Contributions to nephrology最新文献

Background: Anemia is a common comorbidity in patients with chronic kidney disease (CKD) and occurs due to diminished renal function. The main cause of such anemia is decreased erythropoietin (EPO) production and secretion from the kidney and a lower erythropoietic response to EPO. Treatment therefore involves erythropoiesis-stimulating agents (ESAs). Optimal erythropoietic response to ESA therapy also requires adequate iron management. However, iron metabolism is also dysregulated in CKD patients.

Summary: During erythropoiesis, biomarkers of iron metabolism are dramatically altered by ESA therapy. Hepcidin 25 is a key hormone of iron metabolism that regulates iron absorption from the gut and the release of stored iron out of reticuloendothelial system cells. Recently, erythroferrone has been identified as an erythroid suppressor of hepcidin 25 production. Because erythroferrone levels are significantly increased by ESA treatment in CKD patients, it may be a key factor in facilitating the release of stored iron into the circulation during erythropoiesis in these patients. In this review, we discuss the characteristics of the important biomarkers of iron metabolism in CKD patients and the changes in these biomarkers after ESA administration. Key Messages: In CKD patients, the management of anemia with ESA therapy requires comprehensive assessment of the levels of various biomarkers, with consideration of their optimal and physiological levels during erythropoiesis.

Background: Recent reports have outlined the present conditions and future prospects of Japanese patients on dialysis. Japan currently has the most rapidly aging population in the world and its dialysis population is also aging rapidly.

Summary: Patients on dialysis in Japan have an extremely good prognosis, probably because of the national health insurance system with efficient introduction of patients to dialysis, creation of a good arteriovenous shunt, an adequate patient education system, management by skilled medical, nursing, and technical staff, and good hygiene. However, although many patients are receiving hemodialysis in Japanese facilities, fewer patients are receiving peritoneal dialysis (PD) or undergoing transplantation. PD is home based, and so offers a high degree of freedom and patient satisfaction, particularly for the elderly. The government is aware of the progress made in the fields of PD and transplantation, and in 2018 revised the reimbursement policy for fees for medical service in accordance with the goal of implementing an "integrated community-based health care system." Key Message: PD is an option for elderly patients and should be considered a strategy for management of renal disease in Japan's super-aging society.

The increase in end-stage renal disease (ESRD) worldwide is of great concern for many countries and has become a worldwide public health problem, which puts a burden on medical healthcare resources. The geographic variation of ESRD has been observed both locally and globally. Greater distance care facilities may impede timely delivery of good quality care and consequently increase the risk of mortality as well as decreased health-related quality of life. Patients living in remote and rural areas could use peritoneal dialysis (PD) as a home-based and economical therapy option. However, morbidity and mortality in PD patients at remote region have been reportedly increasing. Monitoring and managing PD patients living in remote or underserved areas is a big challenge. The establishment and practice of PD satellite center model in China for the management of remote PD patients are a concern for peer professionals across the world. With the support of remote PD center programs, such as the PD satellite center model and telehealth and so on, home PD therapy have further enhanced the PD technology, patient management exercised by quality PD centers, which accordingly benefit more ESRD patients who live in remote areas. Such PD programs can mitigate patients' financial, travel and healthcare pressure and to a certain extent improve the outcomes of these PD patients. Further research is needed to explore more interventions in the management of remote PD patient and better understand the factors that affect the success of these interventions.

Background: The pathogenesis of anemia in chronic kidney disease (CKD) could be multifactorial. In recent animal studies, hepcidin knockout (KO) mice with adenine-induced CKD did not exhibit anemia and iron deficiency. Hepcidin has emerged as a major player in the development of anemia in CKD. We suspected that erythropoietin (EPO) deficiency may not be the mainstay of anemia in CKD, although relative EPO deficiency could contribute to the failure to increase hemoglobin (Hb) levels. Some factors may interfere with the differentiation of erythroids.

