Tamer Sakaci

Sisli Etfal Training and Research Hospital, İstanbul, Istanbul, Turkey

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Publications (22)27.05 Total impact

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    ABSTRACT: Amyloid A (AA) amyloidosis is a multisystem, progressive and fatal disease. Renal involvement occurs early in the course of AA. We aimed to investigate the etiology, clinical and laboratory features, and outcome of patients with biopsy-proven renal AA amyloidosis.
    Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciences. 07/2014; 19(7):644-9.
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    ABSTRACT: Disordered mineral metabolism is implicated in the pathogenesis of vascular calcification in hemodialysis (HD) patients. Fibroblast growth factor 23 (FGF-23) is the main regulator of phosphate metabolism. In this prospective study, we aimed to investigate the association of serum FGF-23 with progression of coronary artery calcification in HD patients. Seventy-four HD patients(36 male/38 female,mean age:52 +/- 14 years) were included. Serum FGF-23 levels were measured by ELISA. Coronary artery calcification score(CACS) was measured twice with one year interval. Patients were grouped as progressive (PG)(36 patients-48%) and non-progressive (NPG). Age, serum phosphorus, baseline and first year CACS were found to be significantly higher in the PG compared to NPG group. Serum FGF-23 levels were significantly higher in PG [155 (80--468) vs 147 (82--234), p = 0.04]. Patients were divided into two groups according to baseline CACS (low group, CACS <= 30; high group, CACS > 30). Serum FGF-23 levels were significantly correlated with the progression of CACS (DeltaCACS) in the low baseline CACS group (r = 0.51, p = 0.006), but this association was not found in high baseline CACS group (r = 0.11, p = 0.44). In logistic regression analysis for predicting the PG patients; serum FGF-23, phosphorus levels and baseline CACS were retained as significant factors in the model. Serum FGF-23 was found to be related to progression of CACS independent of serum phosphorus levels. FGF-23 may play a major role in the progression of vascular calcification especially at the early stages of calcification process in HD patients.
    BMC Nephrology 11/2013; 14(1):241. · 1.64 Impact Factor
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    ABSTRACT: Aim: To evaluate the clinical outcome, identify predictors of patient and technique survival in our peritoneal dialysis (PD) patients in the western region of Turkey. Methods: We included all patients who initiated therapy between 2001 and 2010. Socio-demographic characteristics such as who helped to administer the PD as well as conditions under which PD was chosen by patients were investigated from patients' files. Hemodialysis (HD) history and duration, additional systemic diseases, and end-stage renal disease etiologies of all patients were recorded. Clinical data such as blood pressure, amount of ultrafiltration, and laboratory parameters were evaluated before initiation of PD and during the last monitoring period. Infectious complications and their incidences were investigated. Patient and technique survival were investigated for every patient. Results: 322 patients started PD treatment during the study period. 23 patients were excluded. Data from the remaining 299 patients (167 female, mean follow-up time 38.5 ± 26.8 months, mean age 44.7 ± 15.9 years) were evaluated retrospectively. It was determined that 87.3% of the patients made their PD exchanges without help from anyone. 79.9% of patients chose PD as their personal preference. 48 patients had HD history before PD. Peritonitis incidences and catheter exit site/tunnel infection attacks were 27 ± 23 and 32.3 ± 24.9 patient-months, respectively. During the follow-up period, 199 patients (80 patients transferred to HD, 78 patients died and, 41 patients had transplantation) were withdrawn from PD. The most frequent causes of death were cardiovascular events and peritonitis and/or sepsis, whereas most frequent causes of transfer to HD were peritonitis and/or sepsis. Mean survival time was 49.9 ± 2.6 months. The estimation of survival rate was 85.2%, 66.5% and 45.3% at 1, 3, and 5 years, respectively. Preference for PD (RR: 4.77, p < 0.001), presence of HD history (RR: 2.08, p = 0.04), presence of diabetes mellitus (RR: 2.13, p = 0.01), low pretreatment serum albumin (RR: 0.32, p < 0.001), and low serum parathormone levels at last visit (RR: 0.99, p = 0.04) were predictors of mortality. Mean technique survival duration was 48.5 ± 2.4 months. The estimation of technique survival by Kaplan-Meier analyses was 92%, 67% and 43% at 1, 3, and 5 years, respectively. Technique survival was associated with preference for PD (RR: 0.45, p < 0.001), presence of diabetes mellitus (RR: 1.92, p = 0.003), and pretreatment serum albumin levels (RR: 0.58, p = 0.003). Conclusion: Patient survival in the presented institute is similar to that reported in Western countries. Compulsory choice of PD, presence of HD history, presence of diabetes, low pretreatment serum albuminm, and low serum parathormone levels at last visit were the strongest predictors of death. Risk factors for technique failure were compulsory choice of PD, presence of diabetes, low pretreatment serum albumin.
