RESUMEN
BACKGROUND: Chronic kidney disease (CKD) affects around 10% of the global population and has been estimated to affect around 50% of individuals with type 2 diabetes and 50% of those with heart failure. The guideline-recommended approach is to manage with disease-modifying therapies, but real-world data suggest that prescribing rates do not reflect this in practice. OBJECTIVE: To develop a cross-specialty consensus on optimal management of the patient with CKD using a modified Delphi method. DESIGN: An international steering group of experts specialising in internal medicine, endocrinology/diabetology, nephrology and primary care medicine developed 42 statements on aspects of CKD management including identification and screening, risk factors, holistic management, guidelines, cross-specialty alignment and education. Consensus was determined by agreement using an online survey. PARTICIPANTS: The survey was distributed to cardiologists, nephrologists, endocrinologists and primary care physicians across 11 countries. MAIN OUTCOMES AND MEASURES: The threshold for consensus agreement was established a priori by the steering group at 75%. Stopping criteria were defined as a target of 25 responses from each country (N=275), and a 4-week survey period. RESULTS: 274 responses were received in December 2022, 25 responses from Argentina, Australia, Brazil, Guatemala, Mexico, Singapore, South Korea, Taiwan, Thailand, Turkey and 24 responses from Egypt. 53 responses were received from cardiologists, 52 from nephrologists, 55 from endocrinologists and 114 from primary care physicians. 37 statements attained very high agreement (≥90%) and 5 attained high agreement (≥75% and <90%). Strong alignment between roles was seen across the statements, and different levels of experience (2-5 years or 5+ years), some variation was observed between countries. CONCLUSIONS: There is a high degree of consensus regarding aspects of CKD management among healthcare professionals from 11 countries. Based on these strong levels of agreement, the steering group derived 12 key recommendations focused on diagnosis and management of CKD.
Asunto(s)
Diabetes Mellitus Tipo 2 , Nefrología , Insuficiencia Renal Crónica , Humanos , Consenso , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/terapia , Nefrólogos , Nefrología/métodosRESUMEN
Chronic kidney disease (CKD) is a growing global public health problem. The implementation of evidence-based clinical practices only defers the development of kidney failure. Death, transplantation, or dialysis are the consequences of kidney failure, resulting in a significant burden on the health system. Hence, innovative therapeutic strategies are urgently needed due to the limitations of current interventions. Photobiomodulation (PBM), a form of non-thermal light therapy, effectively mitigates mitochondrial dysfunction, reactive oxidative stress, inflammation, and gut microbiota dysbiosis, all of which are inherent in CKD. Preliminary studies suggest the benefits of PBM in multiple diseases, including CKD. Hence, this review will provide a concise summary of the underlying action mechanisms of PBM and its potential therapeutic effects on CKD. Based on the findings, PBM may represent a novel, non-invasive and non-pharmacological therapy for CKD, although more studies are necessary before PBM can be widely recommended.
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Microbioma Gastrointestinal , Terapia por Luz de Baja Intensidad , Insuficiencia Renal Crónica , Disbiosis , Humanos , Inflamación , Diálisis Renal , Insuficiencia Renal Crónica/radioterapiaRESUMEN
Acute kidney injury (AKI) and chronic kidney disease (CKD) are rising in global prevalence and cause significant morbidity for patients. Current treatments are limited to slowing instead of stabilising or reversing disease progression. In this review, we describe mesenchymal stem cells (MSCs) and their constituents, extracellular vesicles (EVs) as being a novel therapeutic for CKD. MSC-derived EVs (MSC-EVs) are membrane-enclosed particles, including exosomes, which carry genetic information that mimics the phenotype of their cell of origin. MSC-EVs deliver their cargo of mRNA, miRNA, cytokines, and growth factors to target cells as a form of paracrine communication. This genetically reprograms pathophysiological pathways, which are upregulated in renal failure. Since the method of exosome preparation significantly affects the quality and function of MSC-exosomes, this review compares the methodologies for isolating exosomes from MSCs and their role in tissue regeneration. More specifically, it summarises the therapeutic efficacy of MSC-EVs in 60 preclinical animal models of AKI and CKD and the cargo of biomolecules they deliver. MSC-EVs promote tubular proliferation and angiogenesis, and inhibit apoptosis, oxidative stress, inflammation, the epithelial-to-mesenchymal transition, and fibrosis, to alleviate AKI and CKD. By reprogramming these pathophysiological pathways, MSC-EVs can slow or even reverse the progression of AKI to CKD, and therefore offer potential to transform clinical practice.
