Elif Ari

The Correlation of Serum Trace Elements and Heavy Metals with Carotid Artery Atherosclerosis in Maintenance Hemodialysis Patients

Changes in essential trace elements and heavy metals may affect the atherosclerotic state of patients on maintenance hemodialysis (HD). The aim of the study was to evaluate the relation between the serum levels of some trace elements and heavy metals (iron, zinc, manganese, copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio) and carotid artery intima–media thickness (CIMT) in HD patients. Fifty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. The serum levels of trace elements (iron, zinc, manganese, copper, and magnesium) and heavy metals (cobalt, cadmium, and lead) were measured by Atomic Adsorption Spectrophotometer (UNICAM-929). CIMT was assessed by carotid artery ultrasonography. The serum levels of iron, zinc, and manganese were lower; levels of copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio were higher in HD patients compared to controls. CIMT in HD patients were higher than the control group (0.64 ± 0.11 vs 0.42 ± 0.05, p < 0.001). There was a significant negative correlation between CIMT and serum levels of zinc (r = −0.70, p < 0.01), iron (r = −0.71, p < 0.01), and manganese (r = −0.47, p < 0.01), while there was a significant positive correlation between CIMT and serum levels of copper (r = 0.63, p < 0.01), magnesium (r = 0.77, p < 0.01), cobalt (r = 0.63, p < 0.01), cadmium (r = 0.48, p < 0.01), lead (r = 0.38, p < 0.01), and copper/zinc ratio (r = 0.68, p < 0.01). A linear regression analysis showed that serum levels of magnesium, cadmium, lead, and copper/zinc ratio were still significantly and positively correlated with CIMT. We propose that copper/zinc ratio, magnesium and toxic metals cadmium and lead are independent determinants of CIMT in maintenance HD patients without known atherosclerotic disease.

Oxidative DNA damage correlates with carotid artery atherosclerosis in hemodialysis patients.

Oxidative stress is accepted as a nonclassical cardiovascular risk factor in chronic renal failure patients. The aim of this study was to evaluate the relation between oxidative DNA damage (8‐hydroxy‐2′‐deoxyguanosine/deoxyguanosine [8‐OHdG/dG] ratio), oxidative stress biomarkers, antioxidant enzymes, and carotid artery intima‐media thickness (CIMT) in hemodialysis (HD) patients. Forty chronic HD patients without known atherosclerotic disease and 48 age‐ and sex‐matched healthy individuals were included in the study. Plasma malondialdehyde (MDA) levels and 8‐OHdG/dG ratio were determined as oxidative stress markers. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured as antioxidants. CIMT was assessed by carotid artery ultrasonography. 8‐OHdG/dG ratios and MDA levels were higher; SOD and GPx activities were lower in HD patients compared to controls. HD patients had significantly higher CIMT compared to controls (0.61 ± 0.08 vs. 0.42 ± 0.05, p < 0.001). There was a significant positive correlation between CIMT and 8‐OHdG/dG ratio (r = 0.57, p < 0.01) and MDA levels (r = 0.41, p < 0.01), while there was a significant negative correlation between CIMT and SOD (r = −0.47, p < 0.01) and GPx levels (r = −0.62, p < 0.01). It is firstly demonstrated that CIMT is positively correlated with oxidative DNA damage in HD patients without known atherosclerotic disease.

Unusual causes of peritonitis in a peritoneal dialysis patient: Alcaligenes faecalis and Pantoea agglomerans

An 87 -year-old female who was undergoing peritoneal dialysis presented with peritonitis caused by Alcaligenes faecalis and Pantoea agglomerans in consecutive years. With the following report we discuss the importance of these unusual microorganisms in peritoneal dialysis patients.

Evaluation of Sepsis/Systemic Inflammatory Response Syndrome, Acute Kidney Injury, and RIFLE Criteria in Two Tertiary Hospital Intensive Care Units in Turkey