    Clinical nephrology 07/2013; · 1.29 Impact Factor
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    ABSTRACT: To investigate the impacts of infectious complications on mortality and morbidity; and to identify the other potential factors effective in mortality in peritoneal dialysis (PD) patients. We included patients who initiated therapy between 2001-2011. Patients were divided into two groups regarding to presence or absence of infectious complications. Socio-demographic data and clinical courses were compared and the reasons for PD withdrawal were obtained. Survival analysis of all patients was performed and the effects of infectious complications on mortality were investigated. 301 patients were included in this retrospective study. 214 patients (mean follow-up time 28.7±16.5 months) had infection history, 87 patients (mean follow-up time 48.9±29.6 months) had no infection history. There were no statistically significant difference in comparison of the groups in terms age, gender, education levels, hemodialysis history. In patients with infection history, 465 peritonitis and 213 catheter exit site infection attacks were diagnosed. The most frequently agent was methicillin-sensitive Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus in both conditions, while 25% of catheter exit site infection and 25% of peritonitis attacks were culture negative. During follow-up period, 60 patients transferred to hemodialysis, 58 patients died, 18 patients had renal transplantation in patients with infection history. In other group, 27 patients died, 23 patients had renal transplantation and 11 patients transferred to hemodialysis. Mean survival times were 56.3±2.8 months in patients with infection history and 86.8±6.1 months in other group. Mortality rate was found higher in patients with infection history (long-rank: 0.030). PD preference (OR: 5.213, p < 0.001), pretreatment low serum albumin (OR: 0.378, p = 0.001), low hemoglobin levels (OR: 0.810, p = 0.029) were found as predictors of survival in patients with infection history. Infectious complications have negative effects on patient survival. Nature of PD preference, initial hypoalbuminemia and anemia were found to increase the mortality rate. The major causes of deaths were peritonitis and/or sepsis in patients with infectious complications, while the major cause of death was cardiac reasons in patients without infectious complications.
    European review for medical and pharmacological sciences 04/2013; 17(8):1064-72. · 1.09 Impact Factor
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    ABSTRACT: INTRODUCTION: Diagnosis of tuberculosis (TB) among dialysis patients may be difficult because of increased frequency of extra-pulmonary presentations, atypical clinical manifestations, and non-specific symptoms. This study aimed to investigate the spectrum of clinical presentations and outcome in dialysis patients during a nine-year period. METHODOLOGY: A total of 651 patients undergoing hemodialysis (HD) and peritoneal dialysis (PD) for at least three months in our unit between 2001 and 2010 were studied. Dialysis and follow-up were performed in our tertiary care center located in the eastern region of Turkey. Diagnosis of TB was established by combining clinical, radiological, biochemical, microbiological, and histological findings. Choice of anti-TB drug used, the results of therapy, and patient outcome were noted. RESULTS: Out of 651 dialysis patients studied, 322 (49.4%) were on PD and the remainder on HD (50.6%). Twenty-six (4%) of the 651 dialysis patients were diagnosed with TB (15 PD, 11 HD), 5 of whom were diagnosed by microbiological assessment, 9 by pathological assessment, and 12 by clinical and radiological findings. Mean age at diagnosis was 41.5 ± 16.5 years and the female/male ratio was 1.18. Three patients had a history of pulmonary TB. Extra-pulmonary involvement was observed in 17 (65.4%) patients. All patients were treated with rifampicin isoniazid, ethambutol, pyrazinamide and pyridoxine. Four patients died during the study. CONCLUSION: TB occurred in dialysis patients and extra-pulmonary TB was more commonly identified than pulmonary TB. Tuberculous lymphadenitis was the most frequent form of extra-pulmonary TB in our cohort.