Asunto(s)
Terapia Biológica , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/trasplante , Enfermedades Renales/terapia , Células Madre Mesenquimatosas/metabolismo , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/etiología , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/terapia , Animales , Apoptosis/efectos de los fármacos , Terapia Biológica/métodos , Diferenciación Celular , Proliferación Celular/efectos de los fármacos , Autorrenovación de las Células , Fraccionamiento Químico , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Exosomas/metabolismo , Humanos , Enfermedades Renales/etiología , Enfermedades Renales/patología , Células Madre Mesenquimatosas/citología , Sustancias Protectoras , Insuficiencia Renal/diagnóstico , Insuficiencia Renal/etiología , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/terapiaRESUMEN
OBJECTIVES: Epidemiological and animal studies showed that L-carnitine (LC) supplementation can ameliorate oxidative stress-induced tissues damage. We have previously shown that maternal cigarette smoke exposure (SE) can increase renal oxidative stress in newborn offspring with postnatal kidney underdevelopment and renal dysfunction in adulthood, which were normalised by LC administration in the SE dams during pregnancy. Exposure to an adverse intrauterine environment may lead to alteration in the epigenome, a mechanism by which adverse prenatal conditions increase the susceptibility to chronic disease later in life. The current study aimed to determine whether maternal SE induces epigenetic changes in the offspring's kidney are associated with renal underdevelopment, and the protective effect of maternal LC supplementation. METHOD: Female Balb/c mice (7 weeks) were exposed to cigarette smoke (SE) or air (Sham) for 6 weeks prior to mating, during gestation and lactation. A subgroup of the SE dams received LC via drinking water (SE + LC, 1.5 mmol/L) throughout gestation and lactation. Male offspring were studied at postnatal day (P)1, P20, and 13 weeks. RESULTS: Maternal SE altered the expression of renal development markers glial cell line-derived neurotrophic factor and fibroblast growth factor 2, which were associated with increased renal global DNA methylation and DNA methyltransferase 1 mRNA expression at birth. These disorders were reversed by maternal LC administration. CONCLUSION: The effect of maternal SE on renal underdevelopment involves global epigenetic alterations from birth, which can be prevented by maternal LC supplementation.
Asunto(s)
Carnitina/farmacología , Suplementos Dietéticos , Epigénesis Genética/efectos de los fármacos , Riñón/efectos de los fármacos , Exposición Materna/efectos adversos , Efectos Tardíos de la Exposición Prenatal/prevención & control , Fumar/efectos adversos , Animales , Proliferación Celular/efectos de los fármacos , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Riñón/crecimiento & desarrollo , Riñón/metabolismo , Riñón/patología , Masculino , Metilación/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Estrés Oxidativo/efectos de los fármacos , Embarazo , Efectos Tardíos de la Exposición Prenatal/genética , Efectos Tardíos de la Exposición Prenatal/patología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Transducción de Señal/efectos de los fármacosRESUMEN
To investigate the effect of maternal MitoQ treatment on renal disorders caused by maternal cigarette smoke exposure (SE). We have demonstrated that maternal SE during pregnancy increases the risk of developing chronic kidney disease (CKD) in adult offspring. Mitochondrial oxidative damage contributes to the adverse effects of maternal smoking on renal disorders. MitoQ is a mitochondria-targeted antioxidant that has been shown to protect against oxidative damage-related pathologies in many diseases. Female Balb/c mice (8 weeks) were divided into Sham (exposed to air), SE (exposed to cigarette smoke) and SEMQ (exposed to cigarette smoke with MitoQ supplemented from mating) groups. Kidneys from the mothers were collected when the pups weaned and those from the offspring were collected at 13 weeks. Maternal MitoQ supplementation during gestation and lactation significantly reversed the adverse impact of maternal SE on offspring's body weight, kidney mass and renal pathology. MitoQ administration also significantly reversed the impact of SE on the renal cellular mitochondrial density and renal total reactive oxygen species in both the mothers and their offspring in adulthood. Our results suggested that MitoQ supplementation can mitigate the adverse impact of maternal SE on offspring's renal pathology, renal oxidative stress and mitochondrial density in mice offspring.
