Depurative capacity toward medium molecules of the dialyzer Toray NV-U® Hydrolink™: A new hydrophilic membrane to perform online hemodiafiltration.

INTRODUCTION: New dialysis membranes with new properties are being developed to improve efficacy and tolerance. The hemocompatibility of a polymeric biomaterial is influenced by the layer of water at the blood membrane interface. The new dialyzer TORAY NV-U® has a membrane Hydrolink™, designed to suppress platelet adhesion and to improve the hemocompatibility. Until now, there is no experience in online hemodiafiltration (OL-HDF).The objective of the present study is to evaluate the efficacy of this new membrane in OL-HDF therapy compared to another membrane commonly used. Other objectives are to evaluate the inflammatory response, hemodynamic tolerance, and the anticoagulation regimes. METHODS: This is a prospective pilot study performed in five anuric patients receiving OL-HDF. For 1 month patients were kept with their usual dialyzer FX1000® (FMC). Subsequently, the dialyzer was changed to TORAY NV-U® (Hydrolink®) for 1 month. In the last dialysis session of each dialyzer, blood tests were performed to evaluate inflammation and depurative capacity. RESULTS: We did not find differences in medium size removal molecules and convective volume: FX1000®: 31 ± 9 l per session and Hydrolink™ 30 ± 8 l; p = 0.7); ß2microglobulin reduction ratio (RR) FX1000® FMC 83 ± 3%; Hydrolink™ 79 ± 4; p = 0.14; Myoglobin RR FX1000® FMC 72 ± 7%; Hydrolink™ 76 ± 4; p = 0.28. We did not find differences in inflammation parameters: serum IL6 with FX1000® 6.0 ± 4.2 pg/mL; Hydrolink™ 7.6 ± 5.0 pg/mL; p = 0.3.During all sessions with the two dialyzers there was adequate plasmatic filling, reaching 85 % filling. All patients had "good" dialyzer status in all dialysis sessions with TORAY NV-U®, while the dialyzer status with FX1000® was "good" in 20% of the sessions, "medium" in 30%, and "dirty" in the remaining 50% dialysis sessions. CONCLUSIONS: The new dialyzer Hydrolink™, TORAY NV-U® is not inferior to perform OL-HDF compared to dialyzers usually used for this therapy, and could allow decrease heparin doses. Further studies with a bigger sample size and longer follow-up will answer if Hydrolink improves inflammation and assess a better hemodynamic tolerance.

Body composition and ventricular function in hemodialysis patients.

There is no evidence about the potential role of body composition on cardiovascular mortality in dialysis patients. The aim of this study was to assess the relationship between body composition and changes in ventricular function. We conducted an observational study over a population of 78 patients on chronic hemodialysis. A transthoracic echocardiogram and a bioimpedance were performed at the beginning and at the end of the study. The mean follow-up time was 30.6 months. Patients who had a higher fat tissue index (FTI > 9.20 kg/m2 ) experienced a worsening in right and left ventricular function. They developed a greater fall in tricuspid annular plane systolic excursion (TAPSE) (-1 ± 4.3 mm) and left ventricular ejection fraction (LVEF)(-4.2 ± 6.8%), compared to those with lower FTI (p = 0.032 and p = 0.045, respectively). No associations were found between any other echocardiography or body composition parameters and overall mortality. Patients with right ventricular dysfunction (determined as TAPSE) experienced a tendency to higher mortality rate along the study (HR for mortality of 13.5 (95% CI, 1.1-166.7; p = 0.041)]. A higher fat tissue index could be associated with a deleterious effect over right and left ventricular function in dialysis patients.

Thrombotic Microangiopathy in a Kidney Transplant Patient With COVID-19.

Kidney transplant recipients are at increased risk for infection, including coronavirus disease 2019 (COVID-19), given ongoing immunosuppression. In individuals with COVID-19, complications including thrombosis and endothelial dysfunction portend worse outcomes. In this report, we describe a kidney transplant recipient who developed severe thrombotic microangiopathy with a low platelet count (12 ×109/L), anemia (hemoglobin, 7.5 g/dL with 7% schistocytes on peripheral-blood smear), and severe acute kidney injury concurrent with COVID-19. The clinical course improved after plasma exchange. Given this presentation, we hypothesize that COVID-19 triggered thrombotic microangiopathy.

COVID-19: clinical course and outcomes of 36 hemodialysis patients in Spain.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia emerged in Wuhan, China in December 2019. Unfortunately, there is a lack of evidence about the optimal management of novel coronavirus disease 2019 (COVID-19), and even less is available in patients on maintenance hemodialysis therapy than in the general population. In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of all maintenance hemodialysis patients hospitalized with COVID-19 from March 12th to April 10th, 2020 as confirmed by real-time polymerase chain reaction. Baseline features, clinical course, laboratory data, and different therapies were compared between survivors and nonsurvivors to identify risk factors associated with mortality. Among the 36 patients, 11 (30.5%) died, and 7 were able to be discharged within the observation period. Clinical and radiological evolution during the first week of admission were predictive of mortality. Among the 36 patients, 18 had worsening of their clinical status, as defined by severe hypoxia with oxygen therapy requirements greater than 4 L/min and radiological worsening. Significantly, 11 of those 18 patients (61.1%) died. None of the classical cardiovascular risk factors in the general population were associated with higher mortality. Compared to survivors, nonsurvivors had significantly longer dialysis vintage, increased lactate dehydrogenase (490 U/l ± 120 U/l vs. 281 U/l ± 151 U/l, P = 0.008) and C-reactive protein levels (18.3 mg/dl ± 13.7 mg/dl vs. 8.1 mg/dl ± 8.1 mg/dl, P = 0.021), and a lower lymphocyte count (0.38 ×103/µl ± 0.14 ×103/µl vs. 0.76 ×103/µl ± 0.48 ×103/µl, P = 0.04) 1 week after clinical onset. Thus, the mortality among hospitalized hemodialysis patients diagnosed with COVID-19 is high. Certain laboratory tests can be used to predict a worsening clinical course.