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BACKGROUND: Hypertension is one of the most critical risk factors for cardiovascular disease, which is the leading cause of death in hemodialysis (HD) patients. Medium cut-off (MCO) membrane increases the clearance of medium molecules, which could improve blood pressure (BP) control. This study aimed to compare the effect of MCO and high-flux hemodialysis membranes on BP assessed by ambulatory blood pressure monitoring (ABPM). METHODS: This is a pre-established secondary analysis of a 28-week, randomized, open-label crossover clinical trial. Patients were randomized to HD with MCO or high-flux membranes over 12 weeks, followed by a 4-week washout period, and then switched to the alternate membrane treatment for 12 weeks. ABPM was started before the HD session and ended at least 24 h later in weeks 1, 12, 16, and 28. RESULTS: 32 patients, 59% male, with a mean age of 52.7 years, and 40% with unknown CKD etiology, were enrolled. The dialysis vintage was 8 years, and more than 70% of the patients had hypertension. Regarding 24-h BP control, morning diastolic BP showed an increase in the high-flux compared to stability in the MCO group (interaction effect, p = 0.039). The adjusted ANOVA models showed no significant difference in the morning BP levels between the groups. Considering only the period of the HD session, patients in the MCO, compared to those in the high-flux membrane group, showed greater BP stability during dialysis, characterized by smaller variation in the pre-post HD systolic and minimum systolic BP (treatment effect, p = 0.039, and p = 0.023, respectively). CONCLUSIONS: MCO membrane seems to have a beneficial effect on morning BP and favors better BP stability during HD sessions.
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Monitoreo Ambulatorio de la Presión Arterial , Cefalosporinas , Hipertensión , Humanos , Masculino , Persona de Mediana Edad , Femenino , Presión Sanguínea , Diálisis Renal/efectos adversos , Hipertensión/diagnóstico , Hipertensión/etiologíaRESUMEN
Introduction: The interaction between blood and dialysis membrane increases the risk of clot formation. Membrane properties can interfere with coagulation activation during dialysis. Heparin is usually used to ensure anticoagulation, which can be monitored by the Activated Clotting Time (ACT) test. The purpose of this study was to compare the ACT of patients with chronic kidney disease (CKD) undergoing hemodialysis with high-flux (HF) and medium cut-off (MCO) membranes. Methods: This is a prospective, randomized, crossover study in which 32 CKD patients were dialyzed for 12 weeks with each membrane. Blood clotting measured by ACT was evaluated at the beginning, 2nd, and 4th hour of the dialysis session. Throughout the study, there were no changes in the dose or administration method of heparin. Results: Patients mainly were middle-aged, non-black males on hemodialysis for eight years. Before randomization, ACT values were 132 ± 56, 195 ± 60, and 128 ± 32 seconds at pre-heparinization, 2nd and 4th hour, respectively. After 12 weeks, ACT values in HF and MCO groups were 129 ± 17, 205 ± 65 and 139 ± 38 seconds, and 143 ± 54, 219 ± 68 and 142 ± 45 seconds, respectively. An ANOVA model adjusted and unadjusted for repeated measures showed a significant time but no treatment or interaction effects. In an additional paired-sample analysis, no difference between ACT values of HF and MCO Groups was observed. Discussion and Conclusion: There was no difference regarding the ACT test during dialysis therapy using HF or MCO membranes. This data suggests that no adjustment in the dose or administration method of heparin is necessary with the use of MCO dialysis membranes.
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OBJECTIVES: Chronic kidney disease (CKD) patients on hemodialysis may have a modified appetite due to several factors including a lack of uremic toxins elimination. The use of medium cutoff (MCO) dialysis membranes has been suggested as an alternative to improve the removal of toxins, especially those of medium and high molecular weight. This study aimed to compare the effect of hemodialysis using MCO and high-flux membranes on the appetite and leptin levels of CKD patients. DESIGN AND METHODS: This is a predefined exploratory analysis of a randomized, open study, with a crossover design of 28 weeks of follow-up, which compared the effects of MCO and high-flux membranes in 32 CKD patients on hemodialysis. Appetite assessments were performed using the Appetite and Food Satisfaction Questionnaire. RESULTS: The MCO group had an appetite score of 3.00 (1.00-5.50) and 3.00 (1.00-5.00) at the beginning and at the end of the treatment period, respectively, while the high-flux group had 1.00 (0.25-6.00) and 2.00 (0.75-3.25). There were no effects of treatment (P = .573), time (P = .376), and interaction (P = .770) between the MCO and high-flux groups. Leptin levels, at the beginning and at the end of the treatment period, were 2,342.30 (1,156.50-4,091.50) and 2,571.50 (1,619.40-4,036.47) pg/mL in the MCO group, respectively, and 2,183.15 (1,550.67-3,656.50) and 2,685.65 (1,458.20-3,981.08) pg/mL in the high-flux group. There was a time effect (P = .014), showing an increase in leptin levels in both groups, while treatment (P = .771) or interaction (P = .218) effects were not observed. CONCLUSIONS: There is no difference between the effects of MCO or high-flux membranes on leptin levels or appetite of CKD patients on hemodialysis.
