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Elderly individuals with chronic disorders tend to develop inflammaging, a condition associated with elevated levels of blood inflammatory markers, and increased susceptibility to chronic disease progression. Native and adaptive immunity are both involved in immune system senescence, kidney fibrosis and aging. The innate immune system is characterized by a limited number of receptors, constantly challenged by self and non-self stimuli. Circulating and kidney resident myeloid and lymphoid cells are all equipped with pattern recognition receptors (PRRs). Recent reports on PRRs show kidney overexpression of toll-like receptors (TLRs) in inflammaging autoimmune renal diseases, vasculitis, acute kidney injury and kidney transplant rejection. TLR upregulation leads to proinflammatory cytokine induction, fibrosis, and chronic kidney disease progression. TLR2 blockade in a murine model of renal ischemia reperfusion injury prevented the escape of natural killer cells and neutrophils by inflammaging kidney injury. Tumor necrosis factor-α blockade in endothelial cells with senescence-associated secretory phenotype significantly reduced interleukin-6 release. These findings should encourage experimental and translational clinical trials aimed at modulating renal inflammaging by native immunity blockade.

We report a preliminary experience of adjuvant therapy with Hemoperfusion (HP) in patients with Severe Acute Respiratory Syndrome-CoronaVirus 2 (SARS-CoV2) pneumonia. Currently, there are no approved treatments for CoronaVirus Disease 19 (COVID-19); however, therapeutic strategies based on the preclinical evidence include supportive measures, such as oxygen supplementation, antiviral, and anticoagulant agents. Despite these treatments, 10% of patients worsen and develop severe acute respiratory distress syndrome (ARDS). Since the pathogenic mechanism of ARDS is an uncontrolled inflammatory state, we speculate that removing inflammation effectors from blood may contrast tissue injury and improve clinical outcome. In a scenario of dramatic medical emergency, we conducted an observational study on 9 consecutive patients hospitalized in COVID Intensive Care Unit, where 5 of 9 consecutive patients were treated with HP, due to the emergency overload made it impossible to deliver blood purification in the other 4 patients. COVID-19 was diagnosed through the identification of virus sequences by reverse transcription-PCR on respiratory specimens. All patients had severe pneumonia requiring continuous positive airway pressure. HP was started in all patients 6–7 days after hospital admission. The treated patients (T) received 2 consecutive sessions of HP using CytoSorb cartridge. Our results show a better clinical course of T compared to control patients (C), in fact all T except 1 survived, and only 2 of them were intubated, while all C required intubation and died. Lymphocytopenia worsened in C but not in T. C-reactive protein decreased in both patients, but to a greater extent in T. IL-6, IL-8, and TNF-α decreased after HP, IL-10 did not change. Respiratory function remained stable and did not worsen in T compared to C. The limited sample size and observational study design preclude a sound statement about the potential effectiveness of HP in COVID-19 patients, but our experience suggests a potential therapeutic role of adjuvant CytoSorb HP in the early course of CO­VID-19 pneumonia. A randomized clinical trial is ongoing.

Introduction: Acute kidney injury (AKI) is a common complication among hospitalized patients, potentially affecting short- and long-term clinical outcomes. In this retrospective study, we evaluated renal outcomes in noncritically ill patients who required acute hemodialysis (HD) because of an AKI episode occurring during hospitalization. Methods: Sixty-three hemodynamically stable patients with AKI undergoing acute intermittent HD were included. Kidney function was evaluated at baseline control (pre-AKI), at AKI diagnosis and during the follow-up. According to serum creatinine and the estimated glomerular filtration rate (eGFR), we defined three clinical conditions: renal recovery, different stages of acute kidney disease (AKD), and chronic kidney disease (CKD). Results: Among the 63 patients evaluated, 34 patients (54%) had a history of CKD. Six patients (10%) presented early full renal recovery. HD treatment was stopped in 38 patients (60%), while 25 patients (40%) required maintenance HD. Dialysis-independent patients presented lower comorbidity and higher baseline eGFR and delta creatinine, compared to dialysis-dependent patients. Baseline CKD, previous AKI episodes, and parenchymal causes of AKI were associated with a significant risk of dialysis dependence. At 1-month control, 15 patients (39%) presented AKD stage 0, 6 patients (16%) AKD stage 1, and 17 patients (44%) AKD stage 2–3. At 3-month control, 29 out of 38 patients recovering from AKI (76%) presented CKD. AKD stage was significantly correlated with the risk of CKD development, which, resulted higher in patients with lower baseline eGFR. Conclusions: AKI might represent a risk factor for the development of chronic kidney damage, even in noncritically ill patients.