Asunto(s)
Suplementos Dietéticos , Riñón/embriología , Riñón/metabolismo , Exposición Materna/efectos adversos , Mitocondrias/metabolismo , Compuestos Organofosforados/farmacología , Estrés Oxidativo , Efectos Tardíos de la Exposición Prenatal , Fumar/efectos adversos , Ubiquinona/análogos & derivados , Animales , Biomarcadores , Femenino , Técnica del Anticuerpo Fluorescente , Mediadores de Inflamación/metabolismo , Masculino , Ratones , Embarazo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Transducción de Señal , Ubiquinona/farmacologíaRESUMEN
Maternal obesity has been shown to increase the risk of obesity and related disorders in the offspring, which has been partially attributed to changes of appetite regulators in the offspring hypothalamus. On the other hand, endoplasmic reticulum (ER) stress and autophagy have been implicated in hypothalamic neuropeptide dysregulation, thus may also play important roles in such transgenerational effect. In this study, we show that offspring born to high-fat diet-fed dams showed significantly increased body weight and glucose intolerance, adiposity and plasma triglyceride level at weaning. Hypothalamic mRNA level of the orexigenic neuropeptide Y (NPY) was increased, while the levels of the anorexigenic pro-opiomelanocortin (POMC), NPY1 receptor (NPY1R) and melanocortin-4 receptor (MC4R) were significantly downregulated. In association, the expression of unfolded protein response (UPR) markers including glucose-regulated protein (GRP)94 and endoplasmic reticulum DNA J domain-containing protein (Erdj)4 was reduced. By contrast, protein levels of autophagy-related genes Atg5 and Atg7, as well as mitophagy marker Parkin, were slightly increased. The administration of 4-phenyl butyrate (PBA), a chemical chaperone of protein folding and UPR activator, in the offspring from postnatal day 4 significantly reduced their body weight, fat deposition, which were in association with increased activating transcription factor (ATF)4, immunoglobulin-binding protein (BiP) and Erdj4 mRNA as well as reduced Parkin, PTEN-induced putative kinase (PINK)1 and dynamin-related protein (Drp)1 protein expression levels. These results suggest that hypothalamic ER stress and mitophagy are among the regulatory factors of offspring metabolic changes due to maternal obesity.
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Dieta Alta en Grasa/efectos adversos , Hipotálamo/metabolismo , Neuropéptido Y/metabolismo , Obesidad/metabolismo , Proopiomelanocortina/metabolismo , Estrés Fisiológico/genética , Animales , Animales Recién Nacidos , Proteína 5 Relacionada con la Autofagia/genética , Proteína 5 Relacionada con la Autofagia/metabolismo , Proteína 7 Relacionada con la Autofagia/genética , Proteína 7 Relacionada con la Autofagia/metabolismo , Femenino , Regulación de la Expresión Génica , Proteínas del Choque Térmico HSP40/genética , Proteínas del Choque Térmico HSP40/metabolismo , Hipotálamo/efectos de los fármacos , Hipotálamo/patología , Fenómenos Fisiologicos Nutricionales Maternos/genética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Neuropéptido Y/genética , Obesidad/etiología , Obesidad/patología , Obesidad/prevención & control , Fenilbutiratos/farmacología , Embarazo , Proopiomelanocortina/genética , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 4/genética , Receptor de Melanocortina Tipo 4/metabolismo , Receptores de Neuropéptido Y/genética , Receptores de Neuropéptido Y/metabolismo , Transducción de Señal , Estrés Fisiológico/efectos de los fármacos , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Respuesta de Proteína Desplegada/efectos de los fármacosRESUMEN
The global nephrology community recognises the need for a cohesive plan to address the problem of chronic kidney disease (CKD). In July, 2016, the International Society of Nephrology hosted a CKD summit of more than 85 people with diverse expertise and professional backgrounds from around the globe. The purpose was to identify and prioritise key activities for the next 5-10 years in the domains of clinical care, research, and advocacy and to create an action plan and performance framework based on ten themes: strengthen CKD surveillance; tackle major risk factors for CKD; reduce acute kidney injury-a special risk factor for CKD; enhance understanding of the genetic causes of CKD; establish better diagnostic methods in CKD; improve understanding of the natural course of CKD; assess and implement established treatment options in patients with CKD; improve management of symptoms and complications of CKD; develop novel therapeutic interventions to slow CKD progression and reduce CKD complications; and increase the quantity and quality of clinical trials in CKD. Each group produced a prioritised list of goals, activities, and a set of key deliverable objectives for each of the themes. The intended users of this action plan are clinicians, patients, scientists, industry partners, governments, and advocacy organisations. Implementation of this integrated comprehensive plan will benefit people who are at risk for or affected by CKD worldwide.