    The Journal of Infection in Developing Countries 03/2013; 7(3):208-213. · 1.00 Impact Factor
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    ABSTRACT: Background: To investigate the effects of ESRD etiologies on mortality in peritoneal dialysis patients. Methods: We included patients who initiated therapy between 2001-2011 and classified them according to etiologies including amyloidosis, diabetes mellitus, chronic glomerulonephritis and polycistic renal disease. Socio-demographic data, clinical courses and infectious complications were compared between groups, and the reasons for peritoneal dialysis withdrawal were recorded. Patient and technique survival analysis were performed. Results: 354 patients were included to the study. Thereafter, 154 patients were excluded. Totally, 29 patients with AA-amyloidosis (mean age 37.9±16.4 years, follow-up time 21.7±20.2 months), 78 patients with diabetes mellitus (mean age 56.9±13.6 years, follow-up time 35±28.6 months), 68 patients with chronic glomerulonephritis (mean age 37.2±12 years, follow-up time 47.7±29.9 months), 29 patients with polycystic renal disease (mean age 35.6±13.8 years, follow-up time 45.4±36.8 months) were evaluated. Albumin level was lower in patients with amyloidosis at initiation and the end of study (for both p<0.001). Incidence of peritonitis and catheter exit site/tunnel infection attacks were higher in patients with amyloidosis (p=0.002 and 0.018 respectively). There was statistical difference among groups with respect to the last status of patients (p<0.001). Deaths were frequent in amyloidotic and diabetic patients. The majority of deaths were due to peritonitis and/or sepsis and, cardiovascular reasons. The mortality rate was found higher in patients with amyloidosis (log rank=0.005), especially at first 2-3 years. Presence of anyone helping to administer peritoneal dialysis(OR:6.244, p=0,025), initial serum albumin level(OR:0.352, p=0,034) and presence of catheter exit site/tunnel infection(OR:0.250, p=0,015) were independent predictors of patient survival. Conclusion: Renal failure etiology has effects on peritoneal dialysis patients' survival. Patients with amyloidosis have the worst survival. Because of loss of PD survival advantage seen in first years of therapy in patients with amyloidosis, peritoneal dialysis may not be suitable as first choice therapy in this group.
    Kidney and Blood Pressure Research 11/2012; 36(1):182-190. · 1.60 Impact Factor
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    ABSTRACT: The aim of the study was to investigate the effects of rosiglitazone treatment on insulin resistance (IR) and tumor necrosis factor-alpha (TNF-alpha) levels in non-diabetic chronic kidney disease (CKD) patients with IR. Thirty non-diabetic CKD patients with IR were enrolled in the study. Patients were grouped into two: group 1 (n = 15) received rosiglitazone 4 mg tablet for 3 months and patients who did not receive rosiglitazone treatment constituted the group 2 (n = 15). Baseline and after rosiglitazone treatment, homeostatis model assessment-insulin resistance (HOMA-IR) and TNF-alpha levels were measured. There were no statistical differences in gender, age, HOMA-IR and TNF-alpha levels among group 1 and group 2 (p > 0.05 for all). Compared to baseline in group 1, significant differences were found in HOMA-IR and TNF-alpha levels after 3 months (p = 0.023; p = 0.001, respectively). Our study indicates that, rosiglitazone treatment improves the IR and decreases TNF-alpha levels in non-diabetic patients CKD with IR.
    European review for medical and pharmacological sciences 11/2012; 16(11):1519-24. · 1.09 Impact Factor
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    ABSTRACT: Fungal peritonitis (FP) is a rare but serious complication in patients undergoing peritoneal dialysis (PD), and is associated with higher morbidity, mortality. We aimed to analyze the predisposing factors, etiological agents, outcome and treatment of FP in patients with PD. We evaluated retrospectively all PD patients PD center between 2001 and 2011. Sixteen patients with FP were included into the study. The clinical records of 16 patients with FP among 355 patients were reviewed for the clinical and laboratory data. Among 506 episodes of PD-related peritonitis in 10 years, we identified 16 episodes of FP. Median PD duration was 36.7±22.2 months. In 87.5% of patients had one or more previous episode of bacterial peritonitis that were treated with multipl broad-spectrum antibiotics. FP was primary infection in five patients, whereas eleven patients experienced FP during the course of treatment of bacterial peritonitis. Six patients died due to the fungal infection whereas others were transferred to haemodialysis. Treatment of bacterial peritonitis with broad spectrum antibiotics was an important risk factor predisposing to the development of FP. The catheter removal and initiation of antifungal therapy as soon as possible are obligatory in episode of FP because it is responsible from high mortality rate.
    European review for medical and pharmacological sciences 11/2012; 16(12):1696-700. · 1.09 Impact Factor
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    ABSTRACT: Background/aims: A few patients stay on peritoneal dialysis (PD) for 5 years or longer from initiation of therapy. We investigated patient survival and factors affecting mortality in PD patients. Methods: This was a retrospective study including 354 PD patients. The demographic, clinical, and biochemical data were collected from the medical records. Two hundred patients were excluded. Evaluation was carried out on data from 154 patients, including 83 surviving 5 years or more and 71 who were taken as surviving less than 5 years. Results: Mean age, number of comorbid diseases, prevalence of diabetes mellitus (DM), rate of mandatory preference of PD, making their PD exchanges with help from anyone were lower in surviving patients, and education level was higher in surviving patients. Advanced age, high rate of mandatory preference of PD, high rate of baseline high, and high-average peritoneal transporters were associated with an increased risk of death. Conclusion: Long-term survival is possible for PD patients, particularly nondiabetics, those having higher education level, those with a self-preference of PD, and those making PD exchanges without any help.