Background and Aims Chronic antibody-mediated rejection (cABMR) is the main cause of kidney allograft failure. Currently there is no effective treatment. Extracorporeal photopheresis (ECP) is an immunomodulating therapy that acts increasing regulatory T cells and reducing effector T cells. ECP has been used with success to treat heart and lung rejection, acute and chronic Graft versus Host Disease and few cases of acute antibody mediated kidney rejection. The aim of this study was to describe the preliminary experience of ECP use to treat kidney cABMR. Method This is an ongoing prospective observational study approved by the ethical committee of our institution. The study started in 2017 on kidney transplant recipients (KTR) with cABMR diagnosis bioptically proved. All patients received ECP in addition to the standard treatment. ECP schedule is reported in Figure 1. Serum and urine samples were collected at the beginning of the study and every 6 months during the follow up period. Analyzed variables were: glomerular filtration rate (GFR), urine albumin-creatinine ratio (UACR), Donor Specific Antibodies (DSA) measeured as Mean Intensity Fluorescence (MIF) by Luminex. Collected clinical data included: death, hospital admission number, cancer diagnosis, infections. Quality of life (QoL) scale was also recorded. Results We enrolled 6 KTR equally distributed in gender (3 M, 3 F) and aged 49.16 ± 7.15 years (mean±ds) . Median follow up time was 12 months (min 12 – max 36). All KTR had both class I and class II DSA with MFI > 5000 (min 5000 – max 36780). In all patients no GFR deterioration was observed during follow up. UACR improved in 3 KTR while remained stable in the other 3 patients. No deaths or infections or cancer diagnosis or hospital admissions occurred. QoL ameliorated in all KTR. DSA MIF decreased in all KTR and in 3 of them became even negative after 12 months of treatment. Conclusion ECP is a safe and effective treatment to slow down the deterioration of kidney function in cABMR patients. Further studies are necessary to identify the responder patients and to better tailor the treatment schedule.

Background and Aims Adenosine (Ado), the main substrate of ATP, is a potent endogenous anti-inflammatory nucleoside. Hypoxia induces ATP depletion, AMP extracellular increase that is phosphohydrolyzed to ADO by the enzyme ecto-5′-nucleotidase (CD73). Constitutive CD73 expression is higher in deep cortex outer medulla that is the most vulnerable region to ischemic injury. Notably CD73 is also expressed on Mesenchymal Stromal Cell (MSC) and is essential phenotypic marker. Previously in a rat model of Donation after Circulatory Death (DCD), we demonstrated that the perfusion of ischemic kidney with MSC or MSC derived Extracellular Vesicles (EV) protects tissue up regulating mitochondrial energetic metabolism genes. The aim of this study was to investigate the role of CD73/Ado system in MSC/EV protection from ischemia. Method Fisher rats were used as kidney donors and Lewis rats as MSC donors. MSC missing CD73 were produced by electroporation in the presence of specific siRNA to block CD73 expression (siMSC). EV were isolated from supernatants of MSC and siMSC (siEV) medium through differential ultracentrifugations. Size distribution and enumeration analysis were performed using NanoSight NS300. EV phenotypic characterization was performed in flow cytometer using CD45, CD49e, CD63, CD9, CD81 and CD73 monoclonal antibodies. DCD model was obtained by renal artery clamping for 20 minutes. This warm ischemia time represents the “no touch period” imposed by the Italian law to death declaration. After nephrectomy, kidneys were perfused in hypothermia (4°C) with Belzer Solution (BS), or BS supplemented with 3x106 MSC (MSC) or BS supplemented with 28,5x109 EV/siEV (EV/siEV). The effluent fluid (EF) was collected at the beginning (T0), every hours (T1, T2, T3) and at the end of the perfusion (T4). Ado and ATP determinations in EF and tissues were performed by HPLC and ELISA, respectively. Results EF Ado was significantly higher in MSC vs BS from T1 and in EV vs BS from T0 to T4 (p Conclusion CD73 expressed on MSC /EV impacts on cell energy metabolism pathway and ATP generation. This is the first evidence that MSC/EV act through CD73/Ado system to prevent ischaemic damage.

