Effects of Rheopheresis in dialysis patients with peripheral artery disease and diabetic foot ulcers: A multicentric Italian study.

BACKGROUND: Peripheral artery disease (PAD) in hemodialysis (HD) patients has a significant social impact due to its prevalence, poor response to standard therapy and dismal prognosis. Rheopheresis is indicated by guidelines for PAD treatment. MATERIALS AND METHODS: Twenty-five HD patients affected by PAD stage IV Lerichè-Fontaine and ischemic ulcer 1C or 2C according to the University of Texas Wound Classification System (UTWCS), without amelioration after traditional medical therapy and/or revascularization, were selected and underwent 12 Rheopheresis sessions in 10 weeks. Improvements in pain symptoms using Numerical Rating Scale (NRS), healing ulcers and laboratory hemorheological parameters have been evaluated. RESULTS: A clinically and statistically significant mean value reduction and of relative percentage differences between estimated marginal means (Δ), calculated at each visits, of NRS was observed, with a maximum value (-48.5%) between the first and last visit. At the end of the treatment period 14.3% of ulcers were completely healed, 46.4% downgraded, 53.6% were stable. Overall, no ulcers upgraded. A statistically significant reduction of the Δ, between the first and last visit, for fibrinogen (-16%) was also observed. CONCLUSION: Rheopheresis reduced overall painful symptoms; data suggest that it could heal or improve ulcers and hemorheological laboratory parameters in HD patients with PAD and ischemic ulcers resistant to standard therapies.

The Next Evolution of HemoDialysis eXpanded: From a Delphi Questionnaire-Based Approach to the Real Life of Italian Dialysis Units.

INTRODUCTION: Impact assessment of new technologies in chronic hemodialysis (HD) is challenging due to HD patient frailty, the complexity of HD clinical trials and practice variability among countries. Among the most recent HD innovations, medium cut-off (MCO) dialyzers present an optimized membrane geometry that provides enhanced clearances for middle and large molecular weight uremic toxins (UT). These toxins are poorly cleared by available HD techniques and largely contribute to patient morbidity and mortality. The aim of this paper is to assess the available clinical evidence about MCO membranes and to identify the next steps needed to generate conclusive data on their use in HD. METHODS: With this purpose, we first reviewed and compared the current HD technologies aimed to improve the clearance of middle and large UT; subsequently, we used a Delphi questionnaire to identify and discuss the consensus about MCO efficacy within a large sample of the Italian Nephrology community. RESULTS AND CONCLUSIONS: Our investigation gathered a significant degree of consensus on the beneficial role of MCO membrane and expanded HD. Finally, we used our results to propose future trial designs and clinical investigations aimed to improve evidence quality about the use of these membranes in the present clinical scenario of dialysis units.

Changes in Cytokines, Haemodynamics and Microcirculation in Patients with Sepsis/Septic Shock Undergoing Continuous Renal Replacement Therapy and Blood Purification with CytoSorb.

BACKGROUND: Extracorporeal blood purification therapies have been proposed as a strategy to remove inflammatory mediators during sepsis, thus improving outcome. OBJECTIVES: We aimed to evaluate changes in cytokines, haemodynamics and microcirculation during blood purification with Cytosorb adsorber in septic patients. METHODS: Prospective observational study on critically ill adult patients with sepsis/septic shock underwent renal replacement therapy (RRT) for acute renal failure and haemoadsorption with Cytosorb as adjunctive therapy for 24 h. Measurements were taken at baseline, after 6 and 24 h: haemodynamic parameters, arterial and central venous blood gases, plasma levels of tumour necrosis factor alpha, interleukin (IL) 1-beta, IL-6, IL-8 and IL-10. The sublingual microcirculation was assessed with sidestream dark field videomicroscopy to evaluate the perfused vessel density (PVD) and microvascular flow quality. Tissue oxygenation and microvascular reactivity were assessed with thenar near infrared spectroscopy (NIRS) with a vascular occlusion test. RESULTS: Nine patients; plasma levels of IL-8 decreased at 24 h (p < 0.05 versus 6 h); no significant variation was found for other cytokines. Haemodynamic remained stable throughout the observation. Microvascular perfusion improved over time, with an increase in PVDs at 6 and 24 h (from 13.9 [13.3-16.4] to 15.7 [15-17.3] and 17 [14.8-18.6] mm/mm2 respectively, p = 0.003) and total vessel densities at 24 h (14.9 [13.9-16.9] vs. 17.9 [15.3-20], p = 0.0015). No significant variation was detected in NIRS-derived parameters. The Sequential Organ Failure Assessment score decreased from 12 ± 3 to 10 ± 1 at 24 h (p = 0.039). CONCLUSIONS: In septic patients undergoing RRT, haemoadsorption with Cytosorb seems to determine a decreasing in plasma levels of IL-8, although levels of other cytokines did not vary significantly, and an improvement of microcirculation despite no significant variation in macro-haemodynamics.

L-carnitine is an osmotic agent suitable for peritoneal dialysis.