    Renal Failure 09/2012; 34(9):1129-34. · 0.94 Impact Factor
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    ABSTRACT: Background : to evaluate the relationship between FGF23 and changes in biochemical parameters, left ventricle mass index, coronary, aortic and, valve calcifications. Methods : Totally 185 patients with chronic renal disease were included in this prospective, cross-sectional study. The patients were stratified according to GFR levels (mL/min/1.73m(2)) into 5 groups: ≥60, 45-59, 30-44, 15-29 and <15 (group 1-5 respectively).Biochemical parameters, serum FGF23 levels were measured. Echocardiographic assessments and Coronary artery calcification (CAC) with multidetector computerized tomography (MDCT) were done, left ventricle muscle mass (LVMI) was measured all patients. Results : Left ventricular hypertrophy (LVH), aortic and valve calcification were detected in 27.8%, 25.3% and 12% of patients respectively. CAC was detected in 18 patients. LVMI and FGF23 levels were found to increase proportionally with the severity of renal failure. A significant positive correlation between FGF-23 level and serum phosphate, log(PTH), and CaxP product was found. While a correlation between FGF-23 and valve calcification was detected, no correlation could be detected with LVMI, LVH, coronary and aortic calcification. Conclusion: In CKD, circulating FGF-23 and LVMI levels gradually increase with declining renal function such that by the time patients reach end-stage renal disease. Correlation between log(FGF23 )and valve calcification was significant, whereas no statistically significant relationship was found between log(FGF23 )and LVMI, LVH, aortic and coronary artery calcifications.
    Kidney and Blood Pressure Research 08/2012; 36(1):55-64. · 1.60 Impact Factor
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    ABSTRACT: The objective of this study was to examine the effects of angiotensin-converting enzyme inhibitors on peritoneal membrane transport, peritoneal protein loss, and proteinuria in peritoneal dialysis patients. Fifty-four peritoneal dialysis patients were included in the study. The patients were divided into two groups. Group 1 (n = 34) was treated with angiotensin-converting enzyme inhibitors. Group 2 (n = 20) did not receive any antihypertensive drugs during the entire follow-up. Eleven patients were excluded from the study thereafter. Thus, a total of 30 patients in Group 1 and 13 patients in Group 2 completed the study. We observed the patients for six months. Group 1 patients received maximal doses of angiotensin-converting enzyme inhibitors for six months. Parameters at the beginning of study and at the end of six months were evaluated. At the end of six months, total peritoneal protein loss in 24-hour dialysate effluent was significantly decreased in Group 1, whereas it was increased in Group 2. Compared to the baseline level, peritoneal albumin loss in 24-hour dialysate effluent and 4-hour D/P creatinine were significantly increased in Group 2 but were not significantly changed in Group 1. A covariance analysis between the groups revealed a significant difference only in the decreased amount of total protein loss in 24-hour dialysate. Proteinuria was decreased significantly in Group 1. This study suggests that angiotensin-converting enzyme inhibitors reduce peritoneal protein loss and small-solute transport and effectively protect peritoneal membrane transport in peritoneal dialysis patients.
    Clinics (São Paulo, Brazil) 08/2012; 67(8):877-83. · 1.59 Impact Factor
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    ABSTRACT: The aim of this study was to investigate the annual rate of glomerular filtration rate (GFR) decline and associated risk factors with this decline in diabetic nephropathy patients. A total of 122 type 2 diabetes mellitus (DM) patients (66F, mean follow up time 39 +/- 19 months, mean age 56 +/- 10 years, mean duration of diabetes diagnosis 12.1 +/- 9.5 years) between 2003 and 2010 were evaluated retrospectively. Socio-demographic characteristics and blood pressure data, laboratory parameters, HbAlc, daily urine protein excretion both of the first and last visits of all patients were recorded. Patients were separated into three groups according to rate of GFR decline. Group 1 (n:35), group 2 (n:42) and group 3 (n:45) consisted of patients < 1 ml/dk/1.73 m2, 1-5 ml/dk/1.73 m2 and > 5 ml/dk/1.73 m2 annual rate of GFR decline respectively. Demographics, laboratory data and their treatments were compared in all three groups and were investigated factors that may influence the rate of GFR decline. The annual rate of GFR decline was 1.4 +/- 2.3 ml/sec, -2.9 +/- 1.0 ml/sec and -11.9 +/- 9.1 ml/sec in group 1, 2 and 3 respectively. Daily urine protein excretion was 0.9 +/- 1.3, 1.2 +/- 1.5 and 5.2 +/- 5.5 g in groups respectively, was found significantly higher in group 3 (p < 0.001). Serum albumin level was significantly lower in group 3 (p < 0.001). We found positive correlation between annual rate of GFR decline and last visit systolic blood pressure (SBP), daily proteinuria and parathormone levels (r: 0.339, 0.447 and 0.289 p < 0.001, < 0.001 and 0.02 respectively) and negative correlation between GFR decline and deltaSBP (delta systolic blood pressure), pretreatment albumin, calcium and hemoglobin levels (r: -0.409, -0.526, -0.233 and -0.467, p < 0.001, < 0.001, < 0.001 and 0.016 respectively). Proteinuria, hypoalbuminemia, anemia, and a change in SBP were found most effective in annual rate of GFR decline in patients with diabetic nephropathy. The early detection of these factors may slow the progression of nephropathy.
