Infarto renal agudo: características clínicas y factores pronósticos / Acute renal infarction: Clinical characteristics and prognostic factors

Introducción: El infarto renal agudo (INRA) es una patología de diagnóstico infrecuente, cuya incidencia real es probablemente superior a la detectada, y que asocia una evolución desfavorable en un alto porcentaje de casos. Objetivos: Describir las principales características clínicas, bioquímicas y radiológicas, y determinar qué factores se asocian a una peor evolución (muerte o deterioro permanente de la función renal). Material y métodos: Estudio retrospectivo y observacional, que incluyó a todos los pacientes diagnosticados de INRA mediante TAC con contraste en un único hospital durante 18 años. Los pacientes fueron clasificados según el origen cardiogénico o no cardiogénico del INRA. Se analizaron las principales características clínicas, bioquímicas y radiológicas, y, mediante un modelo de regresión logística multivariante, se determinaron los factores asociados a una peor evolución. Resultados: Se incluyeron 62 casos, de los que 30 fueron de origen cardiogénico. Los 32 pacientes con INRA no cardiogénico eran más jóvenes, con menos comorbilidad y menor frecuencia de tratamiento previo con anticoagulación. La extensión media de daño isquémico por radiología fue del 35%, sin observarse diferencias entre los subgrupos etiológicos. El 38% de los pacientes tuvo una evolución desfavorable, y los principales determinantes fueron: la función renal al diagnóstico (eGFR) (OR=0,949; IC 95%: 0,918-0,980; p=0,002) y la anticoagulación oral antes del episodio agudo (OR=0,135; IC 95%: 0,032-0,565; p=0,006). Conclusiones: El INRA es una patología infrecuente, con manifestaciones clínicas poco específicas y, en más de la mitad de los casos, no asociada a enfermedad cardiaca o arritmias. Una alta proporción de pacientes evoluciona desfavorablemente. La función renal al diagnóstico es uno de los principales factores pronósticos (AU)

Introduction: Acute renal infarction (ARI) is an uncommon disease, whose real incidence is probably higher than expected. It is associated with poor prognosis in a high percentage of cases. Objectives: To describe the main clinical, biochemical and radiologic features and to determine which factors are associated with poor prognosis (death or permanent renal injury). Materials and methods: The following is a retrospective, observational, single-hospital-based study. All patients diagnosed with ARI by contrast-enhanced computed tomography (CT) over an 18-year period were included. Patients were classified according to the cardiac or non-cardiac origin of their disease. Clinical, biochemical and radiologic features were analysed, and multiple logistic regression model was used to determine factors associated with poor prognosis. Results: A total of 62 patients were included, 30 of which had a cardiac origin. Other 32 patients with non-cardiac ARI were younger, had less comorbidity, and were less frequently treated with oral anticoagulants. CT scans estimated mean injury extension at 35%, with no differences observed between groups. A total of 38% of patients had an unfavourable outcome, and the main determinants were: Initial renal function (OR=0.949; IC 95% 0.918-0.980; p=0.002), and previous treatment with oral anticoagulants (OR=0.135; IC 95% 0.032-0.565; p=0.006). Conclusions: ARI is a rare pathology with non-specific symptoms, and it is not associated with cardiological disease or arrhythmias in more than half of cases. A substantial proportion of patients have unfavourable outcomes, and the initial renal function is one of the main prognostic factors (AU)

Acute renal infarction: Clinical characteristics and prognostic factors.

INTRODUCTION: Acute renal infarction (ARI) is an uncommon disease, whose real incidence is probably higher than expected. It is associated with poor prognosis in a high percentage of cases. OBJECTIVES: To describe the main clinical, biochemical and radiologic features and to determine which factors are associated with poor prognosis (death or permanent renal injury). MATERIALS AND METHODS: The following is a retrospective, observational, single-hospital-based study. All patients diagnosed with ARI by contrast-enhanced computed tomography (CT) over an 18-year period were included. Patients were classified according to the cardiac or non-cardiac origin of their disease. Clinical, biochemical and radiologic features were analysed, and multiple logistic regression model was used to determine factors associated with poor prognosis. RESULTS: A total of 62 patients were included, 30 of which had a cardiac origin. Other 32 patients with non-cardiac ARI were younger, had less comorbidity, and were less frequently treated with oral anticoagulants. CT scans estimated mean injury extension at 35%, with no differences observed between groups. A total of 38% of patients had an unfavourable outcome, and the main determinants were: Initial renal function (OR=0.949; IC 95% 0.918-0.980; p=0.002), and previous treatment with oral anticoagulants (OR=0.135; IC 95% 0.032-0.565; p=0.006). CONCLUSIONS: ARI is a rare pathology with non-specific symptoms, and it is not associated with cardiological disease or arrhythmias in more than half of cases. A substantial proportion of patients have unfavourable outcomes, and the initial renal function is one of the main prognostic factors.