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Leptina , Insuficiencia Renal Crónica , Humanos , Apetito , Diálisis Renal , Insuficiencia Renal Crónica/terapiaRESUMEN
TLR expression in neutrophils and monocytes is associated with increased cytokine synthesis, resulting in increased inflammation. However, the inflammatory pathway related to TLR and cathelicidin expression in these cells from CKD patients is unclear. To evaluate TLR4, cathelicidin, TNF-α, IL-6, IL-10 and MCP-1 expression in neutrophils and monocytes from HD and CKD patients. Blood samples were drawn from 47 CKD and 43 HD patients and 71 age and gender-matched healthy volunteers (CONT). TLR4 was analyzed using flow cytometry. Cathelicidin, TNF-α, IL-6, IL-10 and MCP-1 were analyzed via ELISA.TLR4 expression in neutrophils was higher in HD patients than in stage 3 and 4 CKD patients. In these cells, we observed a positive correlation between TLR4 and cathelicidin, TNF-α, IL-6, IL-10 and MCP-1 levels. In monocytes, TLR4 expression was significantly higher in CKD 3 and 4 groups than in the control and HD groups and positively and negatively correlated with IL-6 and MCP-1 and cathelicidin, respectively. TNF-α, IL-6 and MCP-1 serum levels were higher in HD and CKD patients than in control. Cathelicidin and IL-10 levels were only higher in HD patients. IL-6 serum levels were positively correlated with all cytokines, and cathelicidin was negatively correlated with MCP-1 (r = - 0.35; p < 0.01) and positively correlated with IL-10 (r = 0.37; p = 0.001). These results suggest that a uremic environment induces high TLR4, cathelicidin and cytokine expression and may increase inflammation. Thus, future studies should be conducted to evaluate whether TLR4 and cathelicidin should be targets for anti-inflammatory therapeutic strategies.
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Péptidos Catiónicos Antimicrobianos/metabolismo , Citocinas/metabolismo , Inflamación/metabolismo , Monocitos/metabolismo , Neutrófilos/metabolismo , Insuficiencia Renal Crónica/metabolismo , Receptor Toll-Like 4/metabolismo , Adulto , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Inflamación/etiología , Inflamación/patología , Masculino , Persona de Mediana Edad , Monocitos/patología , Neutrófilos/patología , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/patología , CatelicidinasRESUMEN
BACKGROUND: Hemodialysis has been described as an important risk factor for the development of candidemia in patients suffering from chronic renal failure. AIMS: The aim of this study was to evaluate the epidemiology of candidemia in outpatients with renal replacement therapy (RRT) by hemodialysis where the fungemia clearly represents a healthcare-associated infection. METHODS: We retrospectively collected clinical and laboratory data from patients undergoing at least 3 months of RRT by hemodialysis who developed candidemia within 48h of hospital admission. RESULTS: We identified 14 patients with candidemia with central venous catheters (CVC) in place for 11-277 days before developing fungemia. Deep-seated infection was documented in 6 out of 14 candidiasis cases (43%), including 5 cases of endocarditis (36%). CONCLUSIONS: CVC in patients under RRT should be promptly replaced by fistulas and grafts to avoid bloodstream infections. Facing a case of candidemia, adequate source control and prompt initiation of antifungal therapy are mandatory to avoid morbidity and mortality.