    European review for medical and pharmacological sciences 07/2012; 16(7):878-83. · 1.09 Impact Factor
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    ABSTRACT: The aim of this study is to investigate the mortality and the factors which may affect it in patients who were transferred to peritoneal dialysis (PD) from hemodialysis (HD), compared to patients assigned to PD as first-line therapy. A total of 322 patients treated with PD between 2001 and 2010 were evaluated retrospectively. Twenty three patients were excluded and the data of remaining 299 patients (167F, mean follow up time 38.5±26.8 months, mean age 44.7±15.9 years) were evaluated. Patients were separated into two groups according to their HD history. Group 1 and group 2 consisted of patients with (n=48) and without (n=251) a history of prior HD, respectively. Socio-demographic characteristics such as who helped administer the PD and the preference of patients (compulsory vs their preference) were obtained from the patient records. The clinical data obtained during the last clinical evaluation before the initiation of PD (blood pressure, daily urine volumes, daily ultrafiltration amounts and laboratory parameters) were recorded. Additional systemic diseases and information about the etiologies of the end stage renal disease (ESRD) of all patients were recorded. Frequencies of the infectious complications were recorded. Patient and technique survival were investigated and compared between groups. In group 1, the patients were older and had less urine amounts (p=0.028 and 0.041 respectively). Thirty five patients (70%) and 25 patients (9.3%) have been transferred to PD due to vascular problems in group 1 and 2, respectively (p<0.001). In group 1, 37 (74%) patients were carrying out PD treatment by themselves, compared to 222 (88.4%) patients in group 2 (p=0.016). Incidences of peritonitis and catheter exit site/tunnel infection attacks were found 24.9±26.8 and 27.2±26.5 patient-months in group 1, and 27.4±22.4 and 33.4±24.5 patient-months in group 2, respectively (p=0.50 and 0.12). In group 1, twenty three patients have death and 2 patients have discontinued the treatment due to transplantation. In group 2, 174 patients have discontinued the treatment (55 patients have died, 80 patients have been switched to hemodialysis and 39 patients have received renal transplantation). There were significant differences between groups according to the last condition (p<0.001). Mean patient survival were found 22.9±4.2 and 55.5±2.8 patient-months in group 1 and group 2, respectively. The patient survival rates by Kaplan-Meier analysis were 50%, 40.9%, 27.3% and 9.1% at 1, 2, 3, and 4 years in group 1 and 90.9%, 81.6%, 73.9%, 64.9% and 53.1% at 1, 2, 3, 4 and 5 years in group 2, respectively. The mortality rate is higher in patients who have undergone HD before PD compared without HD history (log rank:<0.001). In the Cox proportional hazards model analysis, preference of PD (RR: 7.72, p<0.001), presence of diabetes (RR: 2.26, p=0.01), pretreatment serum albumin level (RR: 0.37, p<0.001) and catheter exit size infection attacks (RR:0.34, p=0.01) were identified as predictors of mortality. Our data show that mortality in patients transferred to PD from HD was higher than in patients undergoing PD as first-line therapy. Compulsory choice such as vascular access problems and social factors were the most important causes of increasing mortality in patients transferred to PD from HD.
