Body Composition and Its Clinical Outcome in Maintenance Hemodialysis Patients

Previous epidemiological cohorts demonstrated that higher body mass index (BMI) was associated with greater survival in patients treated by hemodialysis. Although BMI is a simple measure of adiposity in general population, it may be an inaccurate indicator of nutritional status, particularly among dialysis patients given that it does not differentiate between muscle mass and fat as well as body fat distribution. This problem might be aggravated in end-stage renal disease patients because of wasting or edema. In addition, individuals with higher BMI usually have both higher muscle and fat mass than those with lower BMI. Therefore, more sophisticated tool of body composition analysis is needed to address the query of which component is associated with mortality outcome among patients receiving hemodialysis. We summarized the current state of body composition, including lean and fat tissue evaluated by bioelectrical impedance analysis, dual X-ray absorptiometry, computerized tomography, or magnetic resonance imaging, and its association with clinical outcomes among hemodialysis patients. The studies using anthropometry for the estimation of muscle mass, either mid-arm muscle circumference as a proxy of muscle mass or skinfold thickness and waist circumference as a surrogate of body fat and visceral fat, respectively, were all included in this review

High-efficiency Hemodiafiltration

The high mortality of hemodialysis (HD) patients is partly due to the limited capacity of diffusion-based HD to remove large uremic toxins. Hemodiafiltration (HDF) which combines convection with diffusion could enhance both large and protein-bound uremic toxin removal. Recently, there have been several randomized controlled trials demonstrating that high-efficiency post-dilution online HDF could improve survival. Indeed, high blood flow rate, which is the necessary requirement, could not be achieved in some patients. The alternative HDF techniques that could provide comparative efficacy would be considered. Pre-dilution online HDF could be performed without risk of hemoconcentration. Mid-dilution online HDF could be conducted via either simple way by using two dialyzers with the substitution fluid line in between or using special designed dialyzer. Mixed-dilution online HDF requires additional substitution pump for both pre- and post-dilution. There are interesting HDF techniques that could be performed with the conventional HD machine and these include HD with double high-flux, enhanced internal filtration, or super high-flux dialyzers. These modalities enhance the convective clearance in combination with internal backfiltration within the dialyzer in HD platform. All of these alternative high-efficiency HDF modalities are available and can potentially provide quite equivalent benefits with the high-efficiency post-dilution online HDF

Hemodiafiltration in Acute Kidney Injury

Acute kidney injury (AKI) is one of the most important complications during hospitalization, especially in critically ill patients. Recent data demonstrated that certain biomarkers including pro-inflammatory cytokines are associated with high morbidity and mortality. These biomarkers, most of which have middle molecular weight, and protein-bound uremic toxins are limitedly removed by diffusion mechanism in conventional hemodialysis. Hemodiafiltration (HDF), a new modality that combines convective clearance with diffusion, could effectively enhance removal of middle molecule and protein-bound solutes. Therefore, HDF is increasingly used in several AKI settings such as septic AKI, rhabdomyolysis-associated AKI, myeloma cast nephropathy, and contrast-induced AKI. This chapter summarizes the available HDF techniques including intermittent and continuous modes, and clinical data comprise the benefits of HDF on biomarkers and renal as well as cardiovascular outcomes. Additionally, the topic provides the proposed future directions of HDF in various AKI settings

Sepsis-associated Acute Kidney Injury

Sepsis is a life-threatening condition caused by a dysregulated immune response to infection. Interestingly, sepsis mortality increases with acute kidney injury (AKI) and patients with AKI worsen with sepsis. It is interesting to note that most of the clinical trials on sepsis treatment that derived from the results of translational researches are a failure. This is, in part, because of the complexity of human sepsis in comparison with animal models. Another reason for the failure-translation might be the improper matching of the animal models to the individual patient. It is possible that the main mechanism of sepsis induction in each patient with the variety causes of sepsis might be different. Indeed, immune response to sepsis depends on genetic background, route of immune activation, and organisms. Thus, sepsis treatment classified by “mechanistic approach” to individual patient might be more proper than the classification with “sepsis severity”. Specific treatment of sepsis in individual patient according to the specific immune response characteristic might be a more proper translational strategy. Indeed, the understanding in immune response pattern of sepsis and sepsis pathophysiology is necessary for “sepsis mechanistic approach”. Then, we conclude most of the topics and our hypothesis regarding SA-AKI in this review