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Candidiasis Invasiva/epidemiología , Infecciones Relacionadas con Catéteres/epidemiología , Cateterismo Venoso Central/efectos adversos , Infección Hospitalaria/epidemiología , Diálisis Renal/efectos adversos , Adulto , Anciano , Brasil/epidemiología , Candidemia/epidemiología , Candidemia/etiología , Candidemia/microbiología , Candidiasis Invasiva/etiología , Candidiasis Invasiva/microbiología , Infecciones Relacionadas con Catéteres/etiología , Infecciones Relacionadas con Catéteres/microbiología , Catéteres Venosos Centrales/efectos adversos , Catéteres Venosos Centrales/microbiología , Infección Hospitalaria/etiología , Infección Hospitalaria/microbiología , Susceptibilidad a Enfermedades , Endocarditis/epidemiología , Endocarditis/etiología , Endocarditis/microbiología , Endoftalmitis/epidemiología , Endoftalmitis/etiología , Endoftalmitis/microbiología , Infecciones Fúngicas del Ojo/epidemiología , Infecciones Fúngicas del Ojo/etiología , Infecciones Fúngicas del Ojo/microbiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Diálisis Renal/métodos , Estudios Retrospectivos , Factores de Tiempo , Adulto JovenRESUMEN
BACKGROUND: Endothelial dysfunction is considered an early step of atherosclerotic vascular disease. Asymmetric dimethylarginine (ADMA), the main endogenous inhibitor of nitric oxide synthase (NOS), plays a critical role in the process of atherosclerosis in a uremic environment. Increased plasma ADMA not only works as a cardiovascular morbidity biomarker but it is also involved in the genesis of atherosclerosis in renal disease. Considering the relationships of apolipoprotein E(ApoE) polymorphism with LDL cholesterol (LDL-C) levels and coronary risk, it is possible that it brings on susceptibility to endothelial dysfunction and atherogenesis seen on uremia. METHODS: Six hundred twenty patients were stratified according to glomerular filtration rate (GFR) estimated by Chronic Kidney Disease Epidemiology Collaboration (CKDEPI) formula: group I > 60 mL/min, group II ≤ 60 mL/min and > 15 mL/min, and group III ≤ 15 mL/min or in hemodialysis. Polymorphic ApoE analysis was performed by polymerase chain reaction amplification (PCR). Plasma ADMA levels were measured by high performance liquid chromatography (HPLC). Groups were compared on clinical and laboratory characteristics as well as allele and genotype distribution towards. RESULTS: The ε2 allele of ApoE was present in 62 (10.3 %) patients, ε3 allele in 581 (96.2 %), and ε4 allele in 114 (18.9 %). Their distribution among the 3 groups was uniform. Such uniformity was not observed when we considered endothelial function measured by asymmetric dimethylarginine. In group III, the frequency of ε4 allele was significantly lower in the third tertile compared with the first tertile (14.7 versus 53.3 %, P = 0.000; Pearson chi-square). In groups I and II, there was no difference in allele frequency according to ADMA levels. This association remained significant even after confouding factors corrections (OR 0.329, 95 % CI 0.155 - 0.699, P = 0.004). CONCLUSIONS: The results of this study shows that the frequency of ε4 allele of ApoE is significantly lower among hypertensive patients on hemodialysis with the highest levels of ADMA. Uremia is capable of determining lower plasma ADMA levels in hypertensive ε4 allele carriers.
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Apolipoproteínas E/genética , Arginina/análogos & derivados , Hipertensión/genética , Hipertensión/fisiopatología , Pruebas de Función Renal , Riñón/fisiopatología , Polimorfismo Genético , Alelos , Arginina/metabolismo , Demografía , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Grupos Raciales/genética , Terapia de Reemplazo RenalRESUMEN
BACKGROUND: Infection is the leading cause of morbidity and the second leading cause of mortality in patients on renal replacement therapy. The rates of bloodstream infection in hemodialysis patients vary according to the type of venous access used. Gram-positive bacteria are most frequently isolated in blood cultures of hemodialysis patients. This study evaluated risk factors for the development of bloodstream infections in patients undergoing hemodialysis. METHODS: Risk factors associated with bloodstream infections in patients on hemodialysis were investigated using a case-control study conducted between January 2010 and June 2013. Chronic renal disease patients on hemodialysis who presented with positive blood cultures during the study were considered as cases. Controls were hemodialysis patients from the same institution who did not present with positive blood cultures during the study period. Data were collected from medical records. Logistic regression was used for statistical analysis. RESULTS: There were 162 patients included in the study (81 cases and 81 controls). Gram-positive bacteria were isolated with the highest frequency (72%). In initial logistic regression analysis, variables were hypertension, peritoneal dialysis with previous treatment, type and time of current venous access, type of previous venous access, previous use of antimicrobials, and previous hospitalization related to bloodstream infections. Multiple regression analysis showed that the patients who had a central venous catheter had an 11.2-fold (CI 95%: 5.17-24.29) increased chance of developing bloodstream infections compared with patients who had an arteriovenous fistula for vascular access. Previous hospitalization increased the chance of developing bloodstream infections 6.6-fold (CI 95%: 1.9-23.09). CONCLUSIONS: Infection prevention measures for bloodstream infections related to central venous catheter use should be intensified, as well as judicious use of this route for vascular access for hemodialysis. Reducing exposure to the hospital environment through admission could contribute to a reduction in bloodstream infections in this population.
