Oktay Ozkan
Istanbul University
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Transplantation Proceedings | 2011
Halil Yazici; Yasar Caliskan; S. Öztürk; Oktay Ozkan; Aydin Turkmen; Mehmet Sukru Sever
BACKGROUND Reflux nephropathy (RN) has an important place among the etiologies of end-stage renal disease (ESRD). In this retrospective study we sought to analyze posttransplantation complications among renal transplant recipients whose primary disease was RN. METHODS Seven hundred forty-five patients who underwent transplantation in our institution between 1983 and 2006 were included in the study. The outcomes of patients with RN (Group 1) were compared with a control group (Group 2) that consisted of age-matched, nondiabetic patients whose primary disease was chronic glomerulonephritis or unknown etiologies. RESULTS Group 1 consisted of 52 patients, including 20 males with a mean overall age of 25 years. Group 2 included 47 patients, including 21 males with a mean age of 27 years. There was no significant difference with regard to age, gender, donor type, donor age, modality of hemodialysis, or HLA match between the 2 groups. Group 1 graft survival rates in the first and fifth years were 95% and 90%, respectively, and in Group 2 they were 86% and 70%, respectively (P = .302 and P = .072, respectively). There was no significant difference with respect to follow-up duration, hospital stay, or incidence of biopsy-proven or clinically suspected acute rejection episodes between the groups. During the 6-year follow-up, the incidence of biopsy-proven chronic allograft nephropathy was the same in both groups. One patient in Group 1 and 2 in Group 2 died of cardiovascular issues; 1 Group 2 patient died of infection. The frequency of urinary tract infection in Group 1 was greater than that of Group 2 (40% vs, 23%; P = NS). CONCLUSION Despite the higher incidence of urinary tract infections, there was no significant difference in posttransplantation complications or patient and graft survival rates between RN patients compared with the control group.
Artificial Organs | 2010
Berna Yelken; Yasar Caliskan; Oktay Ozkan; Numan Gorgulu; Halil Yazici; Aydin Turkmen; Mehmet Sukru Sever
Maintenance immunosuppression with calcineurin inhibitors (CNI) following renal transplantation is associated with nephrotoxicity and accelerated graft loss. Sirolimus (SRL) is a nonnephrotoxic immunosuppressive agent. We retrospectively analyzed our experience with kidney transplant recipients who were converted from CNI to SRL. A total of 58 renal transplant recipients were converted from CNI to SRL. SRL was started at a dose of 0.075 mg/kg and, at the same time, CNI dose was reduced by 50% daily for 3 days. SRL trough levels were targeted between 8 and 12 ng/mL. When target trough levels were achieved, CNI was withdrawn. The main indications for switching were posttransplant malignancies (n = 32) and chronic allograft nephropathy (CAN) (n = 10). The mean time from transplantation to conversion was 84 +/- 71 months. Mean serum creatinine level was 1.63 +/- 0.52 mg/dL before conversion. Serum creatinine levels at the 1, 3, 6 months, and 1, 2, 3 years after conversion were 1.64 +/- 0.58 mg/dL (P = 0.67), 1.52 +/- 0.53 mg/dL (P = 0.414), 1.62 +/- 0.62 mg/dL (P = 0.734), and 1.48 +/- 0.58 mg/dL (P = 0.065), 1.58 +/- 0.53 mg/dL (P = 0.854), 1.88 +/- 0.77 mg/dL (P = 0.083), respectively. Daily proteinuria levels increased from 0.04 +/- 0.11 g/day at baseline to 0.55 +/- 1.33 g/day (P = 0.037) after conversion, in the responders group. In the nonresponders group, baseline proteinuria was 0.13 +/- 0.25 g/day, and increased to 1.44 +/- 2.44 g/day after conversion (P = 0.008). SRL was discontinued in 16 patients (31%) because of the occurrence of severe side effects. The proportion of patients remaining on SRL therapy over time was 43.1% at 1 year, 15.5% at 2 years after conversion, and 10.3% at 3 years after conversion. SRL conversion may be very useful in patients suffering from neoplasia; however, frequent side effects related with this intervention should be considered, and routine conversion from CNI to SRL to reduce nephrotoxicity should be discouraged.
