Chronic Kidney Disease-Associated Pruritus and Quality of Life: Learning from Our Patients.

Chronic kidney disease-associated pruritus is itching directly related to kidney disease that cannot be explained by any other condition. Despite technological advances in the different aspects of dialysis sessions and the best treatment for chronic kidney disease patients, it is still a common problem in our patients. The many complex physiological mechanisms involved, the different hypotheses made over the years on the aetiology of the condition, and the great clinical variability may partially explain the limited knowledge about this problem and the difficulties in treating it. The presence of all these factors leads to the persistence of unpleasant symptoms, which must affect the disease burden and quality of life of kidney patients. Through the presentation of an illustrative clinical case, the aim of this review article is to highlight the need for adequate diagnosis and an improved approach to all aspects of chronic kidney disease-associated pruritus, in view of the heavy burden of the disease and the huge impact on the patient's quality of life.

Etiopathogenesis of chronic kidney disease-associated pruritus: putting the pieces of the puzzle together.

Defined as the unpleasant sensation that causes the desire to scratch, pruritus is the most common skin symptom associated with uremia and appears in almost half of patients with advanced chronic kidney disease (CKD). Beyond its direct impact on quality of life, CKD-associated pruritus (CKD-aP) is an independent predictor of mortality that also has a synergistic effect with other quality of life-related symptoms, such as insomnia, depression, and anxiety. Although different mechanisms have been proposed to explain the origin of Pa-ERC, its etiopathogenesis is still not fully understood. Since new therapeutic targets have been identified and several clinical trials have recently shown promising results, our current understanding of the interrelationships has expanded significantly and the pathophysiological mechanisms underlying CKD-aP are now considered to be multifactorial. The potential triggers of pruritus in patients with CKD are discussed in this review, including hypotheses about skin xerosis, accumulation of uremic toxins, dysregulation of the immune system and systemic inflammation, uremic neuropathy, and imbalances in the endogenous opioid system. Other non-uremic causes of pruritus are also discussed, with the aim of guiding the physicians to apply an adequate aetiopathogenic approach to CKD-aP in their day-to-day clinical practice.

Perception of Spanish nephrologists on an old unsolved problem: Pruritus associated with chronic kidney disease (CKD-aP).

INTRODUCTION: Pruritus associated with chronic kidney disease is defined as the sensation of itching, in people with chronic kidney disease, in a one area or all over the body that causes the need to scratch, after having ruled out other dermatological or systemic causes. It is an old and known problem whose prevalence has been able to decrease with the improvement of dialytic techniques but which still persists and is underdiagnosed. OBJECTIVES: The objective of this study was to analyse the current perception of nephrologists about this problem that influences the quality of life of people with chronic kidney disease through a survey. RESULTS: 135 nephrologists, most of them engaged in haemodialysis, participated. 86% considered that pruritus associated with chronic kidney disease is still a problem today that affects the quality of life. Most nephrologists believe that the main pathophysiological cause is uremic toxins (60%) and only 16% believe that it is due to the dysregulation of the opioid system/endorphins-dynorphins. Only 16% comment that the prevalence of pruritus in their centre is greater than 20%. 40% believe that the diagnosis is made because it is manifested by the patient and only 27% because it is asked by the doctor. Moreover, it is not usual to use scales to measure it or the codification in the medical records. The main treatment used is antihistamines (96%), followed by moisturizers/anaesthetics (93%) and modification of the dialysis regimen (70%). CONCLUSIONS: Pruritus associated with chronic kidney disease is still a current problem, it is underdiagnosed, not codified and with a lack of indicated, effective and safe treatments. Nephrologists do not know its real prevalence and the different pathophysiological mechanisms involved in its development. Many therapeutic options are used with very variable results, ignoring their efficacy and applicability at the present time. The new emerging kappa-opioid-receptor agonist agents offer us an opportunity to reevaluate this age-old problem and improve the quality of life for our patients with chronic kidney disease.