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Derivación Arteriovenosa Quirúrgica/estadística & datos numéricos , Bacteriemia/epidemiología , Catéteres Venosos Centrales/estadística & datos numéricos , Hipertensión/epidemiología , Fallo Renal Crónico/terapia , Diálisis Peritoneal/estadística & datos numéricos , Diálisis Renal/estadística & datos numéricos , Infecciones Estafilocócicas/epidemiología , Adulto , Anciano , Brasil/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Fallo Renal Crónico/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Factores de Riesgo , Staphylococcus aureusRESUMEN
BACKGROUND: Infection is the leading cause of morbidity and the second most frequent cause of mortality among patients on renal replacement therapy. A major morbid event in this population is hospitalization because of infection. The aim of this study was to investigate the risk factors for morbidity and mortality related to bloodstream infection (BSI) among patients on hemodialysis. RESULTS: Risk factors for morbidity and mortality related to BSI in patients on hemodialysis were investigated retrospectively by nested case-control, from January 2010 to June 2013. Patients were divided into two groups: those who progressed to hospitalization or death due to BSI (Group 1) and those who developed BSI, but did not progress to the same outcome (Group 2). Data were collected through consultation of patient records. For statistical analysis, logistic regression was used. There were 32 patients in Group 1 and 61 in Group 2. Logistic regression verified that, for each year of age, the chance of death or hospitalization for BSI increased 1.05 times [95% confidence interval (CI): 1.02-1.09]. Patients with BSI caused by Staphylococcus aureus had an 8.67 times higher chance of progressing to death or hospitalization (95% CI: 2.5-30.06). The isolation of multiresistant microorganisms in blood cultures of hemodialysis patients increased morbidity and mortality by 2.75 times (95% CI: 1.01-7.48). CONCLUSION: Independent risk factors for morbidity and mortality among patients after developing BSI during hemodialysis were: age, blood culture positive for S. aureus, and antibiotic resistance. Control measures to prevent microbial dissemination, primarily the multiresistant ones, should be intensified in this population. More studies are needed to standardize specific measures not yet classically standardized, such as collection of surveillance culture samples, contact precautions, and decolonization.
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Diálisis Renal/efectos adversos , Sepsis/fisiopatología , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Sepsis/etiología , Sepsis/mortalidadRESUMEN
OBJECTIVES: This prospective study, conducted at the dialysis unit of the Nephrology Division, Federal University of Sao Paulo-Oswaldo Ramos Foundation, Brazil, aimed to evaluate whether waist circumference (WC) can predict adiponectin levels in patients undergoing peritoneal dialysis (PD). METHODS: Among 115 patients on PD at a single dialysis center who were evaluated at 6 and 12 months, 57% were men, 31% had diabetes, mean age was 52.8 ± 16.1 years, body mass index was 25 ± 4.3 kg/m(2), and dialysis vintage was 13 months (range: 5 - 33 months). We measured WC at the umbilicus level. Adiponectin was determined by an enzyme-linked immunosorbent assay. RESULTS: At baseline, WC was inversely associated with adiponectin (r = -0.48, p < 0.01). After adjustment for sex, age, diabetes, peritoneal clearance, and residual renal function, WC was an independent determinant of serum adiponectin (ß = -0.52; 95% confidence interval: -0.73 to -0.31; p < 0.001). In the prospective analysis, after adjustment for confounders, changes in WC predicted changes in adiponectin. For each unit increase in WC, adiponectin declined by 0.39 mg/L (p < 0.001). CONCLUSIONS: This study demonstrates that WC is associated with adiponectin and, more importantly, that this simple marker of central adiposity was able to predict changes in adiponectin levels over time.
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Adiponectina/sangre , Diálisis Peritoneal , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/terapia , Circunferencia de la Cintura , Grasa Abdominal , Adiposidad , Adulto , Anciano , Brasil , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de TiempoRESUMEN
BACKGROUND: Waist circumference (WC) has been well recognized as a surrogate marker of abdominal adiposity. In peritoneal dialysis (PD) patients, however, aspects related to this dialysis modality, such as abdominal distension, presence of catheter and frequent hernia, raise questions regarding the reliability of WC measurements. Herein, we investigated for the first time whether WC is a reliable marker of abdominal adiposity in PD population. METHODS: This study included 107 prevalent PD patients [56% male, age 52 ± 17 years, 35% diabetics, body mass index (BMI) 24.8 ± 3.9 kg/m(2)]. WC measured at umbilicus level was evaluated against the trunk fat assessed by dual-energy x-ray absorptiometry at baseline and after 6 months. All measurements were taken with the empty abdominal cavity. RESULTS: At baseline, a strong correlation of WC with trunk fat (r = 0.81; P < 0.001) was observed. Adjusting for gender, age, dialysis vintage and BMI, WC was independently associated with trunk fat (ß = 0.30; P < 0.001; R(2) = 0.77). The agreement between WC and trunk fat was 0.59 (kappa statistic) and the area under the curve was 0.90. In the prospective evaluation, we observed that changes in WC correlated with changes in trunk fat as well (r = 0.49; P < 0.001). The kappa statistic of 0.48 remained indicative of a moderate agreement between the methods. The receiver operating characteristic curve analysis showed that WC was sensitive to detect changes in trunk fat (area under the curve 0.76). In the logistic regression analysis adjusting for gender, age and BMI, changes in WC were independently associated with changes in trunk fat. CONCLUSION: The simple anthropometric method of WC is a reliable marker of abdominal adiposity in PD patients.