World journal of nephrology | 2016
Meltem Gursu; Sami Uzun; Derya Topçuoğlu; Leyli Kadriye Koc; Lamiye Yucel; Abdullah Sumnu; Egemen Cebeci; Oktay Ozkan; Ahmet Behlul; Leyla Koç; Savaş Öztürk; Rumeyza Kazancioglu
AIM To examine all skin changes in peritoneal dialysis (PD) patients followed up in our unit. METHODS Patients on PD program for at least three months without any known chronic skin disease were included in the study. Patients with already diagnosed skin disease, those who have systemic diseases that may cause skin lesions, patients with malignancies and those who did not give informed consent were excluded from the study. All patients were examined by the same predetermined dermatologist with all findings recorded. The demographic, clinical and laboratory data including measures of dialysis adequacy of patients were recorded also. Statistical Package for Social Sciences (SPSS) for Windows 16.0 standard version was used for statistical analysis. RESULTS Among the patients followed up in our PD unit, those without exclusion criteria who gave informed consent, 38 patients were included in the study with male/female ratio and mean age of 26/12 and 50.3 ± 13.7 years, respectively. The duration of CKD was 7.86 ± 4.16 years and the mean PD duration was 47.1 ± 29.6 mo. Primary kidney disease was diabetic nephropathy in 11, nephrosclerosis in six, uropathologies in four, chronic glomerulonephritis in three, chronic pyelonephritis in three, autosomal dominant polycystic kidney disease in three patients while cause was unknown in eight patients. All patients except for one patient had at least one skin lesion. Loss of lunula, onychomycosis and tinea pedis are the most frequent skin disorders recorded in the study group. Diabetic patients had tinea pedis more frequently (P = 0.045). No relationship of skin findings was detected with primary renal diseases, comorbidities and medications that the patients were using. CONCLUSION Skin abnormalities are common in in PD patients. The most frequent skin pathologies are onychomycosis and tinea pedis which must not be overlooked.
Renal Failure | 2016
Serhat Karadag; Elif Sakçı; Sami Uzun; Zeki Aydin; Egemen Cebeci; Abdullah Sumnu; Oktay Ozkan; Mehmet Yamak; Macit Koldas; Ahmet Behlul; Meltem Gursu; Esra Ataoglu; Savaş Öztürk
Abstract Vaspin, a recently identified adipokine, is a visceral adipose tissue-derived serine protease inhibitor that may have insulin sensitizing effect on adipose tissue. Herein, we measured vaspin level in patients with different stages of diabetic nephropathy (DNP), and investigated the correlation of the vaspin level with other inflammatory parameters. 106 adult type 2 diabetic patients with no known chronic inflammatory disease were included and grouped according to the stage of DNP: Albuminuria <30 mg/day and estimated glomerular filtration rate (eGFR) > 60 mL/min/1.73m2 (Group-1); albuminuria 30–300 mg/day and eGFR >60 mL/min/1.73m2 (Group-2); albuminuria >300 mL/min and eGFR <60 mL/min/1.73m2 (Group-3). Demographic, clinical and laboratory data were recorded as well as vaspin, high sensitivity C-reactive protein (hsCRP), interleukin (IL)-1 and tumor necrosis factor (TNF)-α levels. There were 38, 35 and 33 patients in Group 1, 2 and 3, respectively. Groups were similar regarding age and gender. Vaspin level did not differ between groups. When all the groups were considered, vaspin was positively correlated with IL-6 level (r = 0.215, p = 0.041). No correlation of vaspin was found with IL-1, TNF-α and hsCRP levels (p = 0.580, r = 0.054; p = 0.463, r = 0.072; p = 0.812, r = 0.025, respectively). Vaspin levels of the patients with GFR ≥60 mL/min/1.73m2 was less than that of patients with GFR <60 mL/min/1.73m2 (p = 0.03). Age and IL-6 were found to be the major determinants of vaspin level with linear regression analysis. In patients with DNP, vaspin level does not change within the early stages of DNP; while it is higher in patients with decreased GFR, which may be related with increasing inflammation regardless of the stage of the kidney disease.
Case reports in nephrology | 2015
Egemen Cebeci; Secil Demir; Meltem Gursu; Abdullah Sumnu; Mehmet Yamak; Baris Doner; Serhat Karadag; Sami Uzun; Ahmet Behlul; Oktay Ozkan; Savas Ozturk
Klippel Trenaunay Weber syndrome (KTWS) is a rare disease characterized by hemihypertrophy, variceal enlargement of the veins, and arteriovenous (AV) malformations. Renal involvement in KTWS is not known except in rare case reports. Herein, we present a case of KTWS with nephrotic syndrome. A 52-year-old male was admitted due to dyspnea and swelling of the body for the last three months. The pathological physical findings were diffuse edema, decreased lung sounds at the right basal site, increased diameter and decreased length of the left leg compared with the right one, diffuse variceal enlargements, and a few hemangiomatous lesions on the left leg. The pathological laboratory findings were hypoalbuminemia, hyperlipidemia, increased creatinine level (1.23 mg/dL), and proteinuria (7.6 g/day). Radiographic pathological findings were cystic lesions in the liver, spleen, and kidneys, splenomegaly, AV malformation on the left posterolateral thigh, and hypertrophy of the soft tissues of the proximal left leg. He was diagnosed to have KTWS with these findings. Renal biopsy was performed to determine the cause of nephrotic syndrome. The pathologic examination was consistent with focal segmental sclerosis (FSGS). He was started on oral methylprednisolone at the dosage of 1 mg/kg and began to be followedup in the nephrology outpatient clinic.