Although mushroom poisoning is a rare cause of acute renal injury, in some cases it may lead to the development of a severe and irreversible renal failure. Orellanus syndrome is the most important example of organic renal damage related to mushroom consumption. It is caused by the ingestion of orellanine, the main toxin of different types of Cortinarius mushrooms (Cortinarius speciosissimus, C. orellanus, C. orellanoides, etc.), and it is characterized by progressive clinical phases with a predominant kidney involvement, finally requiring renal replacement therapy in about 10% of cases. Renal damage is often late and associated with a histological picture of interstitial nephritis. Diagnosis is essentially clinical and no specific therapy has been shown to be effective in preventing and treating renal damage. Here, we describe the case of a patient with mixed wild mushroom poisoning, presenting the typical clinical signs and course of the Orellanus syndrome. This case offers us the opportunity to review the main clinical features of this severe and little-known intoxication.

Toll-like receptor 4 (TLR4) promotes inflammation in hemodialysis patients (HD). A soluble form of extracellular TLR4 (sTLR4) has been recently characterized, which showed the ability to attenuate TLR4 signalling. In this study, we describe the sTLR4 profile in regular HD patients.In a cross-sectional study we enrolled forty prevalent HD patients (68.2 ± 16.3 years, twenty-five males) with a median dialysis vintage of 41 months. Nineteen patients were undergoing standard bicarbonate HD (BHD) and 21 patients on-line hemodiafiltration (HDF). Ten healthy sex-matched subjects constituted the controls (C).Before and after the HD session, serum was tested for sTLR4 levels by ELISA. Moreover, clinical and biochemical data were collected, including body mass index, albumin, and C-reactive protein (CRP) levels. Body composition was expressed as a 3-compartment model, providing lean tissue index and fat tissue index (FTI).Describe the profile of sTLR4 in HD patients, evaluating the correlations among sTLR4 levels and the main clinical characteristics, inflammatory and nutritional parameters.Patients with subclinical inflammation (i.e., high CRP levels without clinical symptomatology) presented higher sTLR4 levels (0.42 ± 0.25 ng/mL) with respect to both C and not inflamed HD patients (0.23 ± 0.19 ng/mL, P .05). There was a significant direct correlation between predialysis sTLR4 and body mass index, FTI (r = 0.55), and CRP levels (r = 0.52) and inverse correlation with lean tissue index and albumin (r = -0.4). In multivariate analysis, sTLR4 resulted directly associated with FTI (P = .038). Notably, sTLR4 levels resulted higher in bicarbonate hemodialysis versus hemodiafiltration (0.37 ± 0.18 vs. 0.19 ± 0.21 ng/mL, P .05).sTLR4 correlates with inflammatory and nutritional parameters, presenting as a new potential player in modulating subclinical inflammation in HD patients.

Hepatocyte growth factor (HGF) is a pleiotropic cytokine which exerts a variety of effects on several cells, being involved in the regulation of many biological processes, such as inflammation, tissue repair, morphogenesis, angiogenesis, tumour propagation, immunomodulation of viral infections and cardio-metabolic activities. Patients undergoing regular hemodialysis (HD) present elevated levels of HGF, mainly due to the leukocyte activation associated with HD treatment. High HGF levels might account for specific clinical features of HD patients, i.e. mild liver damage in course of HCV-infection and high cardiovascular risk profile. Moreover, in patients with acute kidney injury, the induction of HGF may represent a crucial step to promote renal recovery, which can have important prognostic consequences in the short and long-term. In this review we discuss the mechanisms underlying HGF production in HD patients, the role of HGF in this particular patient population and the potential clinical implications derived from the study of HGF in HD patients.