Summary: Based on previous flow cytometric analysis, the differentiation and maturation of bone marrow erythroid precursors were compared between 2 mouse models of anemia, namely, EPO-KO mice and adenine-induced CKD mice. EPO-KO mice exhibited greater than 50% reduction in the CD71-low/Ter119-high population, which represents a mature erythroid stage in the bone marrow. In contrast, these mice exhibited no reduction in the CD71-high/Ter119-low and CD71-high/Ter119-high cell populations, which represent an early erythroid stage. However, in CKD mice, the percentages of CD71-high/Ter119-low and CD71-high/Ter119-high erythroid cells, which correspond to proerythroblasts and basophilic erythroblasts, respectively, were decreased in bone marrow. Thus, the CKD mice exhibited a decrease in the number of cells expressing transferrin receptor 1 (TfR1) or early stage erythroblasts, which was completely different from the results obtained for EPO-KO mice. Thus, in CKD, decreased expression of TfR1 in erythroblasts as well as increased hepcidin levels in circulation may hamper erythroblast differentiation by decreasing the iron supply, as iron is an indispensable component of erythroblast differentiation. We conclude that deregulated iron metabolism could be the principal cause of anemia in CKD, impeding the differentiation of erythroblasts. We propose that the "hepcidin-anemia axis" is involved in the pathogenesis of CKD-associated anemia. For the treatment of anemia in CKD, declining hepcidin levels are essential for efficient erythropoiesis. Key Messages: These findings have led us to target the hepcidin-anemia axis as a new treatment strategy for anemia in CKD, including via newly developed erythropoiesis-stimulating agent and hypoxia inducible factor stabilizers.

Background: With the advancement of technology, a dialysis membrane has been developed to achieve the efficient removal of beta-2 microglobulin (β2MG), which could not be removed with previous hemodialysis (HD) membranes. Recently, there has been an increase in the population of elderly chronic kidney disease (CKD) patients with chronic inflammation and malnutrition. The optimal extracorporeal circulation treatment for elderly CKD patients is not certain.

Summary: We have reported the clinical advantages, such as improvements in nutritional, inflammatory, and hemodynamic conditions, of the adsorptive HD membrane for elderly HD patients. We have also reported that the use of β2MG adsorption columns improved the symptoms of dialysis-related amyloidosis and the number of bone cysts, which could not be improved by the high-flux hemodialyzer. Both the adsorptive HD membrane and β2MG adsorption columns remove uremic toxins and inflammatory cytokines via adsorption without aggravating the nutritional condition of these patients. Key Messages: We should reconsider the mechanisms of adsorption, in addition to diffusion and convection, in the extracorporeal circulation treatment of elderly HD patients.

Peritoneal dialysis (PD) is a self-administered chronic renal replacement therapy. It is a home-based therapy, and thus subject to the risk of discrepancy between prescribed dose and effective dialysis delivery. Till now automated peritoneal dialysis (APD) cyclers have recorded the dialysis treatments on a card that patients bring to the hospital for consultation in the PD unit. This card contains the operative parameters of each APD session. Recently, Baxter Healthcare developed a cloud-based tool for remote patient and treatment management. The new platform named Sharesource® embedded into the cycler HOMECHOICE CLARIA® allows to overcome the problems related to poor compliance and feeling of uncertainty by the patient, reducing the number of hospital visits and the workload for physician and nurses of the PD Unit. This new system uploads all treatment information to a secure cloud-based software. The 2-way communication platform gives remote visibility to patient's treatment and allows for feedback and correction of inadequate treatment program. Remote patient management (RPM) allows to visualize the course of home PD day after day, evaluating adherence to prescription, possible alarms during treatment, drainage times, and ultrafiltration amount. The evaluation of all the data can be done by the physician at his desk in the Hospital in front of the computer. RPM allows a patient's dialytic management in real time and enables the nephrologist to remotely modify treatment operative parameters, leaving the patient at home saving kilometers, money and time. In this chapter, we describe a simple algorithm used in our unit to define alarm thresholds and to describe actions to be instituted to correct any possible problem occurring during APD.

Remote monitoring of dialysis offers significant clinical benefits to patients and healthcare providers. However, the collection, transfer, and storage of large amounts of health data involved in remote monitoring require a careful consideration of privacy and data security concerns. Failure to adequately balance clinical utility with privacy has the potential to reduce patients' confidence in remote monitoring and could represent ethical and medicolegal risks for clinicians. We provide 3 case vignettes that illustrate the real-life balance of utility and privacy in patients who received peritoneal dialysis with remote monitoring. We review the principles of health data privacy, confidentiality, and security with respect to remote monitoring as a guide for clinicians.