Choosing conservative therapy in chronic kidney disease.

INTRODUCTION: Incidence of use for various renal replacement therapies is well-known, but no data are available on conservative treatment use. OBJECTIVE: To assess the proportion of patients with chronic kidney failure receiving a conservative treatment. RESULTS: From July 1, 2013 to June 30, 2014, 232 patients with stage 5 CKD were seen in the Nephrology Department. After having received information on existing therapeutic options and having known the opinion of their treating physicians, 81 patients (35%) selected hemodialysis, 56 (24%) preferred peritoneal dialysis, 5 (2%) selected a preemptive transplant from a living donor, and in 90 (39%) a conservative treatment option was selected. In a univariate analysis using logistic regression, variables associated to a preference for conservative treatment were age, Charlson index excluding age, degree of walking difficulties, and functional dependence level, with the first three factors achieving statistical significance in a multivariate analysis. Presence of a severe disease resulting in a poor prognosis was the main reason for selecting a conservative treatment (49%), with the second one being patient refusal to receive a renal replacement therapy (26%). Mortality rate was 8.2/100 patient-months in conservative therapy group versus 0.6/100 patient-months in patients receiving renal replacement therapy (P<.001). In patients receiving conservative therapy, baseline glomerular filtration rate at the time of study enrollment was the sole variable showing a significant impact on survival. CONCLUSIONS: About 39% of patients with stage 5 CKD seen over a 1-year period in the Nephrology Department received conservative therapy. Age, co-morbidity, and functional disability were the factors associated to selecting a conservative therapy option.

Elección de tratamiento conservador en la enfermedad renal crónica / Choosing conservative therapy in chronic kidney disease

Introducción: La incidencia de las diversas modalidades de tratamiento sustitutivo renal es conocida, pero no sucede así con la opción de tratamiento conservador. Objetivo: Conocer la proporción de pacientes con insuficiencia renal crónica sometidos a tratamiento conservador. Resultados: Entre el 1 de julio de 2013 y el 30 de junio de 2014 fueron atendidos en el Servicio de Nefrología 232 casos con ERC en estadio 5. Tras recibir una información sobre las diversas alternativas terapéuticas y con la opinión del médico responsable, 81 enfermos (35%) optaron por el tratamiento con hemodiálisis, 56 (24%) mostraron preferencia por la diálisis peritoneal, 5 (2%) por el trasplante de vivo prediálisis, y en 90 enfermos (39%) se decidió realizar tratamiento conservador. En el análisis univariante de regresión logística las variables asociadas a la elección de tratamiento conservador fueron la edad, el índice de Charlson sin contar la edad, el grado de dificultad para la marcha y el grado de dependencia funcional, quedando los 3 primeros con significación significativa en el análisis multivariante. La existencia de una enfermedad grave con mal pronóstico a corto plazo fue la principal causa por la que se indicó el tratamiento conservador (49%), y la segunda fue la negativa del enfermo a recibir tratamiento sustitutivo renal (26%). La tasa de mortalidad fue de 8,2/100 enfermos-mes en el grupo de tratamiento conservador y de 0,6/100 enfermos-mes en el grupo que decidió optar al tratamiento sustitutivo renal (p<0,001). En el grupo tratado de forma conservadora, el filtrado glomerular en el momento de inclusión en el estudio fue la única variable que influyó de forma estadísticamente significativa sobre la supervivencia. Conclusiones: El 39% de los pacientes con ERC en estadio 5 atendidos durante un año en el Servicio de Nefrología fueron tratados de forma conservadora. Edad, comorbilidad y discapacidad funcional fueron las variables que se relacionaron con la elección de tratamiento conservador (AU)

