Dingwei Kuang

The ratio of CRP to prealbumin levels predict mortality in patients with hospital-acquired acute kidney injury

BackgroundAnimal and human studies suggest that inflammation and malnutrition are common in acute kidney injury (AKI) patients. However, only a few studies reported CRP, a marker of inflammation, albumin, prealbumin and cholesterol, markers of nutritional status were associated with the prognosis of AKI patients. No study examined whether the combination of inflammatory and nutritional markers could predict the mortality of AKI patients.Methods155 patients with hospital-acquired AKI were recruited to this prospective cohort study according to RIFLE (Risk, Injury, Failure, Lost or End Stage Kidney) criteria. C-reactive protein (CRP), and the nutritional markers (albumin, prealbumin and cholesterol) measured at nephrology consultation were analyzed in relation to all cause mortality of these patients. In addition, CRP and prealbumin were also measured in healthy controls (n = 45), maintenance hemodialysis (n = 70) and peritoneal dialysis patients (n = 50) and then compared with AKI patients.ResultsCompared with healthy controls and end-stage renal disease patients on maintenance hemodialysis or peritoneal dialysis, patients with AKI had significantly higher levels of CRP/prealbumin (p < 0.001). Higher level of serum CRP and lower levels of albumin, prealbumin and cholesterol were found to be significant in the patients with AKI who died within 28 days than those who survived >28 days. Similarly, the combined factors including the ratio of CRP to albumin (CRP/albumin), CRP/prealbumin and CRP/cholesterol were also significantly higher in the former group (p < 0.001 for all). Multivariate analysis (Cox regression) revealed that CRP/prealbumin was independently associated with mortality after adjustment for age, gender, sepsis and sequential organ failure assessment (SOFA, p = 0.027) while the others (CRP, albumin, prealbumin, cholesterol, CRP/albumin and CRP/cholesterol) became non-significantly associated. The hazard ratio was 1.00 (reference), 1.85, 2.25 and 3.89 for CRP/prealbumin increasing according to quartiles (p = 0.01 for the trend).ConclusionsInflammation and malnutrition were common in patients with AKI. Higher level of the ratio of CRP to prealbumin was associated with mortality of AKI patients independent of the severity of illness and it may be a valuable addition to SOFA score to independent of the severity of illness and it may be a valuable addition to SOFA score to predict the prognosis of AKI patients.

Nitrotyrosine Level Was Associated with Mortality in Patients with Acute Kidney Injury

Background To examine the characteristics of oxidative stress in patients with acute kidney injury (AKI) and investigate the association between plasma nitrotyrosine levels and 90-day mortality in patients with AKI. Methodology/Principal Findings 158 patients with hospital-acquired AKI were recruited to this prospective cohort study according to RIFLE (Risk, Injury, Failure, Lost or End Stage Kidney) criteria. Twelve critically ill patients without AKI and 15 age and gender-matched healthy subjects served as control. Plasma 3-nitrotyrosine was analyzed in relation to 90-day all cause mortality of patients with AKI. The patients with AKI were followed up for 90 days and grouped according to median plasma 3-nitrotyrosine concentrations. Highest 3-NT/Tyr was detected in patients with AKI compared with healthy subjects, and critically ill patients without AKI (ANOVA p<0.001). The 90-day survival curves of patients with high 3-NT/Tyr showed significant differences compared with the curves of individuals with low 3-NT/Tyr (p = 0.001 by log rank test). Multivariate analysis (Cox regression) revealed that 3-NT/Tyr (p = 0.025) was independently associated with mortality after adjustment for age, gender, sepsis and Acute Physiology and Chronic Health Evaluation (APACHE) II score. Conclusions/Significance There is excess plasma protein oxidation in patients with AKI, as evidenced by increased nitrotyrosine content. 3-NT/Tyr level was associated with mortality of AKI patients independent of the severity of illness.

