Metastatic spondylodiscitis in central venous catheter related bloodstream infections in hemodialysis patients: Risk factors and prognosis.

BACKGROUND: Infection is one of the most common causes of death in hemodialysis patients. Catheter infections are among the most common infections in this patient group. Spondylodiscitis which has a high incidence in ESRD is more commonly encountered in patients with CVCs compared to AVF. In this study, we aimed to evaluate the frequency and risk factors of spondylodiscitis in catheter-related bloodstream infections in hemodialysis patients. METHODS: In total, 1620 patients were screened and 42 male and 35 female patients with central catheter infection with a mean age of 65.8 ± 14.9 years were included in this study. Patients with metastatic infections secondary to CVC related bloodstream infections were determined. The diagnosis of spondylodiscitis was based on clinical information, computed tomography (CT) and magnetic resonance imaging (MRI), and vertebral cultures. RESULTS: Metastatic infection due to catheter infection was observed in 15 patients (19.5%). In the regression analysis, CRP level and RRT time were found to be significantly correlated with the development of metastatic infection. Spondylodiscitis was the most common subtype of metastatic infections (8/15). The presence of lumbar hernia was associated with increased risk of metastatic spondylodiscitis in case of catheter infection in hemodialysis patients. The only factor associated with resistance to medical treatment was the time from admission to diagnosis. CONCLUSION: Patients with long RRT time and high blood CRP levels on admission should be closely monitored for metastatic infection in patients with CVC related bloodstream infections. Screening for spondylodiscitis with CT or MRI should be performed in patients with symptoms, since early diagnosis may prevent the development of possible neurological deficits and treatment resistance.

Association between osteoprotegerin, fetuin-A, carotid intima media thickness, and urinary albumin excretion in Type 2 diabetes.

AIMS: Vascular calcification and atherosclerosis play a vital role in the development of cardiovascular morbidity and mortality in diabetic patients, especially when complications of diabetic nephropathy occur. Osteoprotegerin (OPG) and fetuin-A are two markers of vascular calcification. We evaluated the association between these vascular markers and urinary albumin excretion in diabetic patients. METHOD: Three groups were arranged containing 40 patients: normoalbuminuric (Group 1), microalbuminuric (Group 2), and macroalbuminuric (Group 3). In addition to the obtained data, levels of hs-CRP (high sensitivity-CRP) and homocysteine were examined. RESULTS: OPG levels of patients in Group 2 were higher than in Group 1 (p = 0.058). OPG levels in Group 3 were lower than in Groups 1 or 2 (p = 0.014 and 0.000, respectively). Levels of fetuin-A in Group 2 were determined to be lower than in Groups 1 and 3 (p = 0.001 and 0.000, respectively). Carotid intima media thickness (CIMT) in Group 3 was higher than in Group 1 (p = 0.002). CIMT in Group 2 was also higher than in Group 1 (p = 0.039). A positive correlation between fetuin-A and OPG was found (p = 0.012, r = 0.393). Additionally, a positive correlation between hs-CRP and fetuin-A in Group 2 (p = 0.020, r = 0.367) and a negative correlation between hs-CRP and OPG in Group 3 (p = 0.036, r = -0.333) were observed. CONCLUSIONS: The differences found between albuminuria and OPG or fetuin-A may be due to the different doses and variety of medications the patients received, in addition to genetic and racial factors. So far, in our country, polymorphisms related to OPG and fetuin-A have not been defined. Further detailed studies about polymorphisms will have additional value.

The effects of iron on FGF23-mediated Ca-P metabolism in CKD patients.