Etiopatogenia del prurito asociado a la enfermedad renal crónica: recomponiendo las piezas del puzle / Etiopathogenesis of chronic kidney disease-associated pruritus: Putting the pieces of the puzzle together

Definido como la sensación desagradable que provoca el deseo de rascarse, el prurito es el síntoma cutáneo más frecuente asociado a la uremia, pudiendo aparecer en casi la mitad de los pacientes con enfermedad renal crónica (ERC) avanzada. Más allá de su repercusión directa sobre la calidad de vida, el prurito asociado a la ERC (Pa-ERC) es un predictor independiente de mortalidad que además ejerce un efecto sinérgico con otros síntomas también relacionados con la calidad de vida, como la depresión y el insomnio. Aunque se han propuesto diferentes mecanismos para explicar su origen, la etiopatogenia del Pa-ERC sigue sin conocerse por completo. Dado que se han identificado nuevas dianas terapéuticas y recientemente varios ensayos clínicos han mostrado resultados prometedores, nuestra comprensión actual de las interrelaciones se ha ampliado significativamente, considerando multifactoriales los mecanismos fisiopatológicos subyacentes al Pa-ERC. En la presente revisión se discuten los potenciales factores desencadenantes de prurito en el paciente con ERC, incluyendo las hipótesis sobre la xerosis cutánea, el acúmulo de toxinas urémicas, la desregulación del sistema inmune y la inflamación sistémica, la neuropatía urémica y los desequilibrios en el sistema opioide endógeno, así como otras causas no urémicas de prurito, con el objetivo de orientar al clínico para realizar un adecuado abordaje etiopatogénico del Pa-ERC en su día a día. (AU)

Defined as the unpleasant sensation that causes the desire to scratch, pruritus is the most common skin symptom associated with uremia and appears in almost half of patients with advanced chronic kidney disease (CKD). Beyond its direct impact on quality of life, CKD-associated pruritus (CKD-aP) is an independent predictor of mortality that also has a synergistic effect with other quality of life-related symptoms, such as insomnia, depression, and anxiety. Although different mechanisms have been proposed to explain the origin of Pa-ERC, its etiopathogenesis is still not fully understood. Since new therapeutic targets have been identified and several clinical trials have recently shown promising results, our current understanding of the interrelationships has expanded significantly and the pathophysiological mechanisms underlying CKD-aP are now considered to be multifactorial. The potential triggers of pruritus in patients with CKD are discussed in this review, including hypotheses about skin xerosis, accumulation of uremic toxins, dysregulation of the immune system and systemic inflammation, uremic neuropathy, and imbalances in the endogenous opioid system. Other non-uremic causes of pruritus are also discussed, with the aim of guiding the physicians to apply an adequate etiopathogenic approach to CKD-aP in their day-to-day clinical practice. (AU)

Percepción de los nefrólogos españoles sobre un problema antiguo no resuelto: Prurito asociado a la enfermedad renal crónica (Pa-ERC) / Perception of Spanish nephrologists on an old unsolved problem: Pruritus associated with chronic kidney disease (CKD-aP)

Introducción: El prurito asociado a enfermedad renal crónica se define como la sensación desagradable que provoca la necesidad de rascarse en una parte del cuerpo o en todo en personas con enfermedad renal crónica, tras haberse descartado otras causas dermatológicas o sistémicas. Es un problema antiguo y conocido cuya prevalencia ha podido disminuir con la mejoría de la eficacia dialítica pero que todavía persiste y está infradiagnosticado. Objetivos: El objetivo de este estudio fue analizar la percepción y práctica actual de los nefrólogos sobre este problema que impacta en la calidad de vida de las personas con enfermedad renal crónica a través de una encuesta anónima. Resultados: Participaron 135 nefrólogos, la mayoría dedicados a hemodiálisis. Un 86% consideró que el prurito asociado a enfermedad renal crónica sigue siendo un problema en la actualidad que afecta a la calidad de vida. La mayoría de los nefrólogos opinan que la principal causa fisiopatológica son las toxinas urémicas (60%) y solo un 16% cree que se debe a la desregulación del sistema opioide/endorfinas-dinorfinas. Únicamente un 16% comenta que la prevalencia de prurito en su centro es mayor del 20%. Un 40% cree que el diagnóstico se realiza porque lo manifiesta el paciente y solo un 27% porque lo pregunta el facultativo. Además, no es habitual usar escalas ni codificarlo en la historia clínica. El tratamiento más común son los antihistamínicos (96%), seguido de las cremas hidratantes/anestésicas (93%) y la modificación de la pauta de diálisis (70%). (AU)