Risk factors associated with brachial–ankle pulse wave velocity among peritoneal dialysis patients in Macao

BackgroundCardiovascular disease is the leading cause of mortality among peritoneal dialysis (PD) patients in Macao. Increased arterial stiffness determined by pulse wave velocity (PWV) has been established as an independent predictor of cardiovascular mortality in end-stage renal disease patients. The present study aims to investigate the relationship between arterial stiffness and its associated risk factors in chronic PD patients.MethodsA total of 96 chronic PD patients (48 males/48 females) were included in the cross-sectional study. Arterial stiffness was assessed by brachial-ankle PWV (baPWV). Patients were divided into two subgroups according to mean baPWV value. On enrollment, clinical characteristics and biochemical parameters were collected.ResultsCompared with low baPWV group patients, high baPWV group patients were significant older (p<0.001) and more likely to have a high proportion of female gender (p=0.004) as well as previous CVD history (p=0.008). Serum albumin, pre-albumin levels and residual renal creatinine clearance (CCr) were significantly lower but the serum ferritin level was significantly higher in high baPWV group patients than in low baPWV group patients (all p<0.01). BaPWV was positively associated with age (r=0.534, p<0.001), Charlson comorbidity index (r=0.350, p<0.001) and serum ferritin level (r=0.340, p=0.001). Meanwhile, baPWV negatively correlated with serum albumin (r=−0.479, p<0.001), pre-albumin levels (r=−0.320, p=0.003) and residual renal CCr (r=−0.177, p=0.048). Age-adjusted partial correlation test found a significant correlation between baPWV and CRP (r=0.462, p<0.001). Multivariate regression analysis showed that baPWV was independently associated with age (p<0.001), serum albumin level (p=0.015), CRP (p=0.019) and residual renal CCr (p=0.045).ConclusionArterial stiffness, assessed by baPWV, had an independent correlation with age, serum albumin level, CRP level and residual renal CCr among PD patients in Macao.

Intima-Media Thickness of the Carotid Artery and Its Correlation Factors in Maintenance Hemodialysis Patients: A Cross-Sectional Study

Background: To investigate the relationship between the intima-media thickness of the carotid artery (CA-IMT) and its major risk factors in maintenance hemodialysis (MHD) patients. Methods: Seventy-five MHD patients and 30 healthy volunteers were enrolled. The MHD patients were divided into 3 subgroups according to their CA-IMT value. Results: CA-IMT values in the MHD group were significantly higher than those in the control group. The differences in age, systolic blood pressure (SBP), and levels of serum albumin, prealbumin, cholesterol and serum phosphate between the increased IMT group and the normal IMT group were significant. SBP and serum phosphate levels were also greater in the abnormal IMT group than those in the normal IMT group. Significant relationships were found between CA-IMT and age, SBP, and serum levels of phosphate, albumin and prealbumin. In multiple regression analysis, a high serum phosphate level, low serum prealbumin level and high SBP were significant independent risk factors of increased CA-IMT. Conclusions: CA-IMT was increased dramatically in MHD patients. A high serum phosphate level, low serum prealbumin level and high SBP may be associated with advanced arteriosclerosis.

Efficacy of Cytokine Removal by Plasmadiafiltration Using a Selective Plasma Separator: In Vitro Sepsis Model