International Journal of Artificial Organs | 2016
Sami Uzun; Burcu Kaya; Kenan Çelik; Ahmet Behlul; Oktay Ozkan; Melike Kuvvet; Yasemin Erdogan Doventas; Meltem Gursu; Serhat Karadag; Abdullah Sumnu; Egemen Cebeci; Burak Kocak; Aydin Turkmen; Savaş Öztürk
Background Midkine (MK), which is expressed in the proximal tubular epithelial cells of the kidney, is thought to have a role in the pathophysiology of inflammation-related renal diseases. Both immunological and nonimmunological mechanisms may affect renal functions negatively during the early and late post-transplantation periods. We aimed in our study to evaluate the relationship of MK with clinical findings and inflammatory markers, including high sensitivity C-reactive protein (hs-CRP), interleukin (IL-6) and tumor necrosis factor (TNF-α) in the pretransplant and post-transplant period. Methods Forty-one consecutive patients transplanted from living related donors were included in this prospective observational study. All patients received the same immunosuppressive treatment protocol. MK, hsCRP, IL-6 and TNF-α levels were measured before and 2 months after renal transplantation. Results Pretransplant MK levels correlated positively with hsCRP (r = 0.41, p = 0.004) and IL-6 (r = 0.58, p<0.001). The mean post-transplant MK level was found to be higher than the pretransplant level (143 ± 350 pg/mL, 2792 ± 4235 pg/mL respectively, p = <0.001), while the mean hsCRP, IL-6 and TNF-α levels did not change significantly. Post-transplant IL-6 correlated significantly with MK (r = 0.388, p = 0.012), hsCRP (r = 0.41, p = 0.007) and TNF-α (r = 0.348, p = 0.026). There was no significant correlation between clinical findings and inflammatory markers. Conclusions MK may be a good inflammatory marker in renal transplant recipients as in other inflammatory diseases. Moreover, it seems that it is not affected by factors other than inflammation during the post-transplantation period.
Turkish Nephrology Dialysis Transplantation | 2013
Meltem Gursu; Savas Ozturk; Hatice Küçük; Zeki Aydin; Fuat Sar; Halil Yazici; Mehmet Küçük; Oktay Ozkan; Aydin Turkmen; Rumeyza Kazancioglu
ObJECTIVE: The primary objective of our study was to investigate effects of antiproteinuric treatment on lipid levels of patients with idiopathic focal segmental glomerulosclerosis (FSGS) or membranous glomerulonephritis (MGN). MATERIAL and METHODS: The clinical and laboratory data of the patients were recorded at three-month intervals during 18 months of follow-up. Patients with non-nephrotic proteinuria without hypoalbuminemia received conservative treatment while those with more severe disease received steroid therapy as well. Lipid parameters in the two groups and the factors effective on these parameters were investigated. RESULTS: Sixty eight patients (36 with FSGS, 32 with MG) were included. The mean age of the patients and the follow-up period were 39.6±16.6 years and 16.4±8.9months, respectively. 36 (53%) patients received steroid therapy. The percentage of patients taking antilipemic treatment was
Transplantation Proceedings | 2006
Yasar Caliskan; M. Demirturk; A.A. Cagatay; D. Guven; Oktay Ozkan; T. Ecder; Aydin Turkmen; Mehmet Sukru Sever
Nephrology Dialysis Transplantation | 2006
Yasar Caliskan; Savas Ozturk; Mustafa Demirtürk; Oktay Ozkan; Halil Yazici; Tevfik Ecder; Aydin Turkmen; Mehmet Sukru Sever
Turkish Nephrology Dialysis Transplantation | 2014
Meltem Gursu; Zeki Aydin; Savas Ozturk; Serhat Karadag; Sami Uzun; Yasemin Doventas Erdogan; Macit Koldas; Abdullah Sumnu; Egemen Cebeci; Oktay Ozkan; Rumeyza Kazancioglu