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Manejo de la Enfermedad , Salud Global , Prioridades en Salud , Insuficiencia Renal Crónica/terapia , Lesión Renal Aguda/prevención & control , Ensayos Clínicos como Asunto , Congresos como Asunto , Progresión de la Enfermedad , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Predisposición Genética a la Enfermedad , Humanos , Guías de Práctica Clínica como Asunto , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/etiología , Factores de RiesgoRESUMEN
Maternal cigarette smoke exposure (SE) causes detrimental changes associated with the development of chronic neurological diseases in the offspring as a result of oxidative mitochondrial damage. Maternal L-Carnitine administration has been shown to reduce renal oxidative stress in SE offspring, but its effect in the brain is unknown. Here, we investigated the effects of maternal L-Carnitine supplementation on brain markers of oxidative stress, autophagy, mitophagy and mitochondrial energy producing oxidative phosphorylation (OXPHOS) complexes in SE offspring. Female Balb/c mice (8 weeks) were exposed to cigarette smoke prior to mating, during gestation and lactation with or without L-Carnitine supplementation (1.5 mM in drinking water). In 1 day old male SE offspring, brain mitochondrial damage was suggested by increased mitochondrial fusion and reduced autophagosome markers; whereas at 13 weeks, enhanced brain cell damage was suggested by reduced fission and autophagosome markers, as well as increased apoptosis and DNA fragmentation markers, which were partially reversed by maternal L-Carnitine supplementation. In female SE offspring, enhanced mitochondrial regeneration was suggested by decreased fission and increased fusion markers at day 1. At 13 weeks, there was an increase in brain energy demand, oxidative stress and mitochondrial turnover, reflected by the protein changes of OXPHOS complex, fission and autophagosome markers, as well as the endogenous antioxidant, which were also partially normalized by maternal L-Carnitine supplementation. However, markers of apoptosis and DNA fragmentation were not significantly changed. Thus L-Carnitine supplementation may benefit the brain health of the offspring from smoking mothers.
RESUMEN
Before the introduction of erythropoiesis-stimulating agents (ESAs) in 1989, repeated transfusions given to patients with end-stage renal disease caused iron overload, and the need for supplemental iron was rare. However, with the widespread introduction of ESAs, it was recognized that supplemental iron was necessary to optimize hemoglobin response and allow reduction of the ESA dose for economic reasons and recent concerns about ESA safety. Iron supplementation was also found to be more efficacious via intravenous compared to oral administration, and the use of intravenous iron has escalated in recent years. The safety of various iron compounds has been of theoretical concern due to their potential to induce iron overload, oxidative stress, hypersensitivity reactions, and a permissive environment for infectious processes. Therefore, an expert group was convened to assess the benefits and risks of parenteral iron, and to provide strategies for its optimal use while mitigating the risk for acute reactions and other adverse effects.