Sepsis is a common cause of acute renal failure in intensive care units (ICU) with mortality rates as high as 60%. In this study, the clinical and laboratory predictors of acute kidney injury (AKI) in critically ill Turkish patients with sepsis/systemic inflammatory response syndrome were identified. We studied 139 (67 females/72 males) patients admitted to our ICUs with sepsis/systemic inflammatory response syndrome without renal failure. The clinical and laboratory parameters and treatments were recorded. Patients were classified as those without AKI (n = 60; 43.20%) and those with AKI (n = 79; 56.80%) based on the RIFLE (Risk, Injury, Failure, Loss, End-stage renal disease) criteria. Those with AKI were further classified as: risk in 27 (19%), injury in 25 (17.9%), failure in 25 (17.9%), and loss in 2 (1.4%). We found that the mortality rate increased with the severity of renal involvement: 56% in risk, 68% in injury, 72% in failure, and 100% in loss categories. Patients with AKI had a more positive fluid balance, higher central venous pressure, more vasopressor use, and lower systolic blood pressure. In multivariate analysis, the sequential organ failure assessment score, blood pressure, serum creatinine, and fluid balance were risk factors for the development of AKI. In this population, the incidence of AKI was higher and contrary to previous knowledge. A positive fluid balance also carries a risk for AKI and mortality in septic ICU patients. The RIFLE criteria were found to be applicable to our ICU population.

Epicardial fat thickness is associated with impaired coronary flow reserve in hemodialysis patients

Cardiovascular disease (CVD) is the main cause of mortality in hemodialysis (HD) patients. Epicardial fat tissue (EFT) is a new risk factor in CVD. The aim of this study was to evaluate the association between EFT and coronary artery flow reserve (CFR), which is an early indicator of endothelial dysfunction in coronary vessels of HD patients. We performed a cross‐sectional study including 71 chronic HD patients and 65 age‐ and sex‐matched healthy controls. Epicardial fat tissue was significantly higher in HD patients when compared to healthy controls (6.53 ± 1.01 mm vs. 5.79 ± 1.06 mm, respectively, P < 0.001). On transthoracic Doppler echocardiography, CFR values were significantly lower in HD patients when compared to healthy controls (1.73 ± 0.11 vs. 2.32 ± 0.28, P < 0.001). Correlation analysis showed CFR values to be inversely correlated with EFT (r = −0.287, P < 0.05). Multiple linear regression analysis was used to define independent determinants of EFT in HD patients. Artery flow reserve, age, body mass index and total cholesterol levels were independently correlated with EFT thickness. This study demonstrated that EFT was significantly higher among HD patients compared to healthy controls. In addition, this study was the first to demonstrate an inverse correlation between EFT and CFR in this patient population.

Protective effect of the vasopressin agonist terlipressin in a rat model of contrast-induced nephropathy.

Background/Aims: Contrast-induced nephropathy (CIN) remains a leading cause of iatrogenic acute renal failure. Terlipressin, a long-acting analog of vasopressin, may improve renal function. This study aimed to investigate the possible protective effect of terlipressin against the development of experimental CIN in rats. Methods: Wistar albino rats (n = 32) were allocated randomly into four equal groups of 8 each, i.e. control, terlipressin, contrast media (CM), and terlipressin plus contrast media (TCM). CIN was induced by intravenous administration of indomethacin (10 mg/kg), N-nitro L-arginine methyl ester (L-NAME, 10 mg/kg, twice at 15 and 30 min), and high-osmolar contrast media meglumine amidotrizoate 60%. Renal function parameters, kidney histology, and tubular expression of vascular endothelial growth factor (VEGF) were determined. Results: Mean serum creatinine levels were decreased (p < 0.05) and creatinine clearance (p < 0.05) increased in the TCM group compared with the CM group. Notably, rats in the TCM group displayed less tubular necrosis (p < 0.05), medullary congestion (p < 0.05), and a reduced tubular expression of VEGF (p < 0.05) compared with the CM group. Conclusion: These results demonstrate that terlipressin can inhibit the development of CIN.

Streptococcus bovis bacteremia related to colon adenoma in a chronic hemodialysis patient.

We report the case of a 54‐year‐old hemodialysis patient who presented with recurrent fever due to Streptococcus bovis bacteremia related to colonic tubulovillous adenoma. Following polypectomy and broad‐spectrum antibiotic therapy, the patient totally recovered. In this paper, we discussed the relation between S. bovis bacteremia, colonic adenomas, and hemodialysis. Awareness of this association is critical for early diagnosis and management.