    Nefrologia: publicacion oficial de la Sociedad Espanola Nefrologia 04/2012; 32(3):335-42. · 1.27 Impact Factor
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    ABSTRACT: Vascular calcification is associated with increased cardiovascular mortality in chronic hemodialysis patients. This prospective study investigated the relationship between serum osteoprotegerin, receptor activator of NF-κB ligand, inflammatory markers, and progression of coronary artery calcification score. Seventy-eight hemodialysis patients were enrolled. Serum IL-1β, IL-6, TNF-α, osteoprotegerin, receptor activator of NF-κB, fetuin A, and bone alkaline phosphatase were measured by ELISA. Coronary artery calcification score was measured two times with 1-year intervals, and patients were classified as progressive or nonprogressive. Baseline and first-year serum osteoprotegerin levels were significantly higher in the progressive than nonprogressive group (17.39±9.67 versus 12.90±6.59 pmol/L, P=0.02; 35.17±18.35 versus 24±11.65 pmol/L, P=0.002, respectively). The ratio of serum osteoprotegerin to receptor activator of NF-κB ligand at 1 year was significantly higher in the progressive group (0.26 [0.15-0.46] versus 0.18 [0.12-0.28], P=0.004). Serum osteoprotegerin levels were significantly correlated with coronary artery calcification score at both baseline (r=0.36, P=0.001) and 1 year (r=0.36, P=0.001). Importantly, progression in coronary artery calcification score significantly correlated with change in serum osteoprotegerin levels (r=0.39, P=0.001). In addition, serum receptor activator of NF-κB ligand levels were significantly inversely correlated with coronary artery calcification scores at both baseline (r=-0.29, P=0.01) and 1 year (r=-0.29, P=0.001). In linear regression analysis for predicting coronary artery calcification score progression, only baseline coronary artery calcification score and change in osteoprotegerin were retained as significant factors in the model. Baseline coronary artery calcification score and serum osteoprotegerin levels were significantly associated with progression of coronary artery calcification score in hemodialysis patients.
    Clinical Journal of the American Society of Nephrology 04/2012; 7(6):965-73. · 5.07 Impact Factor
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    ABSTRACT: Recently, stem cells have been used to facilitate healing in animal models of renal failure induced by acute ischemic and nephrotoxic damage. Granulocyte colony-stimulating factor (G-CSF) has been reported to stimulate stem cell mobilization from bone marrow and these cells may contribute to renal repair. In the present study, the effects of G-CSF and stem cell administration as monotherapy or in combination, and the relation of these effects with the duration of therapy, have been investigated in an experimental rat model of carbon tetrachloride (CCl4)-induced nephrotoxicity. The fifty rats included in the study were distributed into 4 main groups, Group 1, 2, 3, and 4, and two subgroups for each group, except for Group 1. All rats received an intraperitoneal injection of CCl4. Then at 6 h, Groups 1, 2a, 3a, and 4a were administered saline, stem cells, G-CSF, and stem cell plus G-CSF, respectively. At 24 h, Groups 2b, 3b, and 4b were administered stem cells, G-CSF, and stem cell plus G-CSF, respectively. All animals were sacrificed 48 h after the CCl4 injections. Serum urea, creatinine, sodium, and potassium levels were measured from blood samples. Tissue α-glutathione S-transferase (GST) levels were also measured from renal tissues. Serum urea was reduced in all groups when compared to Group 1, but the decrease was statistically significant only in Group 3b (P = 0.04). Serum creatinine and sodium levels were similar in all groups (P > 0.05). Tissue GST levels were lower in all groups, but the reduction was significant only in Group 4a, which was administered stem cells + G-CSF at 6 h (P = 0.01). Tubular degeneration and/or tubular dilatation were the most common pathologic changes, and their incidence was similar in all groups (P > 0.05). Although both stem cell and G-CSF monotherapy led to damage reduction, the effect was not significant. However, the reduced damage by the combined use of stem cells and G-CSF, particularly during the early period, was statistically significant.
    Nephro-urology monthly. 01/2012; 4(3):545-50.
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    ABSTRACT: We aimed to investigate whether Olmesartan had an effect on cystatin C levels in hypertensive patients, and evaluate its correlation with blood pressure (BP). Seventy-two patients essential hypertension patients with a known for, at most, the last 3 years were enrolled to the study. Patients were divided in three groups (group 1; receives 20 mg/day olmesartan; group 2, receives 40 mg/day olmesartan; group 3, receives Olmesartan plus hydrochlorothiazide), according to their BP measurements. Blood samples (serum urea, creatinine, sodium, potassium and cystatin C) were collected initially and at the end of the study from all patients and the correlation of these parameters with BP and drug use was investigated. There were no significantly difference between the groups in terms of age, gender, serum urea, creatinine, cystatin C and diastolic BP levels (p > 0.05); while, systolic BP was significantly higher in group 3 at baseline (p = 0.001). After 3 months of olmesartan treatment, the mean serum cystatin C (p: 0.001, 0.023 and 0.018 respectively), systolic (p: 0.001, 0.001 and 0.001 respectively) and diastolic BP levels (p: 0.001, 0.001 and 0.001 respectively) decreased in all groups. However, there was no significant difference in serum creatinine levels (p > 0.05). There were not found correlation between the changes of systolic and diastolic BP and cystatin C levels. Cystatin C is a more sensitive marker to detect of early kidney dysfunction compared to serum creatinine level. Olmesartan treatment led to a decrease of cystatin C level. Therefore, olmesartan can be used to prevent the renal damage in patients with hypertensive and it is independent of drop in blood pressure.