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Grasa Abdominal/diagnóstico por imagen , Fallo Renal Crónico/terapia , Diálisis Peritoneal/métodos , Circunferencia de la Cintura , Absorciometría de Fotón/métodos , Adulto , Anciano , Biomarcadores/análisis , Análisis Químico de la Sangre , Índice de Masa Corporal , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Fallo Renal Crónico/diagnóstico , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Diálisis Peritoneal/efectos adversos , Estudios Prospectivos , Curva ROC , Medición de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
ABSTRACT Objective: Reuse of hemodialysis filters is a standard practice and the sterilizing chemical most often employed is peracetic acid. Before starting the dialysis session, filters and lines are checked for residual levels of peracetic acid by means of a non-quantitative colorimetric test that is visually interpreted. The objective of this study was to investigate a new quantitative spectrophotometric test for detection of peracetic acid residues. Methods: Peracetic acid solutions were prepared in concentrations ranging from 0.01 to 10 ppm. A reagent (potassium-titanium oxide + sulfuric acid) was added to each sample in proportions varying from 0.08 to 2.00 drops/mL of solution. Optical densities were determined in a spectrophotometer using a 405-nm filter and subjected to visual qualitative test by different observers. Results: A relation between peroxide concentrations and respective optical densities was observed and it was linear with R2 > 0.90 for all reagent/substrate proportions. The peak optical densities were obtained with the reagent/substrate ratio of 0.33 drops/mL, which was later standardized for all further experiments. Both qualitative and quantitative tests yielded a specificity of 100%. The quantitative test was more sensitive than the qualitative test and resulted in higher positive and negative predictive values. There was a difference between observers in the qualitative test and some samples with significant amounts of peroxide were not detected. Conclusion: A quantitative spectrophotometric test may improve detection of residues of peracetic acid when compared to the standard visual qualitative test. This innovation may contribute to the development of safer standards for reuse of hemodialysis filters.
RESUMO Objetivo: A reutilização de filtros de hemodiálise é uma prática disseminada e a substância química esterilizante mais empregada é o ácido peracético. Antes de iniciar a sessão de diálise, os filtros e as linhas são verificados em relação a níveis residuais de ácido peracético por meio de teste colorimétrico não quantitativo, com interpretação visual. O objetivo deste trabalho foi investigar um novo teste espectrofotométrico quantitativo para detecção de resíduos de ácido peracético. Métodos: As soluções de ácido peracético foram preparadas em concentrações que variam de 0,01 a 10 ppm. O reagente (óxido de potássio-titânio + ácido sulfúrico) foi acrescentado a cada amostra em proporções que variaram de 0,08 a 2,00 gotas/mL de solução. As densidades ópticas foram determinadas em um espectrofotômetro com filtro de 405 nm e submetidas a um teste visual qualitativo por diferentes observadores. Resultados: Observou-se a relação linear entre as concentrações de peróxido e as respectivas densidades ópticas com R2 > 0,90 para todas as proporções de reagente/substrato. As maiores densidades ópticas foram obtidas com a proporção reagente/substrato de 0,33 gotas/mL, que foi padronizada para todos os experimentos posteriores. Os testes qualitativos e quantitativos apresentaram especificidade de 100%. O teste quantitativo foi mais sensível do que o qualitativo e apresentou maiores valores preditivos positivos e negativos. Houve uma diferença entre os observadores no teste qualitativo e algumas amostras com quantidade significativa de peróxido não foram detectadas. Conclusão: O teste espectrofotométrico quantitativo pode melhorar a detecção de resíduos de ácido peracético em comparação ao teste visual qualitativo padrão. Essa inovação pode contribuir para o desenvolvimento de padrões mais seguros na reutilização de filtros de hemodiálise.
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Polymorphonuclear leukocytes (PMNs) from chronic kidney disease (CKD) patients display accelerated apoptosis and dysfunction, which may predispose CKD patients to infections. In this study, we investigated the effect of spermidine and p-cresol on apoptosis and function on PMN from healthy subjects. We measured the effect of spermidine and p-cresol on apoptosis, ROS production unstimulated and stimulated (S. aureus and PMA) and expression of CD95, caspase 3, and CD11b on PMN. After incubation with p-cresol and spermidine, we did not observe any changes in apoptosis, viability or expression of caspase 3 and CD95 in PMN from healthy subjects. PMN incubated for 10 minutes with spermidine demonstrated a significant reduction in spontaneous, S. aureus and PMA-stimulated ROS production. p-cresol induced a decrease in PMA-stimulated ROS production. Spermidine and p-cresol also induced a decrease in the expression of CD11b on PMN. Spermidine and p-cresol decreased the expression of CD11b and oxidative burst of PMN from healthy subjects and had no effect on PMN apoptosis and viability.