Excessive intraperitoneal absorption of glucose during peritoneal dialysis has both local cytotoxic and systemic metabolic effects. Here we evaluate peritoneal dialysis solutions containing L-carnitine, an osmotically active compound that induces fluid flow across the peritoneum. In rats, L-carnitine in the peritoneal cavity had a dose-dependent osmotic effect similar to glucose. Analogous ultrafiltration and small solute transport characteristics were found for dialysates containing 3.86% glucose, equimolar L-carnitine, or combinations of both osmotic agents in mice. About half of the ultrafiltration generated by L-carnitine reflected facilitated water transport by aquaporin-1 (AQP1) water channels of endothelial cells. Nocturnal exchanges with 1.5% glucose and 0.25% L-carnitine in four patients receiving continuous ambulatory peritoneal dialysis were well tolerated and associated with higher net ultrafiltration than that achieved with 2.5% glucose solutions, despite the lower osmolarity of the carnitine-containing solution. Addition of L-carnitine to endothelial cells in culture increased the expression of AQP1, significantly improved viability, and prevented glucose-induced apoptosis. In a standard toxicity test, the addition of L-carnitine to peritoneal dialysis solution improved the viability of L929 fibroblasts. Thus, our studies support the use of L-carnitine as an alternative osmotic agent in peritoneal dialysis.

[Prevention of chronic allograft nephropathy]. / Prevenzione della nefropatia cronica del rene trapiantato.

Chronic allograft nephropathy, characterized by interstitial fibrosis and tubular atrophy, is one of the main causes of allograft failure in the long term. It may be induced by several factors, immunogical or not in nature, which nephrologists must recognize in order to establish the appropriate treatment strategy and prevent progressive loss of graft function. Extensive use of graft biopsy, whether carried out by protocol or suggested by the clinical setting, is recommended for an accurate diagnosis of renal lesions and prompt identification of calcineurin inhibitor-induced toxicity or signs of immunological activity (i.e., subclinical rejection or chronic antibody-mediated rejection) requiring changes of immunosuppressive strategy.

[Kidney transplant: a mere stage of CKD?]. / Il trapianto è uno stato di malattia renale?

At present, renal transplantation is the best treatment for end-stage renal disease but not the cure. The main factors limiting a full recovery after transplantation include the need for lifelong immunosuppressive therapy (which may lead to severe side effects in the long term), and only partial recovery of renal function after grafting. The latter event is not infrequent nowadays due to the increasing age of donors, who frequently die of cerebrovascular accidents and may have subclinical renal vascular lesions despite a GFR >60 mL/min, with increased susceptibility to calcineurin inhibitor toxicity. As a consequence, uremic alterations such as anemia, arterial hypertension and bone disease may persist at various degrees after surgery and affect the patients' outcome in the long term. The outcome of renal transplantation may be improved if, in addition to accurate tuning of immunosuppressive regimens, we take into account the prevention and treatment of all conditions that may impair the clinical course of transplant recipients.

Post-dilution hemodiafiltration with a heparin-grafted polyacrylonitrile membrane.

The aim of this multicenter, prospective study was to explore the possibility of carrying out routine sessions of post-dilution hemodiafiltration with a polyacrylonitrile membrane grafted with heparin (HeprAN) and reduced anticoagulation. Forty-four patients from eight centers were included in the study and treated by means of post-dilution on-line hemodiafiltration with automatic control of TMP, according to three different modalities tested consecutively: phase 1, polyethersulfone filter primed with heparinized saline and anticoagulated with continuous infusion of unfractionated heparin 1000/h; phase 2, HeprAN membrane filter primed with saline without heparin. Anticoagulation: a 1000-unit bolus of unfractionated heparin at the start of session followed by a second one at the end of the second dialysis hour; phase 3, same filter and priming procedure as in phase 2; anticoagulation with nadroparin calcium at the beginning of treatment. Partial or massive clotting of the dialyzer occurred in less than 1% of sessions in phase 1; 10% and 7% in phase 2; and 1% and 2% in phase 3. Clotting limited to the drip chambers was observed in 13%, 34% and 12%, respectively. The study of coagulation parameters showed a better profile when low-molecular weight heparin (LMWH) was used in association with HeprAN membrane, while the generation of TAT complexes did not differ from that observed with the standard anticoagulation modality used in phase 1. Our results suggest that the HeprAN membrane can be used safely in routine post-dilution hemodiafiltration with reduced doses of LMWH.

m-TOR inhibitors may be useful in the treatment of encapsulating peritoneal sclerosis (EPS).

Encapsulating peritoneal sclerosis (EPS) is a rare but serious complication of long-term peritoneal dialysis, often occurring after patients have been shifted to haemodialysis or undergone renal transplantation. EPS is still associated with high morbidity and mortality but, although various treatment modalities have been tried, the optimal therapy is still debated. The present paper reports a 16-year-old patient who developed EPS 6 months after shifting to haemodialysis and, following adhesiolysis, was successfully treated with a combination of steroids, tamoxifen and everolimus, this last drug chosen for its antiproliferative effect through mammalian target of rapamycin (mTOR) inhibition and its ability to block vascular endothelial growth factor and neoangiogenesis. EPS progressively improved and the patient successfully underwent renal transplantation 5 years later. The case suggests that, in view of their mechanism of action, mTOR inhibitors should be considered as an immunosuppressive agent after renal transplantation in patients at risk and merit investigation in future trials on this condition.