Epicardial fat tissue thickness is correlated with diminished levels of co-enzyme Q10, a major antioxidant molecule among hemodialysis patients

OBJECTIVES Accelerated atherosclerosis is the major cause of mortality in patients on chronic maintenance hemodialysis (HD). Epicardial fat tissue (EFT) is a new risk factor in cardiovascular disease (CVD). The aim of this study was to evaluate the relation between plasma coenzyme Q10 levels (Co-Q10) which is a potent physiologic antioxidant and EFT thickness in HD patients. DESIGN AND METHODS Seventy one chronic HD patients and 65 age and sex matched healthy individuals were included in the study. Plasma Co-Q10 levels were performed by high-performance liquid chromatography (HPLC) measurements. EFT was measured by transthoracic echocardiograpy (TTE) performed with a VIVID 7 instrument. RESULTS Plasma Co-Q10 levels (1.36±0.43 vs 2.53±0.55, p<0.001) were significantly lower in HD patients compared to controls. EFT was significantly increased in HD patients compared to healthy controls (6.53±1.01 vs. 5.79±1.06 mm respectively, p<0.001). Correlation analysis showed that plasma Co-Q10 levels were inversely correlated with EFT (r=-0.263, p<0.05). Multiple linear regression analysis was used to define independent determinants of EFT in HD patients. According to linear regression analysis, age, BMI, total cholesterol and Co-Q10 levels were found to be independent predictors of EFT (adjusted r(2)=0.38, p<0.001). CONCLUSION This study demonstrated that EFT thickness was significantly higher among HD patients compared to healthy controls. In addition; this study was the first to demonstrate an inverse correlation between EFT thickness and Co-Q10 levels in this patient population.

Serum coenzyme Q10 levels are associated with coronary flow reserve in hemodialysis patients

Accelerated atherosclerosis is the major cause of mortality in patients on chronic hemodialysis (HD). The aim of this study was to evaluate the relation between coenzyme Q10 (CoQ10) levels and coronary flow reserve (CFR) in HD patients as an indicator of atherosclerosis. Seventy‐one chronic HD patients and 65 age‐ and sex‐matched healthy individuals were included in the study. Plasma CoQ10 levels were performed by high‐performance liquid chromatography measurements. CFR was assessed by transthoracic Doppler echocardiography. Serum CoQ10 levels (1.36 ± 0.43 vs. 2.53 ± 0.55, P < 0.001) and CFR values (1.73 ± 0.11 vs. 2.32 ± 0.28, P < 0.001) were significantly lower in HD patients compared with controls. There was a significant positive correlation between CFR and serum levels of CoQ10 (r = 0.669, P < 0.001). A linear regression analysis showed that serum levels of CoQ10 were still significantly and positively correlated with CFR (regression coefficient = 0.235, P < 0.001). Our data have demonstrated that HD patients exhibit decreased plasma CoQ10 levels and CFR values. The study also showed for the first time that serum CoQ10 levels independently predict CFR in HD patients.

Pleiotropic and Renoprotective Effects of Erythropoietin Beta on Experimental Diabetic Nephropathy Model

Background: This study aimed at investigating the possible protective effect of erythropoietin beta on experimental diabetic nephropathy (DN) model in rats. Methods: Sprague Dawley rats (n = 32) were allocated into 4 equal groups of 8 each, the control (Group C), diabetes (Group D), erythropoietin beta (Group E), and erythropoietin beta treated DN (Group E + D) groups. Streptozocin (65 mg/kg) was used to induce diabetes in 10-week old rats. Erythropoietin beta was given intraperitoneally at a dose of 500 IU/kg/3 days of a week for 12 weeks. Renal function parameters, intrarenal levels and activities of oxidative stress biomarkers, serum inflammatory parameters and kidney histology were determined. Results: Group E + D had lower mean albumin-to-creatinine ratio (p < 0.001) as well as higher creatinine clearance (p = 0.035) than the diabetic rats (Group D). Intrarenal malondialdehyde levels were significantly lower (p = 0.004); glutathione (GSH) levels (p = 0.003), GSH peroxidase (p = 0.004) and superoxide dismutase (p < 0.005) activities of renal tissue were significantly higher in Group E + D than in Group D. The mean serum levels of interleukin-4 (p < 0.005), interleukin 1 beta (p = 0.012), interferon gamma (p = 0.018) and tumor necrosis factor alpha (p < 0.005) were significantly lower; serum levels of monocyte chemoattractant protein 1 (p = 0.018) was significantly higher in Group E + D when compared to Group D. The mean scores of tubulointerstitial inflammation (p = 0.004), tubular injury (p = 0.013) and interstitial fibrosis (p = 0.003) were also lower in Group E + D when compared to Group D. Conclusion: Our data seem to suggest a potential role of erythropoietin beta for reducing the progression of DN in an experimental rat model. This protective effect is, in part, attributable to the suppression of the inflammatory response and oxidative damage.