Introduction: Pruritus associated with chronic kidney disease is defined as the sensation of itching, in people with chronic kidney disease, in a one area or all over the body that causes the need to scratch, after having ruled out other dermatological or systemic causes. It is an old and known problem whose prevalence has been able to decrease with the improvement of dialytic techniques but which still persists and is underdiagnosed. Objectives: The objective of this study was to analyze the current perception of nephrologists about this problem that influences the quality of life of people with chronic kidney disease through a survey. Results: 135 nephrologists, most of them engaged in hemodialysis, participated. 86% considered that pruritus associated with chronic kidney disease is still a problem today that affects the quality of life. Most nephrologists believe that the main pathophysiological cause is uremic toxins (60%) and only 16% believe that it is due to the dysregulation of the opioid system/endorphins-dynorphins. Only 16% comment that the prevalence of pruritus in their center is greater than 20%. 40% believe that the diagnosis is made because it is manifested by the patient and only 27% because it is asked by the doctor. Moreover, it is not usual to use scales to measure it or the codification in the medical records. The main treatment used is antihistamines (96%), followed by moisturizers/anesthetics (93%) and modification of the dialysis regimen (70%). (AU)

Electronic Patient-Reported Outcomes in Nephrology: Focus on Hemodialysis.

The success of hemodialysis (HD) treatments has been evaluated using objective measures of analytical parameters, or machine-measured parameters, despite having available validated instruments that assess patient perspective. There is an emerging interest regarding the use and relevance of patient-related outcomes (PROs). Electronic PROs (ePROs) involve the use of electronic technology, provide rapid access to this information, and are becoming more widely used in clinical trials and studies to evaluate efficacy and safety. Despite the scarce literature, this review suggests that ePROs are useful in providing a more customized and multidimensional approach to patient management and in making better clinical decisions in relevant aspects such as vascular access, duration and frequency of dialysis sessions, treatment of anemia, mental health, fatigue, and quality of life. The purpose of this review is to raise interest in the systematic use of ePROs in HD and to promote the development of studies in this field, which can respond to the gaps in knowledge and contribute to the implementation of the use of ePROs through new technologies, helping to improve the quality of health care.

Extracellular water/total body water ratio as predictor of mortality in hemodialysis patients.

BACKGROUND: Overhydration is a predictor of mortality in hemodialysis (HD) patients. Bioimpedance spectroscopy (BIS) is used to determine the body composition. Extracellular Water/Total Body Water (ECW/TBW) ratio has been proposed to predict mortality. METHODS: Multicenter, prospective, observational, proof-of-concept study to estimate the impact of ECW/TBW in global and cardiovascular mortality and the relationship with cardiovascular biomarkers. The study included 60 patients (mean age, 71.8 ± 11.4 years; mean time on HD, 52.3 ± 30.8 months) with a median follow-up of 30.5 months (IQ range, 17.2-34 months). RESULTS: Post-dialysis ECW/TBW was directly associated with NT-proBNP and cTnT. During the study 28 patients died, most of them (43%) due to cardiovascular events. Compared to the survivors, these subjects had a higher post-dialysis ECW/TBW ratio (p = 0.006), while for cardiovascular mortality the only significant difference was a higher pre-dialysis ECW/TBW. The ability of post-dialysis ECW/TBW ratio to predict all-cause mortality had an area under the ROC curve (AUC) of 0.71 (CI 95%, 0.57-0.81; p = 0.002), with a cutoff point of 0.5023. For cardiovascular mortality the AUC was 0.66 (CI 95%, 0.52-0.77; p = 0.045), with a cutoff point of 0.4713. CONCLUSIONS: The post-dialysis ECW/TBW ratio measured by BIS can be a predictor of all-cause and cardiovascular mortality.

Inflammation in Diabetic Kidney Disease.

BACKGROUND: Diabetes is a growing public health problem. Diabetic kidney disease (DKD) is the most prevalent chronic renal disease and the major cause of end-stage renal failure worldwide, predominantly due to the increase of Type 2 diabetes associated with obesity. The intimate mechanisms leading to the development and progression of renal injury in DKD are not well understood, but current knowledge indicates that its pathogenesis is multifactorial, where the immune response and inflammation appear to be relevant factors. SUMMARY: This review summarizes the role of relevant inflammatory molecules and pathways that participate in the development of DKD. Likewise, we focused on the new therapeutic approaches based on anti-inflammatory effects of different drugs. Key Messages: This new pathogenic perspective of DKD as an inflammatory condition leads to novel horizons, such as the potential role of inflammatory signaling pathways and their downstream products as emerging biomarkers and promising therapeutic targets.