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Apoptosis/efectos de los fármacos , Antígeno CD11b/inmunología , Cresoles/farmacología , Neutrófilos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Espermidina/farmacología , Humanos , Neutrófilos/citología , Neutrófilos/inmunología , Neutrófilos/metabolismoRESUMEN
OBJECTIVE: Reuse of hemodialysis filters is a standard practice and the sterilizing chemical most often employed is peracetic acid. Before starting the dialysis session, filters and lines are checked for residual levels of peracetic acid by means of a non-quantitative colorimetric test that is visually interpreted. The objective of this study was to investigate a new quantitative spectrophotometric test for detection of peracetic acid residues. METHODS: Peracetic acid solutions were prepared in concentrations ranging from 0.01 to 10 ppm. A reagent (potassium-titanium oxide + sulfuric acid) was added to each sample in proportions varying from 0.08 to 2.00 drops/mL of solution. Optical densities were determined in a spectrophotometer using a 405-nm filter and subjected to visual qualitative test by different observers. RESULTS: A relation between peroxide concentrations and respective optical densities was observed and it was linear with R2 > 0.90 for all reagent/substrate proportions. The peak optical densities were obtained with the reagent/substrate ratio of 0.33 drops/mL, which was later standardized for all further experiments. Both qualitative and quantitative tests yielded a specificity of 100%. The quantitative test was more sensitive than the qualitative test and resulted in higher positive and negative predictive values. There was a difference between observers in the qualitative test and some samples with significant amounts of peroxide were not detected. CONCLUSION: A quantitative spectrophotometric test may improve detection of residues of peracetic acid when compared to the standard visual qualitative test. This innovation may contribute to the development of safer standards for reuse of hemodialysis filters.
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BACKGROUND AND OBJECTIVES: Coronary artery calcification (CAC) is highly prevalent among patients with chronic kidney disease (CKD), and it has been described as a strong predictor of mortality in the dialysis population. Because there is a lack of information regarding cardiovascular calcification and clinical outcomes in the earlier stages of the disease, we aimed to evaluate the impact of CAC on cardiovascular events, hospitalization, and mortality in nondialyzed patients with CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This is a prospective study including 117 nondialyzed patients with CKD (age, 57 +/- 11.2 years; 61% male; 23% diabetics; creatinine clearance, 36.6 +/- 17.8 ml/min per 1.73 m(2)). CAC was quantified by multislice computed tomography. The occurrence of cardiovascular events, hospitalization, and death was recorded over 24 months. RESULTS: CAC >10 Agatston units (AU) was observed in 48% of the patients [334 (108 to 858.5) AU; median (interquartiles)], and calcification score >or=400 AU was found in 21% [873 (436-2500) AU]. During the follow-up, the occurrence of 15 cardiovascular events, 19 hospitalizations, and 4 deaths was registered. The presence of CAC >10 AU was associated with shorter hospitalization event-free time and lower survival. CAC >or=400 AU was additionally associated with shorter cardiovascular event-free time. Adjusting for age and diabetes, CAC >or=400 AU was independently associated with the occurrence of hospitalization and cardiovascular events. CONCLUSIONS: Cardiovascular events, hospitalization, and mortality were associated with the presence of CAC in nondialyzed patients with CKD. Severe CAC was a predictor of cardiovascular events and hospitalization in these patients.
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Calcinosis/etiología , Enfermedad de la Arteria Coronaria/etiología , Enfermedades Renales/complicaciones , Anciano , Biomarcadores/sangre , Brasil/epidemiología , Calcinosis/diagnóstico por imagen , Calcinosis/mortalidad , Distribución de Chi-Cuadrado , Enfermedad Crónica , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Creatinina/sangre , Femenino , Estudios de Seguimiento , Hospitalización , Humanos , Estimación de Kaplan-Meier , Enfermedades Renales/sangre , Enfermedades Renales/mortalidad , Masculino , Persona de Mediana Edad , Prevalencia , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Tomografía Computarizada por Rayos XRESUMEN
It has been suggested that phosphate binders may reduce the inflammatory state of hemodialysis (HD) patients. However, it is not clear whether it has any effect on oxidative stress. The objective of this study was to evaluate the effect of sevelamer hydrochloride (SH) and calcium acetate (CA) on oxidative stress and inflammation markers in HD patients. Hemodialysis patients were randomly assigned to therapy with SH (n=17) or CA (n=14) for 1 year. Before the initiation of therapy (baseline) and at 12 months, we measured in vitro reactive oxygen species (ROS) production by stimulated and unstimulated polymorphonuclear neutrophils and serum levels of tumor necrosis factor alpha, interleukin-10, C-reactive protein, and albumin. There was a significant reduction of spontaneous ROS production in both groups after 12 months of therapy. There was a significant decrease of Staphylococcus aureus stimulated ROS production in the SH group. There was a significant increase in albumin serum levels only in the SH group. In the SH group, there was also a decrease in the serum levels of tumor necrosis factor alpha and C-reactive protein. Our results suggest that compared with CA treatment, SH may lead to a reduction in oxidative stress and inflammation. Therefore, it is possible that phosphate binders exert pleiotropic effects on oxidative stress and inflammation, which could contribute toward decreasing endothelial injury in patients in HD.