Neutrophil gelatinase associated lipocalin (NGAL) in leptospirosis acute kidney injury: A multicenter study in Thailand

AKI is one of the most serious complications of leptospirosis, an important zoonosis in the tropics. Recently, NGAL, one of the novel AKI biomarkers, is extensively studied in various specific settings such as sepsis, cardiac surgery, and radiocontrast nephropathy. In this multicenter study, we aimed to study the role of NGAL as an early marker and an outcome predictor of leptospirosis associated AKI. Patients who presented with clinical suspiciousness of leptospirosis were prospectively enrolled in 9 centers from August 2012 to November 2014. The first day of enrollment was the first day of clinical suspicious leptospirosis. Blood and urine samples were serially collected on the first three days and day 7 after enrollment. We used three standard techniques (microscopic agglutination test, direct culture, and PCR technique) to confirm the diagnosis of leptospirosis. KDIGO criteria were used for AKI diagnosis. Recovery was defined as alive and not requiring dialysis during hospitalization or maintaining maximum KDIGO stage at hospital discharge. Of the 221 recruited cases, 113 cases were leptospirosis confirmed cases. Thirty seven percent developed AKI. Median uNGAL and pNGAL levels in those developing AKI were significantly higher than in patients not developing AKI [253.8 (631.4) vs 24.1 (49.6) ng/ml, p < 0.001] and [1,030 (802.5) vs 192.0 (209.0) ng/ml, p < 0.001], respectively. uNGAL and pNGAL levels associated with AKI had AUC-ROC of 0.91, and 0.92, respectively. Both of urine NGAL and pNGAL level between AKI-recovery group and AKI-non recovery were comparable. From this multicenter study, uNGAL and pNGAL provided the promising result to be a marker for leptospirosis associated AKI. However, both of them did not show the potential role to be the predictor of renal recovery in this specific setting

Increasing access to integrated ESKD care as part of Universal Health Coverage

The global nephrology community recognizes the need for a cohesive strategy to address the growing problem of end-stage kidney disease (ESKD). In March 2018, the International Society of Nephrology hosted a summit on integrated ESKD care, including 92 individuals from around the globe with diverse expertise and professional backgrounds. The attendees were from 41 countries, including 16 participants from 11 low- and lower-middle–income countries. The purpose was to develop a strategic plan to improve worldwide access to integrated ESKD care, by identifying and prioritizing key activities across 8 themes: (i) estimates of ESKD burden and treatment coverage, (ii) advocacy, (iii) education and training/workforce, (iv) financing/funding models, (v) ethics, (vi) dialysis, (vii) transplantation, and (viii) conservative care. Action plans with prioritized lists of goals, activities, and key deliverables, and an overarching performance framework were developed for each theme. Examples of these key deliverables include improved data availability, integration of core registry measures and analysis to inform development of health care policy; a framework for advocacy; improved and continued stakeholder engagement; improved workforce training; equitable, efficient, and cost-effective funding models; greater understanding and greater application of ethical principles in practice and policy; definition and application of standards for safe and sustainable dialysis treatment and a set of measurable quality parameters; and integration of dialysis, transplantation, and comprehensive conservative care as ESKD treatment options within the context of overall health priorities. Intended users of the action plans include clinicians, patients and their families, scientists, industry partners, government decision makers, and advocacy organizations. Implementation of this integrated and comprehensive plan is intended to improve quality and access to care and thereby reduce serious health-related suffering of adults and children affected by ESKD worldwide