Objective Advanced glycation end-products (AGEs) are proposed to influence inflammatory pathways and cardiovascular risk in chronic kidney disease (CKD). Dietary AGEs are believed to sustain circulating levels and toxicity in this condition. Design and Patients We investigated this aspect in a cross-sectional pilot study measuring levels of the AGE marker carboxymethyl lysine (CML) and fluorescent AGEs in the blood of pre-dialysis patients with CKD and hemodialysis (HD) patients (n = 10 each), and in a group of matched healthy controls (Ctr). Methods Plasma CML was measured by immuno-dot blot and fluorescent AGEs were determined by high-performace liquid chromatography (HPLC) analysis measuring the fluorescence of the cross-link pentosidine. The dietary intake of CML was assessed by dietary recall to trace total AGE intake in patients with CKD and the Ctr group. All the subjects included in the study were assessed for dietary intake while maintaining their usual diet. Main exclusion criteria for patients with CKD and HD were severe protein-caloric malnutrition and inflammation (measured by high sensitivity C-reactive protein and interleukin-6 levels). Results Plasma CML, as well as free and protein-bound fluorescent AGEs, significantly increased in CKD and even more in HD patients than that of the Ctr group. In patients with CKD, the average dietary intake of CML was less than half than that of the Ctr group (6 vs. 13 MU/day) and the lowered protein intake adopted spontaneously by these patients appear to explain this finding. Conclusions The results show that the intake of CML does not affect circulating levels of this as well as of other AGEs, in well nourished predialysis CKD patients.

While sirolimus (SRL) is thought to be a non-nephrotoxic agent, cyclosporine A (CsA) toxicity is a serious problem in kidney transplantation. We compared the effects of the two drugs on T-helper (Th) subsets in kidney transplant patients. We examined 24 first cadaver kidney recipients equally randomized to receive SRL/mycophenolate mofetil (MMF)/methylprednisolone (MP), or cyclosporine with either MMF or MP. The Th1 and Th2 subsets in peripheral blood were separated based on their production of interferon-gamma (INFgamma) or interleukin (IL)-4/IL-5. The lymphocytes were stimulated with phytohemoagglutinin or with allogenic CD3-depeted and irradiated antigen-presenting cells. Furthermore, the conversion potential of Th0 to Th1 was determined by measuring IL-12 and IL-18 levels after lipopolysaccharide challenge. When peripheral blood lymphocytes taken from SRL-treated patients were stimulated by phytohemoagglutinin, there were significantly lower INFgamma-producing cells compared with the lymphocytes taken from patients treated with CsA. The number of IL-4/IL-5-producing cells did not differ among the patient groups. Release of IL-12 but not IL-18 from peripheral lymphocytes following treatment with lipopolysaccharide was significantly lower in the SRL-treated patients. These results show that compared with CsA, SRL caused a significant decrease in the Th1 lymphocyte subset associated with a significant reduction of IL-12 release.

Macrophage-stimulating protein (MSP) is a scatter factor that causes cell proliferation and migration, and receptor origin nantaise (RON) is its receptor. RON is expressed in macrophages and mesangial cells, and MSP is produced by renal tubular cells. This study investigated whether MSP/RON participate in the pathogenesis of anti-Thy 1 nephritis, a glomerular disease that is characterized by invasion of circulating monocytes into glomeruli and migration and proliferation of mesangial cells. In vivo, renal function and histopathology were studied in rats that had anti-Thy 1 disease and were untreated and treated with a neutralizing anti-MSP antibody. In vitro, whether monocytes express RON and whether MSP has a chemotactic effect on monocytes were studied. In vivo, in anti-Thy 1 disease, MSP was expressed de novo in glomeruli, and neutralization of MSP attenuated the rise in serum creatinine and proteinuria, stopped glomerular neutrophil and monocyte influx, protected from glomerular injury, and lessened mesangial cell overgrowth. In vitro, unstimulated monocytes did not express RON, but the stimulation with LPS induced de novo RON expression. LPS-stimulated monocytes were attracted by MSP. These results demonstrate a pathogenic role of the MSP/RON system in anti-Thy 1 nephritis.