    European review for medical and pharmacological sciences 12/2011; 15(12):1389-94. · 1.09 Impact Factor
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    ABSTRACT: Aim: The aim of this study is to investigate the mortality and the factors which may affect it in patients who were transferred to peritoneal dialysis (PD) from hemodialysis (HD), compared to patients assigned to PD as first-line therapy. Material and Methods: A total of 322 patients treated with PD between 2001 and 2010 were evaluated retrospectively. Twenty three patients were excluded and the data of remaining 299 patients (167F, mean follow up time 38.5±26.8 months, mean age 44.7±15.9 years) were evaluated. Patients were separated into two groups according to their HD history. Group 1 and group 2 consisted of patients with (n=48) and without (n=251) a history of prior HD, respectively. Socio-demographic characteristics such as who helped administer the PD and the preference of patients (compulsory vs their preference) were obtained from the patient records. The clinical data obtained during the last clinical evaluation before the initiation of PD (blood pressure, daily urine volumes, daily ultrafiltration amounts and laboratory parameters) were recorded. Additional systemic diseases and information about the etiologies of the end stage renal disease (ESRD) of all patients were recorded. Frequencies of the infectious complications were recorded. Patient and technique survival were investigated and compared between groups. Results: In group 1, the patients were older and had less urine amounts (p=0.028 and 0.041 respectively). Thirty five patients (70%) and 25 patients (9.3%) have been transferred to PD due to vascular problems in group 1 and 2, respectively (p<0.001). In group 1, 37 (74%) patients were carrying out PD treatment by themselves, compared to 222 (88.4%) patients in group 2 (p=0.016). Incidences of peritonitis and catheter exit site/tunnel infection attacks were found 24.9±26.8 and 27.2±26.5 patient-months in group 1, and 27.4±22.4 and 33.4±24.5 patient-months in group 2, respectively (p=0.50 and 0.12). In group 1, twenty three patients have death and 2 patients have discontinued the treatment due to transplantation. In group 2, 174 patients have discontinued the treatment (55 patients have died, 80 patients have been switched to hemodialysis and 39 patients have received renal transplantation). There were significant differences between groups according to the last condition (p<0.001). Mean patient survival were found 22.9±4.2 and 55.5±2.8 patient-months in group 1 and group 2, respectively. The patient survival rates by Kaplan-Meier analysis were 50%, 40.9%, 27.3% and 9.1% at 1, 2, 3, and 4 years in group 1 and 90.9%, 81.6%, 73.9%, 64.9% and 53.1% at 1, 2, 3, 4 and 5 years in group 2, respectively. The mortality rate is higher in patients who have undergone HD before PD compared without HD history (log rank:<0.001). In the Cox proportional hazards model analysis, preference of PD (RR: 7.72, p<0.001), presence of diabetes (RR: 2.26, p=0.01), pretreatment serum albumin level (RR: 0.37, p<0.001) and catheter exit size infection attacks (RR:0.34, p=0.01) were identified as predictors of mortality. Conclusion: Our data show that mortality in patients transferred to PD from HD was higher than in patients undergoing PD as first-line therapy. Compulsory choice such as vascular access problems and social factors were the most important causes of increasing mortality in patients transferred to PD from HD.
    Nefrologia: publicacion oficial de la Sociedad Espanola Nefrologia 12/2011; 32(3):335-342. · 1.27 Impact Factor
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    ABSTRACT: Hemodialysis patients have extremely increased cardiovascular mortality. Vascular calcification, inflammation, and low serum fetuin-A levels are implicated for increased mortality. In this study, relationship between coronary artery calcification, inflammation, and serum fetuin-A levels were investigated. Seventy-eight hemodialysis patients (38 male, 40 female, mean age: 52±14.5 years) were included. All patients were on dialysis for more than 6 months. Coronary artery calcium scores (CACS) are determined by electron-beam computed tomography. Serum CRP, IL-1β, IL-6, TNF-α, and serum fetuin-A levels were measured. Mean CACS value was 488.5±94.5. Serum fetuin-A levels were negatively correlated with CACS (r:-0.30, P=0.009). Patients are divided into two groups according to total CACS value; group 1 (CACS<10), group 2 (CACS≥10). There was a statistically significance difference in fetuin-A levels between CACS group 1 and group 2 (P=0.001). In this study, serum fetuin-A levels were associated with total CACS. This Fetuin-A may play a role in increased mortality in this group of patients via facilitating CAC.