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Mediadores de Inflamación/sangre , Inflamación/sangre , Estrés Oxidativo/efectos de los fármacos , Proteínas de Unión a Fosfato/uso terapéutico , Diálisis Renal/efectos adversos , Acetatos/uso terapéutico , Adulto , Biomarcadores/sangre , Compuestos de Calcio/uso terapéutico , Femenino , Humanos , Inflamación/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Poliaminas/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Sevelamer , Resultado del TratamientoRESUMEN
BACKGROUND: Changes in body fat (BF) were shown to occur over time in peritoneal dialysis (PD) patients. However, the factors associated with BF changes have not been fully investigated in this population. METHODS: We studied 45 patients (25 were male; age, 53, SD +/- 15 years; 21 continuous ambulatory peritoneal dialysis/24 automated peritoneal dialysis; PD vintage, 14 ([range, 3 to 104] months; 40% were diabetic; 31% were previously treated by hemodialysis). Body composition was assessed by dual-energy X-ray absorptiometry and bioelectric impedance analysis, nutritional status was assessed by subjective global assessment, energy intake was assessed by 3-day food records, and resting energy expenditure (REE) was assessed by indirect calorimetry. Glucose absorption, serum bicarbonate, and C-reactive protein were also evaluated. All measurements were performed at baseline and after 12 months. RESULTS: Large variability in BF changes was observed among patients: 53% gained BF (+3.0 +/- 2.8), whereas 47% lost BF (-2.3, SD +/- 1.4). At baseline, groups were similar regarding sex, age, percent diabetics, DP modality, characteristics of peritoneal transport, residual renal function, energy intake, glucose absorption, and REE. However, patients who gained BF had lower BF (16.3, SD +/- 6.9 kg, versus 20.9, SD +/- 6.5 kg; P = .03), had a higher ratio of total energy offered (intake plus absorbed glucose) to REE (1.45, SD +/- 0.39, versus 1.26, SD +/- 0.24; P = .04), and were on PD for a shorter time (10 [range, 3 to 104] versus 20 [range, 4 to 76] months; P = .03). This group also had a higher proportion of malnourished patients (50% versus 19%; P = .03) and of patients previously treated by hemodialysis (46% versus 14%; P = .03). After 12 months, a reduction in the frequency of malnutrition (50% to 25%; P = .02) was observed in the group of patients with increased BF. Patients who lost BF reduced their body cell mass (from 21.7 [SD +/- 5.1 kg] to 20.7 [SD +/- 5.0 kg]; P < .01) and level of serum bicarbonate (from 22.7 [SD +/- 3.7 mmol/L] to 20.9 [SD +/- 3.1 mmol/L]; P < .01). Moreover, this group had an increase in frequency of malnutrition (from 19% to 38%; P = .02), a reduction in the proportion of patients with residual renal function (from 62% to 43%; P = .03), and a higher number of hospitalizations (from 25% to 4%; P = .02) during follow-up. Glucose absorption and C-reactive protein were not associated with BF changes. A regression analysis showed that baseline body mass index was independently associated with a gain of BF (-0.19, SE = 0.09, P = .04), and that hospitalization during follow-up was associated with a loss of BF (2.35, SE = 1.19, P = .04). CONCLUSIONS: Prevalent PD patients exhibited a large variability in BF changes. Baseline body mass index and hospitalizations during follow-up were the most important factors associated with these changes.