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Hipersensibilidad/etiología , Infecciones , Sobrecarga de Hierro , Hierro/administración & dosificación , Hierro/efectos adversos , Estrés Oxidativo , Insuficiencia Renal Crónica/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Ferritinas/sangre , Hematínicos/uso terapéutico , Hemoglobinas/metabolismo , Hepcidinas/sangre , Humanos , Infecciones/sangre , Hierro/sangre , Deficiencias de Hierro , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/inducido químicamente , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapiaRESUMEN
IMPORTANCE: Acute kidney injury (AKI) is characterized by severe loss of glomerular filtration rate (GFR) and is associated with a prolonged intensive care unit (ICU) stay and increased risk of death. No interventions have yet been shown to prevent AKI or preserve GFR in critically ill patients. Evidence from mammalian physiology and small clinical trials suggests higher amino acid intake may protect the kidney from ischemic insults and thus may preserve GFR during critical illness. OBJECTIVE: To determine whether amino acid therapy, achieved through daily intravenous (IV) supplementation with standard amino acids, preserves kidney function in critically ill patients. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, phase II, randomized clinical trial conducted between December 2010 and February 2013 in the ICUs of 16 community and tertiary hospitals in Australia and New Zealand. Participants were adult critically ill patients expected to remain in the study ICU for longer than 2 days. INTERVENTIONS: Random allocation to receive a daily supplement of up to 100 g of IV amino acids or standard care. MAIN OUTCOMES AND MEASURES: Duration of renal dysfunction (primary outcome); estimated GFR (eGFR) derived from creatinine; eGFR derived from cystatin C; urinary output; renal replacement therapy (RRT) use; fluid balance and other measures of renal function. RESULTS: 474 patients were enrolled and randomized (235 to standard care, 239 to IV amino acid therapy). At time of enrollment, patients allocated to receive amino acid therapy had higher APACHE II scores (20.2 ± 6.8 vs. 21.7 ± 7.6, P = 0.02) and more patients had pre-existing renal dysfunction (29/235 vs. 44/239, P = 0.07). Duration of renal dysfunction after enrollment did not differ between groups (mean difference 0.21 AKI days per 10 patient ICU days, 95 % CI -0.27 to 1.04, P = 0.45). Amino acid therapy significantly improved eGFR (treatment group × time interaction, P = 0.004), with an early peak difference of 7.7 mL/min/1.73 m(2) (95 % CI 1.0-14.5 mL/min/1.73 m(2), P = 0.02) on study day 4. Daily urine output was also significantly increased (+300 mL/day, 95 % CI 145-455 mL, P = 0.0002). There was a trend towards increased RRT use in patients receiving amino acid therapy (13/235 vs. 25/239, P = 0.062); however, this trend was not present after controlling for baseline imbalance (P = 0.21). CONCLUSION AND RELEVANCE: Treatment with a daily IV supplement of standard amino acids did not alter our primary outcome, duration of renal dysfunction. TRIAL REGISTRATION: anzctr.org.au Identifier: ACTRN12609001015235.
Asunto(s)
Lesión Renal Aguda/prevención & control , Aminoácidos/uso terapéutico , Enfermedad Crítica/terapia , Anciano , Creatinina/sangre , Cistatina C/sangre , Femenino , Tasa de Filtración Glomerular , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana EdadRESUMEN
Maternal smoking is associated with metabolic disorders, renal underdevelopment, and a predisposition to chronic kidney disease in offspring, yet the underlying mechanisms are unclear. By exposing female Balb/c mice to cigarette smoke for 6 wk premating and during gestation and lactation, we showed that maternal smoke exposure induced glucose intolerance, renal underdevelopment, inflammation, and albuminuria in male offspring. This was associated with increased renal oxidative stress and mitochondrial dysfunction at birth and in adulthood. Importantly, we demonstrated that dietary supplementation of l-carnitine, an amino acid shown to increase antioxidant defenses and mitochondrial function in numerous diseases, in smoke-exposed mothers during pregnancy and lactation significantly reversed the detrimental maternal impacts on kidney pathology in these male offspring. It increased SOD2 and glutathione peroxidase 1, reduced ROS accumulation, and normalized levels of mitochondrial preprotein translocases of the outer membrane, and oxidative phosphorylation complexes I-V in the kidneys of mouse progeny after intrauterine cigarette smoke exposure. These findings support the hypothesis that oxidative stress and mitochondrial dysfunction are closely linked to the adverse effects of maternal smoking on male offspring renal pathology. The results of our study suggest that l-carnitine administration in cigarette smoke-exposed mothers mitigates these deleterious renal consequences.