Introduction: Incidence of use for various renal replacement therapies is well-known, but no data are available on conservative treatment use. Objective: To assess the proportion of patients with chronic kidney failure receiving a conservative treatment. Results: From July 1, 2013 to June 30, 2014, 232 patients with stage 5 CKD were seen in the Nephrology Department. After having received information on existing therapeutic options and having known the opinion of their treating physicians, 81 patients (35%) selected hemodialysis, 56 (24%) preferred peritoneal dialysis, 5 (2%) selected a preemptive transplant from a living donor, and in 90 (39%) a conservative treatment option was selected. In a univariate analysis using logistic regression, variables associated to a preference for conservative treatment were age, Charlson index excluding age, degree of walking difficulties, and functional dependence level, with the first three factors achieving statistical significance in a multivariate analysis. Presence of a severe disease resulting in a poor prognosis was the main reason for selecting a conservative treatment (49%), with the second one being patient refusal to receive a renal replacement therapy (26%). Mortality rate was 8.2/100 patient-months in conservative therapy group versus 0.6/100 patient-months in patients receiving renal replacement therapy (P<.001). In patients receiving conservative therapy, baseline glomerular filtration rate at the time of study enrollment was the sole variable showing a significant impact on survival. Conclusions: About 39% of patients with stage 5 CKD seen over a 1-year period in the Nephrology Department received conservative therapy. Age, co-morbidity, and functional disability were the factors associated to selecting a conservative therapy option (AU)

Mantenimiento de la función renal residual en hemodiálisis: experiencia de 5 años de una pauta de diálisis incremental / Maintaining residual renal function in patients on haemodialysis: 5-year experience using a progressively increasing dialysis regimen

Introducción: A diferencia de los pacientes tratados con diálisis peritoneal, la programación de una dosis incremental de diálisis no se considera en el enfermo tratado con hemodiálisis (HD) periódica, ni tampoco es habitual tener en cuenta la función renal residual en el cálculo de la dosis total de diálisis, asumiéndose como tal la proporcionada exclusivamente por el aclaramiento del dializador. A partir del año 2006 decidimos establecer una pauta incremental de diálisis al inicio del tratamiento renal sustitutivo, valorando la posibilidad de comenzar con 2 HD/semana cuando el aclaramiento renal de urea fuera igual o superior a 2,5 ml/min. En el presente trabajo presentamos nuestra experiencia de los primeros 5 años de aplicación de esta pauta incremental de HD y su repercusión sobre la función renal residual. Metodología: Se han incluido a todos los enfermos que iniciaron tratamiento con HD periódica entre el 1/1/2006 y el 30/9/2010, y permanecieron en diálisis más de tres meses. El seguimiento de los enfermos finalizó el 31/12/2010 (fecha de cierre del estudio). Cuando un enfermo inicia HD se determina el aclaramiento de urea y creatinina con las concentraciones de urea y creatinina en una muestra de sangre obtenida antes de la diálisis y (..) (AU)

Introduction: In contrast to patients treated with peritoneal dialysis, those on periodical haemodialysis (HD) do not receive programmed progressive increases in dialysis dosage, nor is residual renal function taken into account in the calculation of the total dialysis prescription; rather, only dialyser clearance is factored into the equation. In 2006, we decided to establish a progressively increasing dialysis regimen at the start of renal replacement therapy, evaluating the possibility of starting with 2 sessions of HD/week when renal clearance of urea was equal to or greater than 2.5ml/min. This study summarises our experience during the first 5 years of application of this progressively increasing HD prescription and its repercussions on residual renal function. Methods: We included all patients who started periodical HD between 1/1/2006 and 30/9/2010 and remained on dialysis for more than three months. The follow-up period ended on 31/12/2010 (study end date). When a patient started HD, urea and creatinine clearance levels were measured based on urea and creatinine concentrations in blood samples taken before dialysis and in urine samples taken 24 hours prior to starting the first dialysis session of the week. If urea clearance was equal to or greater than 2.5ml/min, 2 sessions of HD per week were applied, as long as the patient's clinical situation allowed for it (according to the criteria of the attending physician). Residual renal function was analysed every 2 months until diuresis was less than 100ml/day, which is considered to be basically null. We evaluated the decrease in residual renal function, calculating the rate of decrease in (..) (AU)

Maintaining residual renal function in patients on haemodialysis: 5-year experience using a progressively increasing dialysis regimen.

