two groups based on the antero-posterior diameter of their renal pelvis and the presence of dysfunction. Group 1 included 26 children with severe HN (with dysfunction), and group 2 consisted of 36 children with mild HN (without dysfunction). Urine samples were collected from 62 children with HN and 20 healthy children. RESULTS Hydronephrosis was more common in males than in females, with a male to female ratio of 9:1 in the study sample. The incidence of left kidney involvement (32 patients) was slightly higher than right kidney involvement (28 patients). Compared with controls and group 2, the ratio of uNGAL to creatinine was significantly higher in group 1 (p < 0.05). The biomarker uNGAL/Cr exhibited fairly good diagnostic accuracy, with an area under the curve of 0.68 [95% confidence interval 0.6-0.7] and an optimal cut-off value of 0.16 ng/mg Cr (sensitivity 58%, specificity 75%) (p < 0.05). There was a positive correlation between the uNGAL/Cr ratio and the uKIM-1/Cr ratio (r = 0.582, p < 0.05) and uL-FABP/Cr ratio (r = 0675, p < 0.05) in group 1. DISCUSSION The results clearly demonstrated that children with hydronephrosis and dysfunction had significantly increased uNGAL, and uNGAL/Cr concentrations. However, uKIM-1, uKIM-1/Cr, uL-FABP and uL-FABP/Cr concentrations were not significantly different when compared with controls. These results support the use of uNGAL concentrations as an early marker for renal dysfunction in HN. CONCLUSIONS The study clearly demonstrated that pediatric patients with hydronephrosis and dysfunction had significantly higher uNGAL to creatinine concentrations as compared with controls.
Clinical Nephrology | 2006
Buyukcelik M; Cengiz N; Dursun H; Soran M; Bayazit Ak; Aytül Noyan; Ali Anarat
AIMS We herein report the results of intravenous pulse cyclophosphamide (IVCP) therapy of 5 patients with steroid-resistant focal segmental glomerulosclerosis (FSGS). All patients had been treated with oral and intravenous pulse methylprednisolone and failed to respond to steroids from onset and were considered as primary steroid-resistant. Before starting IVCP, all patients were also treated with other immunosuppressive drugs with or without steroids, but none of them responded to such therapies and no patient had any NPSH2 gene mutations. METHODS IVCP was given monthly at a dose of 500 mg/m2 for 6 months. At the end of 6 months, IVCP was discontinued in case there was no response. Otherwise, IVCP was continued for every 2 months. Oral prednisone was given concurrently at 60 mg/m2 daily for 6 weeks and then 40 mg/m2 on alternate days for 4 weeks. Prednisone was then tapered to 10 mg/m2 alternate days and continued during the therapy period. RESULTS Only 1 of these patients achieved remission after IVCP while 4 patients showed no response to IVCP. 2 patients who did not achieve remission progressed to end-stage renal disease (ESRD) and 2 others who had not been treated with cyclosporine before underwent cyclosporine therapy. None of our patients has suffered from adverse effects of IVCP. CONCLUSION We found that IVCP had a limited beneficial effect in treatment of steroid-resistant FSGS and it may be suggested that IVCP can be tried to treat steroid-resistant patients, also for patients with primary steroid resistance and those who do not respond to other immunosuppressive therapies.
Pediatric Transplantation | 2017
Sandra Habbig; Ruth Volland; Kai Krupka; Uwe Querfeld; Luca Dello Strologo; Aytül Noyan; Fatoş Yalçınkaya; Rezan Topaloglu; Nicholas J. A. Webb; Markus J. Kemper; Lars Pape; Martin Bald; Birgitta Kranz; Christina Taylan; Britta Höcker; Burkhard Tönshoff; Lutz T. Weber
Dyslipidemia contributes to cardiovascular morbidity and mortality in pediatric transplant recipients. Data on prevalence and risk factors in pediatric cohorts are, however, scarce. We therefore determined the prevalence of dyslipidemia in 386 pediatric renal transplant recipients enrolled in the CERTAIN registry. Data were obtained before and during the first year after RTx to analyze possible non‐modifiable and modifiable risk factors. The prevalence of dyslipidemia was 95% before engraftment and 88% at 1 year post‐transplant. Low estimated glomerular filtration rate at 1 year post‐transplant was associated with elevated serum triglyceride levels. The use of TAC and of MPA was associated with significantly lower concentrations of all lipid parameters compared to regimens containing CsA and mTORi. Immunosuppressive regimens consisting of CsA, MPA, and steroids as well as of CsA, mTORi, and steroids were associated with a three‐ and 25‐fold (P<.001) increased risk of having more than one pathologic lipid parameter as compared to the use of TAC, MPA, and steroids. Thus, amelioration of the cardiovascular risk profile after pediatric RTx may be attained by adaption of the immunosuppressive regimen according to the individual risk profile.
Journal of Clinical Apheresis | 2014
Ilknur Kozanoglu; Suat Kahveci; Süheyl Asma; Mahmut Yeral; Aytül Noyan; Can Boga; Hakan Ozdogu
Acute poisoning is an important cause of morbidity and mortality during childhood. This manuscript reports the positive outcome of a pediatric case with a history of accidental carbamazepine intake treated using plasma exchange. A 3‐year‐old male presented with severe carbamazepine intoxication. He was comatose and had generalized tonic clonic seizure, ventricular tachycardia, and hypotension. Although he did not respond to classical therapies, we performed two sessions of plasma exchange. The patient recovered rapidly and was discharged from the hospital six days from the time of carbamazepine ingestion with no complication or neurologic impairment. Plasma exchange can be performed safely in very small children, and it might be the first line treatment, particularly for intoxication with drugs that have high plasma‐protein‐binding properties. J. Clin. Apheresis 29:178–180, 2014.
Clinical Nephrology | 2008
Simsek B; Aytül Noyan; Bayazit Ak; Soran M; Ali Anarat
Pleural effusions are seen relatively common in end-stage renal disease (ESRD) patients, on the other hand, hydrothorax secondary to pleuroperitoneal leak in continuous ambulatory peritoneal dialysis (CAPD) patients is rare. Since treatment modalities differ widely from that of other causes of pleural effusion seen in CAPD patients such as uremia, volume overload, congestive heart failure, infection and malignancy, pleuroperitoneal leak should always be kept in mind in the differential diagnosis and should be excluded urgently. To draw attention to this point, in this paper, 2 children on CAPD who developed a hydrothorax secondary to a pleuroperitoneal communication are presented with an overview of diagnostic tools and treatment modalities.
Diagnostic Microbiology and Infectious Disease | 2014
Sule Colakoglu; Hasan Dursun; Nurcan Cengiz; Meryem Cosar Bulat; Aytül Noyan
In renal transplant recipients, BK polyomavirus (BKV) is linked to nephropathy. BK virus genotypes have a strong geographic component. This paper presents the African variant of BKV in a Turkish renal transplant patient, which is a rare cause of infection in the Northern Hemisphere and, to our knowledge, the first case from Turkey.