Progressive hemodialysis is based on the simple idea of adjusting its dose according to residual renal function (RRF). The progressive, infrequent paradigm is slowly gaining a foothold among nephrologists, despite a lot of skepticism in the scientific world. Given the importance of RRF preservation in conservative therapy, it seems a contradiction to ignore the contribution of RRF when patients initiate hemodialysis (HD), especially when it is routinely considered with peritoneal dialysis. While a three-times-weekly HD regimen is broadly considered the standard starting regimen for new patients, twice-weekly HD has been used in selected patients and is currently a common practice in South-East Asia. Small studies indicate that a once-weekly HD regimen may be a viable starting option as well. Progressive hemodialysis still requires validation, yet it is promising. We share the belief that a randomized clinical trial to investigate progressive hemodialysis is much needed, but we also strongly recommend including a once-weekly HD starting dose as part of any such investigation.

Since the early description of Randall plaques in 1937, studies of the pathogenesis of stone formation mainly focused on the chemistry involving salt precipitation and crystallization, rather than tubular and interstitial medullar mechanisms of calcium concentration and supersaturation. In 2003, Bushinsky published a suggestive and inspiring sequence of events aimed to show that the basement membrane of the thin limb of the loop of Henle can be the first site of nucleation, as recently shown by the impressive work by Evan et al. The aim of this minireview is to verify the consistency of the Evan and Bushinsky theory with the current literature in the field.

T-helper (Th) lymphocytes consist of Th1 and Th2 subsets. Th1 cells are effectors of cell-mediated immunity and secrete interferon-gamma (IFN-gamma), which recruits new Th1 cells in cooperation with interleukin-12 (IL-12; produced by monocytes) and inhibits Th2 differentiation. Th2 cells produce IL-4 and IL-10, which inhibit IFN-gamma secretion and cell immunity. We investigated whether the impaired immune response in uremia is associated with an altered balance of Th1/Th2. Peripheral-blood mononuclear cells (PBMCs) were collected from patients with chronic renal failure (CRF) on conservative treatment (CRF patients), patients with end-stage renal disease (ESRD) on regular hemodialysis therapy (ESRD-HD patients), and healthy controls (CON). CD4(+) cells were isolated from PBMCs by negative selection using a magnetic labeling system. PBMCs and purified CD4(+) cells were cultured in Iscove's medium and Iscove's medium plus mitogens (phytohemagglutinin and lipopolysaccharide). IFN-gamma, IL-12, IL-4, and IL-10 were measured in supernatant. The constitutive release of IL-4 and IL-10 by PBMCs and CD4(+) cells of CRF and ESRD-HD patients was increased by five to eight times in comparison with CON (P < 0.001). Constitutive IFN-gamma release by PBMCs of ESRD-HD patients was undetectable, although they secreted an increased amount of IL-12. Mitogen-stimulated release of IFN-gamma by PBMCs and CD4(+) cells of CRF and ESRD-HD patients was blunted (average PBMCs: CON, 115.8 pg/2 x10(6) cells; CRF, 81.8 pg/2 x10(6) cells; ESRD-HD, 9.3 pg/2 x10(6) cells; CD4(+) cells: CON, 358.0 pg/5 x 10(5) cells; CRF, 165.4 pg/5 x 10(5) cells; ESRD-HD, 43.5 pg/5 x 10(5) cells). The ability of PBMCs of ESRD-HD patients to secrete IFN-gamma was recovered after IL-4 and IL-10 neutralization. Uremia is associated with a prevalence of Th1 over Th2 cells and a configuration of cytokine network that depresses cell-mediated immunity.