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Carnitina/farmacología , Exposición Materna/efectos adversos , Mitocondrias/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fumar , Animales , Animales Recién Nacidos , Femenino , Riñón/efectos de los fármacos , Riñón/metabolismo , Masculino , Ratones Endogámicos BALB C , Mitocondrias/metabolismo , Oxidación-Reducción/efectos de los fármacos , Embarazo , Efectos Tardíos de la Exposición Prenatal , Complejo Vitamínico B/farmacologíaRESUMEN
BACKGROUND: Recent clinical practice guidelines have highlighted the importance of advance care planning (ACP) for improving end-of-life care for people with chronic kidney disease (CKD). STUDY DESIGN: We conducted a systematic integrative review of the literature to inform future ACP practice and research in CKD, searching electronic databases in April 2013. Synthesis used narrative methods. SETTING & POPULATION: We focused on adults with a primary diagnosis of CKD in any setting. SELECTION CRITERIA FOR STUDIES: We included studies of any design, quantitative or qualitative. INTERVENTIONS: ACP was defined as any formal means taken to ensure that health professionals and family members are aware of patients' wishes for care in the event they become too unwell to speak for themselves. OUTCOMES: Measures of all kinds were considered of interest. RESULTS: 55 articles met criteria reporting on 51 discrete samples. All patient samples included people with CKD stage 5; 2 also included patients with stage 4. Seven interventions were tested; all were narrowly focused and none was evaluated by comparing wishes for end-of-life care with care received. One intervention demonstrated effects on patient and family outcomes in the form of improved well-being and anxiety following sessions with a peer mentor. Insights from qualitative studies that have not been used to inform interventions include the importance of instilling patient confidence that their advance directives will be enacted and discussing decisions about (dis)continuing dialysis therapy separately from "aggressive" life-sustaining treatments (eg, ventilation). LIMITATIONS: Although quantitative and qualitative findings were integrated according to best practice, methods for this are in their infancy. CONCLUSIONS: Research on ACP in patients with CKD is limited, especially intervention studies. Interventions in CKD should attend to barriers and facilitators at the levels of patient, caregiver, health professional, and system. Intervention studies should measure impact on compliance with patient wishes for end-of-life care.
Asunto(s)
Planificación Anticipada de Atención/organización & administración , Indicadores de Calidad de la Atención de Salud , Insuficiencia Renal Crónica/terapia , Cuidado Terminal/normas , HumanosRESUMEN
Approximately 5-10% of patients with chronic kidney disease demonstrate hyporesponsiveness to erythropoiesis-stimulating agents (ESA), defined as a continued need for greater than 300 IU/kg per week erythropoietin or 1.5 mug/kg per week darbepoetin administered by the subcutaneous route. Such hyporesponsiveness contributes significantly to morbidity, mortality and health-care economic burden in chronic kidney disease and represents an important diagnostic and management challenge. The commonest causes of ESA resistance are non-compliance, absolute or functional iron deficiency and inflammation. It is widely accepted that maintaining adequate iron stores, ideally by administering iron parenterally, is the most important strategy for reducing the requirements for, and enhancing the efficacy of ESA. There have been recent epidemiologic studies linking parenteral iron therapy to an increased risk of infection and atherosclerosis, although other investigations have refuted this. Inflammatory ESA hyporesponsiveness has been reported to be improved by a number of interventions, including the use of biocompatible membranes, ultrapure dialysate, transplant nephrectomy, ascorbic acid therapy, vitamin E supplementation, statins and oxpentifylline administration. Other variably well-established causes of ESA hyporesponsiveness include inadequate dialysis, hyperparathyroidism, nutrient deficiencies (vitamin B12, folate, vitamin C, carnitine), angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, aluminium overload, antibody-mediated pure red cell aplasia, primary bone marrow disorders, myelosuppressive agents, haemoglobinopathies, haemolysis and hypersplenism. This paper reviews the causes of ESA hyporesponsiveness and the clinical evidence for proposed therapeutic interventions. A practical algorithm for approaching the investigation and management of patients with ESA hyporesponsiveness is also provided.