    Indian Journal of Nephrology 04/2011; 21(2):90-4.
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    ABSTRACT: In this study, we aimed to examine the impact of volume status on blood pressure (BP) and on left ventricular mass index (LVMI) in chronic hemodialysis (HD) patients. This study enrolled 74 patients (F/M: 36/38, mean age 53.5 ± 15.3 years, mean HD time 41.5 ± 41 months) that were on HD treatment for at least 3 months. Demographics, biochemical tests, hemogram and C-reactive protein levels, mean interdialytic weight gain (IDWG), mean percentage of ultrafiltration (UF), and intradialytic complications such as hypotension and cramps were determined. Mean values of predialysis and postdialysis BP measurements were recorded a month before echocardiographic examination. On the day after a midweek dialysis session, 24 h ambulatory BP monitoring (ABPM) and echocardiographic examination were made concurrently. The patients were classified into two groups according to volume status: normovolemic (group 1; 14F/24M, mean age 50 ± 16.7 years, mean dialysis time 47.7 ± 47.7 months) and hypervolemic (group 2; 15F/21M, mean age 57.3 ± 12.7 years, mean dialysis time 34.9 ± 32 months). HD duration, IDWG, UF, and interdialytic complication rates were similar between the two groups (p < 0.05). Eleven patients (28.9%) of group 1 and 8 patients (22.2%) of group 2 showed dipper (p = 0.50). Valvular damage was more common in group 2 (p = 0.002). Whereas 33 patients (91.7%) had left ventricular hypertrophy (LVH) in group 2, 21 patients of the group 1 (55.3%) had LVH (p < 0.001). Although LVMI showed a significant positive correlation with cardiothoracic index, predialysis and postdialysis BP, IDWG, UF, daytime and nighttime BP measurements of 24 h ABPM, a significant negative correlation was seen with Kt/V urea and serum albumin levels. In conclusion, increased IDWG and UF and elevated BP are independent predictors of LVH for HD patients. Increased volume status leads to IDWG and elevated BP and eventually causes severe LVMI increases.
    Renal Failure 01/2011; 33(4):377-81. · 0.94 Impact Factor
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    ABSTRACT: Decreased coronary flow reserve (CFR) is a marker of endothelial dysfunction, coronary artery calcification and inflammation, well-known cardiovascular risk factors in haemodialysis (HD) patients. In this study, we aimed to investigate the correlation of coronary artery calcification scores (CACS) with CFR in HD patients. Sixty-four end-stage renal failure patients were enrolled in this study (38 males, 26 females). Thirty-nine healthy subjects (22 males, 17 females) were included in the control group. Biochemical parameters and acute-phase inflammation marker [high-sensitivity C-reactive protein (hs-CRP)] of patients were recorded before dialysis. The CACS were measured by electron beam computerized tomography method. CFR recordings were performed by trans-thoracic Doppler echocardiography. The relationship between CACS and CFR was evaluated. The mean CACS was 281 +/- 589 and 29 patients had CACS < 10. Patients with CACS > 10 had significantly lower CFR values compared to patients with CACS < 10 (1.56 +/- 0.38 vs 1.84 +/- 0.53, P = 0.024). However, there was no difference in hs-CRP values between the groups. CFR was negatively correlated with CACS (r = -0.276, P = 0.030). In multiple stepwise regression analysis, CACS was found to be an independent variable for predicting CFR (P = 0.048). During a follow-up of 18 months, 10 patients had experience of cardiovascular events. Patients with CACS > 10 had significantly higher event rate [34.5% (10/29) vs 0% (0/24)] compared to those with CACS < 10 (P = 0.001). Patients who developed cardiovascular events had significantly higher mean CACS and lower CFR values than the remaining group (P = 0.019 and P = 0.039). All of four patients who died during follow-up were in the CFR < 2 and CACS > 10 groups. CACS was associated with CFR in HD patients. However, we did not find any association of inflammation with CACS and CFR. This association between CFR and CACS might indicate two different (anatomical and functional) aspects of the common pathophysiology of the arterial system in HD patients.
    Nephrology Dialysis Transplantation 02/2010; 25(8):2685-90. · 3.37 Impact Factor

Publication Stats

53 Citations
27.05 Total Impact Points

Institutions

  • 2014
    • Sisli Etfal Training and Research Hospital
      İstanbul, Istanbul, Turkey
  • 2010–2012
    • Istanbul University
      • • Department of Family Medicine (Istanbul Medical Faculty)
      • • Department of Nephrology
      İstanbul, Istanbul, Turkey