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Tejido Adiposo/metabolismo , Metabolismo Basal/fisiología , Composición Corporal/fisiología , Estado Nutricional , Diálisis Peritoneal , Absorciometría de Fotón/métodos , Calorimetría Indirecta , Registros de Dieta , Impedancia Eléctrica , Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios ProspectivosRESUMEN
Introdução: A avaliação do consumo alimentar, particularmente da ingestão de proteínas, constitui uma ferramenta importante na prevenção, tratamento emonitoramento da desnutrição nos pacientes em hemodiálise. Para tanto, os métodos mais comumente utilizados na prática clínica são o registro alimentar eo equivalente protéico do aparecimento de nitrogênio (PNA). Objetivo: Avaliar a concordância entre o registro alimentar e o PNA para a estimativa da ingestãoprotéica nos pacientes em hemodiálise. Casuística e Métodos: Foram estudados 39 pacientes (67% homens, 46,8±14,7anos, IMC 23,5±4,6kg/m2) emtratamento hemodialítico. Os critérios de exclusão foram presença de doenças catabólicas, função renal residual e uso de glucocorticóides. O registro alimentarfoi preenchido durante três dias e o PNA foi calculado conforme recomendado pelo NKF-DOQI. Resultados: A ingestão protéica obtida pelo registro alimentarfoi menor que aquela obtida pelo PNA (56,3±23,4 vs 67,9±23,9g/dia, respectivamente; P≤0,001). Os métodos apresentaram uma boa correlação (r=0,54;P<0,001), porém uma grande variabilidade individual foi observada (-51,7 a +28,5g/dia). A ingestão protéica obtida por ambos os métodos correlacionou-sepositivamente com o IMC (registro alimentar: r=0,41 e PNA r=0,80; P<0,05). A diferença entre os métodos (registro alimentar - PNA) correlacionou-senegativamente com o IMC (r=-0,49; P<0,01). A análise por subgrupos de IMC mostrou que o registro alimentar subestimava a ingestão protéica em relação aoPNA apenas nos pacientes com IMC≥25kg/m2. A regressão linear múltipla apontou o IMC≥25kg/m2 como único fator independentemente associado àsvariações entre os métodos. [β =-16,9 (-31,1 a -2,8); P=0,02] Conclusão: O método do registro alimentar exibiu valores menores de proteínas em relação aométodo do PNA nos pacientes em hemodiálise, sendo a condição de sobrepeso/obesidade um importante determinante destas variações.
Introduction: The assessment of food consumption, particularly of protein intake, constitutes an important tool in the prevention, treatment, and monitoringof malnutrition in hemodialysis patients. Food record and protein equivalent of nitrogen appearance (PNA) are the most commonly used methods for suchpurpose in the clinical practice. Aim: To evaluate the agreement between food record and PNA for the assessment of protein intake in hemodialysis patients.Subjects and Methods: Thirty-nine hemodialysis patients (67% male, 46.8 ± 14.7 years old, BMI 23.5 ± 4.6 kg/m2) were studied. The exclusion criteriawere catabolic illnesses, residual renal function and use of glucocorticoids. Food intake was recorded 3 days and PNA was calculated as proposed by theNKF-DOQI. Results: The protein intake assessed by food record was lower than that obtained by PNA (56.3 ± 23.4 vs 67.9 ± 23.9 g/day, respectively;P≤0.001). The methods were well correlated (r=0.54; P<0.001), however, a large individual variability was observed (-51.7 to +28.5 g/day). The protein intakeobtained by both methods correlated positively with BMI (food record: r=0.41 and PNA: r=0.80; P<0.05). The difference between the methods (food record,PNA) correlated negatively with BMI (r=-0.49; P<0.001). The analysis by subgroups of BMI showed that the food record method underestimated proteinintake in relation to PNA only in patients with BMI ≥25kg/m2. The multiple linear regression analysis pointed to BMI ≥25kg/m2 as a factor independentlyassociated with variations between the methods. Conclusion: The food record method showed lower values of protein in comparison with the PNA methodin hemodialysis patients, and overweight/obesity status was an important determinant of these variations.
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano de 80 o más Años , Diálisis Renal , Ingestión de Alimentos , Fallo Renal Crónico/dietoterapia , Nitrógeno/metabolismo , ProteínasRESUMEN
In an in vivo crossover trial, we compared a cellulosic with a synthetic dialyzer with respect to polymorphonuclear cells (PMN) function and apoptosis, cytokine serum levels and synthesis by peripheral blood mononuclear cells (PBMC), and complement activation. Twenty hemodialysis (HD) patients were assigned in alternate order to HD with cellulose acetate (CA) or polysulfone (PS) dialyzer. After 2 weeks, patients were crossed over to the second dialyzer and treated for another 2 weeks. Apoptosis was assessed by flow cytometry in freshly isolated PMN. Phagocytosis and production of peroxide by PMN were studied by flow cytometry in whole blood. PBMC were isolated from blood samples and incubated for 24 h with or without lipopolysaccharide (LPS). There was no impact of dialyzer biocompatibility on PMN apoptosis and function, cytokine synthesis by PBMC or on their serum levels, serum levels of C3a, and terminal complement complex (TCC). Nevertheless, after HD, serum levels of complement correlated negatively with PMN phagocytosis and peroxide production, and positively with PMN apoptosis and cytokine production by PBMC. Although the results did not show a dialyzer advantage on the immunologic parameters, complement activation may have modulated cell function and apoptosis after HD.