BACKGROUND: Fibroblast growth factor 23 (FGF23) is an important counterregulatory hormone for phosphate homeostasis. Since it has been reported that iron administration induces hypophosphatemic osteomalacia by triggering FGF23 synthesis, we hypothesized that iron administration might lead to a further increase in FGF23, resulting in alterations to Ca-P metabolism in a stage 5 CKD population. METHODS: This cross-sectional study was performed in a single center, and involved 73 hemodialysis patients (47.7 ± 15.74 years old, 68.5% men), 29 peritoneal dialysis patients (44.55 ± 15.05 years old, 62.1% men), and 55 healthy (43.57 ± 14.36 years old, 55.6% men) subjects. The dialysis group was subcategorized according to iron therapy administration into users and nonusers. RESULTS: The median iFGF23 level was significantly higher in the dialysis population than in the healthy controls [88.050 (25.2-1038.3) pg/ml versus 46.95 (2.4-356) pg/ml (p < 0.001)]. In the dialysis population, a significantly lower median iFGF23 level was observed in iron therapy users than in nonusers [87.6 (25.2-1038.3) versus 119 (51.6-1031); respectively, p = 0.045]. A significant negative association between iron administration and iFGF23 level was revealed by both univariate (r = -0.237, p = 0.016) and multivariate (ß = -0.221, p = 0.032) analysis. No association was found between iFGF23 and serum ferritin and iron levels. Also, there was no association between iron therapy and serum phosphate level. CONCLUSION: In contrast to what is seen for the general population, this study showed that there was a negative relationship between iron administration and serum iFGF23 level in a dialysis population. We can therefore conclude that if high levels of FGF23 are harmful, iron therapy may have a beneficial effect on bone metabolism by reducing FGF23 levels in a dialysis population.

Protective effect of beta-glucan on contrast induced-nephropathy and a comparison of beta-glucan with nebivolol and N-acetylcysteine in rats.

BACKGROUND: It has been shown that beta-glucan (BG), which has antioxidant and immunomodulatory effects, attenuats renal ischemia-reperfusion injury. We aimed to investigate whether BG might have a preventive role against the development of contrast-induced nephropathy and to compare its effect with nebivolol (Nb) and N-acetylcysteine (NAC). METHODS: Thirty-six Wistar albino female rats were randomly divided into six groups (n = 6 each): control, contrast media (CM), BG, BG + CM, Nb + CM, and NAC + CM. With the exception of control and CM groups, the others were given drugs orally once a day for 5 days. Kidney function parameters, inflammatory parameters, and serum and renal tissue oxidative stress markers were measured. RESULTS: Increases of serum creatinine and blood urea nitrogen levels were significantly higher (p < 0.05) in the CM group only. Absolute changes of serum creatinine levels in BG, BG + CM and Nb + CM groups were significantly lower than those in the CM group (p < 0.05). Serum levels of advanced oxidation protein products and malondialdehyde were significantly less (p < 0.05) in the BG group compared to the CM group. Histopathological lesions in the CM group were more advanced (p < 0.05). No significant differences between the BG + CM, Nb + CM and NAC + CM groups were found with regard to histopathological findings. CONCLUSION: This study suggests that BG protects or ameliorates against contrast-induced nephropathy. Its beneficial effects may be similar to or greater than those of Nb or NAC.

Effects of everolimus on cytokines, oxidative stress, and renal histology in ischemia-reperfusion injury of the kidney.

BACKGROUND: To evaluate the effects of everolimus on renal ischemia-reperfusion injury (IRI). METHODS: Wistar albino rats were divided into control, ischemia-reperfusion (IR), and ischemia-reperfusion/everolimus (IR/eve) groups. Everolimus was administered for seven consecutive days to the IR/eve group prior to injury. IR and IR/eve groups underwent forty-five minutes ischemia followed by the application of reperfusion at 2 and 24 hours. Blood samples and kidneys were taken from all animals. RESULTS: . Serum blood urea nitrogen and creatinine levels increased at two hours of reperfusion in the IR and IR/eve groups, and decreased at 24 hours of reperfusion in the IR group. In the IR/eve group, we detected significantly high interleukin-6 levels and low tumor necrosis factor-alpha and malondialdehyde levels at 24 hours. Myeloperoxidase levels increased at two hours of reperfusion in the IR/eve group, but decreased significantly at 24 hours. Everolimus did not improve renal tubular and interstitial injuries in renal IRI. CONCLUSIONS: It has been demonstrated that pretreatment with everolimus has beneficial effects on cytokines and oxidative stress in renal IRI. However, these effects are insufficient for the correction of histopathological changes and restoration of normal kidney function.