More effective removal of pro‐ and anti‐inflammatory cytokines may play an important role in the treatment of sepsis. Plasmadiafiltration (PDF) with a larger selective plasma separator was performed to study the cytokine and plasma protein permeability profiles of the membrane in an in vitro sepsis model. The in vitro sepsis model was constructed by exposure of human whole blood to bacterial lipopolysaccharide. EVACURE 2A, a selective plasma separator, was placed in the blood circuit of PDF. Sieving coefficients of cytokines and plasma protein were tested in post‐dilution PDF mode at the following operating parameters: blood flow rate 150 mL/min; dialysate flow rate 33.33 mL/min; replacing fluid flow rate 6.67 mL/min; ultrafiltration rate 5 mL/min. An enzyme linked immunoadsorbent assay was used to measure the concentrations of tumor necrosis factor‐α (TNF‐α), high‐mobility group box 1 protein (HMGB1), interleukin‐1β (IL‐1β), interleukin‐1 receptor antagonist (IL‐1ra), interleukin‐2 (IL‐2), interleukin‐2 receptor (IL‐2r), interleukin‐6 (IL‐6), interleukin‐8 (IL‐8), interleukin‐10 (IL‐10) in plasma and ultrafiltrate. Sieving coefficients of different solutes ranged from 0.1 to 1.0 at first, decreased 10%–60% after 1 h of PDF, and then remained stable. Total clearance rates of cytokines ranged from 15 to 80 mL/min. The concentrations of cytokines decreased 20–80% after 1 hour of PDF. The sieving coefficient of albumin was 0.1 at first and then decreased to 0.05 after 1 hour of therapy. Plasmadiafiltration with Evacure 2A plasma separator can effectively remove almost all of the inflammatory mediators with low albumin loss.

Prevalence and risk factors associated with peripheral artery disease in elderly patients undergoing peritoneal dialysis.

Background Rapid growth of the elderly peritoneal dialysis (PD) population is posing a special challenge for renal teams. Peripheral artery disease (PAD) has been reported to be an independent predictor of cardiovascular and all-cause mortality in hemodialysis patients. However, the prevalence and associated risk factors for PAD in elderly PD patients have not yet been fully investigated. Methods A total of 69 elderly PD patients were included in the present study. PAD was defined as either an ankle-brachial index < 0.9 or a history of intermittent claudication, lower-limb amputation, foot ulcers, or gangrene. On enrollment, clinical and biochemical characteristics were collected. Results The overall prevalence of PAD was 31.9%. Compared with non-PAD patients, PAD patients were significantly older and more likely to be female and have longer PD duration and lower diastolic blood pressure (P < 0.001, = 0.002, 0.018, and 0.007, respectively). Serum albumin level (P < 0.001) and residual renal Kt/V value (P < 0.001) were significantly lower, but the serum C-reactive protein level (P = 0.005) was significantly higher, in PAD patients compared with non-PAD patients. Logistic regression analysis showed that serum albumin level (odds ratio = 1.485, P = 0.040) and residual renal Kt/V value (odds ratio = 1.725, P = 0.016) were independently associated with PAD. Conclusion A high prevalence of PAD appeared among elderly PD patients in Macao. Serum albumin level and residual renal Kt/V value were independently related to PAD.

Effectiveness of Sodium Hypochlorite in the Prevention of Catheter Related Infections

Vascular access in hemodialysis is a major point of concern in the management of chronic patients. Although arteriovenous fistula remains as the access of first choice, tunneled central venous catheters are still commonly used. Infection remains the principal cause of catheter dysfunction or loss. Many protocols have been used in order to prevent exit site infections and bacteremia. We describe our experience with the use of sodium hypochlorite, an electrolytic chloroxidizer used as a topical disinfectant. It has been shown to be active against a broad spectrum of potential pathogens and has other specific advantages compared to other cleansing agents, including its non-toxic, non-irritating nature and its low cost. We conclude that sodium hypochlorite solution in different concentrations (10 and 50%) is effective in preventing exit site infections and bacteremia associated with tunneled central venous catheters in chronic hemodialysis patients.

Risk Factors of Arterial Damage Assessed by ABI and baPWV among Hemodialysis Patients in Macau

Cardiovascular disease (CVD) is the leading cause of mortality and morbidity among patients with ESRD on chronic dialysis. Arterial damage is one of the characteristics of CVD. But the association between arterial damage and conventional risk factors for CVD has not yet been fully highlighted in chronic hemodialysis patients. Here we validate the clinical value of assessment of arterial damage by ABI and PWV in chronic hemodialysis patients in Macau.