INTRODUCTION: In contrast to patients treated with peritoneal dialysis, those on periodical haemodialysis (HD) do not receive programmed progressive increases in dialysis dosage, nor is residual renal function taken into account in the calculation of the total dialysis prescription; rather, only dialyser clearance is factored into the equation. In 2006, we decided to establish a progressively increasing dialysis regimen at the start of renal replacement therapy, evaluating the possibility of starting with 2 sessions of HD/week when renal clearance of urea was equal to or greater than 2.5 ml/min. This study summarises our experience during the first 5 years of application of this progressively increasing HD prescription and its repercussions on residual renal function. METHODS: We included all patients who started periodical HD between 1/1/2006 and 30/9/2010 and remained on dialysis for more than three months. The follow-up period ended on 31/12/2010 (study end date). When a patient started HD, urea and creatinine clearance levels were measured based on urea and creatinine concentrations in blood samples taken before dialysis and in urine samples taken 24 hours prior to starting the first dialysis session of the week. If urea clearance was equal to or greater than 2.5 ml/min, 2 sessions of HD per week were applied, as long as the patient's clinical situation allowed for it (according to the criteria of the attending physician). Residual renal function was analysed every 2 months until diuresis was less than 100ml/day, which is considered to be basically null. We evaluated the decrease in residual renal function, calculating the rate of decrease in glomerular filtration (ml/min/month) and 24-hour diuresis (ml/month) in patients receiving 2 and 3 HD sessions per week. In January 2010, we took a cross-sectional sample, evaluating glomerular filtration and how this value was associated with various clinical and laboratory parameters in patients receiving 2 or 3 dialysis sessions per week. RESULTS: During the study period, 95 patients were included in the study, 41 of which (43%) started with 2 HD sessions per week, and 54 (57%) with 3 sessions per week. The mean time that patients remained on the 2HD sessions/week regimen was 11.1 ± 7.2 months (range: 2-25 months). Of the 41 patients that started with 2 HD sessions/week, 10 received a transplant while on the treatment regimen, 1 was transferred to peritoneal dialysis, 6 recovered renal function and were able to abandon dialysis treatment, 15 were switched to the 3 HD sessions/week regimen, and 9 continued on the 2 HD sessions/week regimen at the time the study ended. Of the 15 patients that were switched to the 3 HD sessions/week regimen, 4 received transplants, 3 died, and the remaining 8 continued on HD until the end of the study. A Kaplan-Meier survival analysis revealed that patients who started on the 2 HD sessions/week regimen had a greater survival rate (log-rank: 3.964; P=.04). Losses in both glomerular filtration rate and 24-hour diuresis were lower in patients on the 2 HD sessions/week regimen: 0.22 ± 0.36 ml/min/month vs 0.89 ± 1.26 ml/min/month for glomerular filtration (P=.001), and 90.59 ± 132 ml/month vs 206.23 ± 286 ml/month for 24-hour diuresis (P=.001), respectively. In the cross-sectional sample taken in January 2010, 17 patients were on the 2 HD sessions/week regimen and 47 were on the 3 HD sessions/week regimen. Serum concentrations of ß2-microglobulin were significantly lower in the 2 HD sessions/week group (19.7 ± 5 vs 38.3 ± 13; P=.000). The mean haemoglobin concentration was similar between the two groups, with a significantly lower dose required of erythropoietin in patients on the 2 HD sessions/week regimen (7058 ± 3749 units/week vs 12 553 ± 10 826 units/week; P=.037). CONCLUSION: In select populations, the start of HD can be administered on a progressively increasing dosage, starting with two sessions/week. In our experience, this is a safe prescription that probably contributes to preserving residual renal function.

Análisis de concordancia entre la bioimpedancia vectorial y la espectroscópica / Analysis of concordance between the bioelectrical impedance vector analysis and the bioelectrical impedance spectroscopy in haemodialysis patients

Introducción: Los valores de los compartimentos corporales proporcionados por los dos sistemas de bioimpedancia más utilizados en España (bioimpedancia de monofrecuencia vectorial [BIVA] y bioimpedancia multifrecuencia espectroscópica [BIS]) son diferentes y no pueden intercambiarse. Objetivo: Analizar si la variabilidad intermétodo es debida a la diferente lectura de las variables bioeléctricas realizadas por los monitores o a las ecuaciones utilizadas por cada uno de ellos para el cálculo de los volúmenes y masas corporales. Otro objetivo fue comprobar si, a pesar de la variabilidad intermétodo, la clasificación de los estados de hidratación definidos por ambos monitores es concordante. Material y métodos: Estudio de corte transversal. En 54 enfermos tratados con hemodiálisis se hizo un análisis de bioimpedancia con los monitores BIVA y BIS inmediatamente antes de una sesión de diálisis. En 38 de ellos se repitió el estudio con el monitor BIVA al finalizar la misma sesión de diálisis. Resultados: Los datos de resistencia y ángulo de fase proporcionados por el monitor BIVA y por el monitor BIS a la frecuencia de 50 kHz son concordantes. En el caso de la resistencia, la variabilidad es de 1,3%, y el coeficiente de correlación intraclase, de 0,99. Para el ángulo de fase, la variabilidad es del 11,5%, y el coeficiente de (..) (AU)

Introduction: The values of body composition provided by the two most commonly used bioelectrical impedance systems in Spain, single-frequency bioelectrical impedance vector analysis (SF-BIVA) and multi-frequency bioelectrical impedance spectroscopy (MF-BIS) are different and not comparable. Objective: Analyse whether the inter-method variability is due to bioelectrical variables measured by the different monitors, or rather due to the equations used to calculate body volume and mass. Another objective was to determine whether, despite the inter-method variability, the classification of hydration status by the two methods is consistent. Material and Methods: Bioelectrical impedance was measured by SF-BIVA and MF-BIS immediately before a dialysis session in 54 patients on haemodialysis. In 38 patients, the study was repeated by SF-BIVA at the end of the same dialysis session. Results: Resistance and phase angle values provided by the two monitors at a frequency of 50kHz were consistent. For resistance, variability was 1.3% and the intra-class correlation coefficient was 0.99. For phase angle, variability and the intra-class correlation coefficient were 11.5% and 0.92, respectively. The volume values (..) (AU)

Analysis of concordance between the bioelectrical impedance vector analysis and the bioelectrical impedance spectroscopy in haemodialysis patients.

INTRODUCTION: The values of body composition provided by the two most commonly used bioelectrical impedance systems in Spain, single-frequency bioelectrical impedance vector analysis (SF-BIVA) and multi-frequency bioelectrical impedance spectroscopy (MF-BIS) are different and not comparable. OBJECTIVE: Analyse whether the inter-method variability is due to bioelectrical variables measured by the different monitors, or rather due to the equations used to calculate body volume and mass. Another objective was to determine whether, despite the inter-method variability, the classification of hydration status by the two methods is consistent. MATERIAL AND METHODS: Bioelectrical impedance was measured by SF-BIVA and MF-BIS immediately before a dialysis session in 54 patients on haemodialysis. In 38 patients, the study was repeated by SF-BIVA at the end of the same dialysis session. RESULTS: Resistance and phase angle values provided by the two monitors at a frequency of 50kHz were consistent. For resistance, variability was 1.3% and the intra-class correlation coefficient was 0.99. For phase angle, variability and the intra-class correlation coefficient were 11.5% and 0.92, respectively. The volume values for total body water, extracellular water, fat mass and body cell mass were biased, with a level of variability that would not be acceptable in clinical practice. The intra-class correlation coefficient also suggested a poor level of agreement. SF-BIVA systems define overhydration or dehydration as a vector below or above the tolerance ellipse of 75% on the longitudinal axis. MF-BIS uses two criteria for pre-dialysis hyper-hydration: overhydration (OH) greater than 2.5 litres, or greater than 15% of extracellular water. The degree of equivalence with the results of the SF-BIVA monitor was better with the second criterion (kappa: 0.81, excellent agreement) than with the first one (kappa: 0.71, acceptable agreement). The MF-BIS system defines post-dialysis normal hydration as a difference between OH and ultrafiltratation volume between ­1.1 and 1.1 litres and agreement with the SF-BIVA system for this parameter was acceptable (weighted kappa index: 0.64). CONCLUSIONS: The MF-BIS and SF-BIVA systems provide similar readings for bioelectrical parameters, and the wide variation in the quantification of volume and body mass must be attributed to the different equations used for calculation. Furthermore, the criteria used by both systems to define both pre- and post-dialysis hydration have an acceptable level of equivalence.