Sibutramine, a serotonin reuptake inhibitor, currently is used in treatment of obesity. The known side effects of sibutramine, ie, hypertension and tachycardia, depend on its adrenergic and serotoninergic effects. We describe a case of life-threatening hyponatremia associated with sibutramine use in an obese woman. We hypothesize that sibutramine, through its effect on neurotransmitters, may induce antidiuretic hormone secretion and lead to a syndrome of inappropriate antidiuretic hormone secretion. We advise careful monitoring of water-electrolytic balance during sibutramine therapy.

Background It is important to ensure an adequate sodium and volume balance in neurosurgical patients in order to avoid the worsening of brain injury. Indeed, hyponatremia and polyuria, that are frequent in this patient population, are potentially harmful, especially if not promptly recognized. Differential diagnosis is often challenging, including disorders, which, in view of similar clinical pictures, present very different pathophysiological bases, such as syndrome of inappropriate antidiuresis, cerebral/renal salt wasting syndrome and diabetes insipidus. Case presentation Here we present the clinical report of a 67-year-old man with a recent episode of acute subarachnoid haemorrhage, admitted to our ward because of severe hyponatremia, hypokalemia and huge polyuria. We performed a complete workup to identify the underlying causes of these alterations and found a complex picture of salt wasting syndrome associated to primary polydipsia. The appropriate diagnosis allowed us to correct the patient hydro-electrolyte balance. Conclusion The comprehension of the pathophysiological mechanisms is essential to adequately recognize and treat hydro-electrolyte disorders, also solving the most complex clinical problems.

Background. Elevated plasma levels of cytokines have been associated with an increased risk of congestive heart failure (CHF) even in people without history of myocardial infarction. Here we have tested the hypothesis that effective removal of pro-inflammatory cytokines in patients with advanced CHF unresponsive to diuretic treatment is associated with diuresis restoration and with a significant reduction of B-type natriuretic peptide (BNP) circulating levels. Methods. We prospectively enrolled 10 patients with decompensated CHF (NYHA classes III–IV). Five patients unresponsive to diuretic treatment underwent a short course of intermittent haemodiafiltration (iHDF), whereas five patients responsive to diuretics were treated with intravenous boluses of furosemide. Renal function was similar between the two groups. Results. Excess body fluids were removed in both groups always resulting in a reduction of pulmonary congestion and peripheral oedema. NYHA class improved in all patients, but one treated by intravenous boluses of furosemide. Only patients treated with iHDF showed a significant reduction of circulating interleukin-8 and monocyte chemoattractant protein-1. After the end of iHDF treatment, patients showed consistent restoration of diuretic responsiveness to significantly lower doses of oral furosemide up to one month of follow-up. Plasma levels of BNP before treatment were significantly higher in the iHDF group, lowering significantly in both groups after treatment. Conclusions. Our results suggest that HDF is an effective treatment for patients with advanced CHF when cytokines have to be cleared and diuretic responsiveness needs to be restored. In our experience, iHDF is a cost-effective option when compared with continuous ultrafiltration methods because it can be performed in a routine dialysis unit without adjunctive costs for machinery or personnel training.

Vitamin E–loaded dialyzer resets PBMC-operated cytokine network in dialysis patients.BackgroundIn hemodialysis patients the activity of stimulated Th1 lymphocytes is depressed, while Th2 cells are constitutively primed. Such phenomena may depend on monocyte activation and altered release of interleukin (IL)-12 and IL-18, which regulate Th cell differentiation. Reactive oxygen species (ROS) activate monocytes; therefore, a hemodialyzer with antioxidant activity would contrast ROS, prevent monocyte activation, reset IL-12 and IL-18 release, and restore Th1/Th2 balance.MethodsTen patients on regular dialysis treatment (RDT) with cellulosic membrane (CM) were shifted to vitamin E–coated dialyzer (VE). During treatment with CM and after 3, 6, and 12months of treatment with VE, peripheral blood mononuclear cells (PBMC) and purified CD4+ cells were isolated, and cultured, resting, mitogen-stimulated, and interferon γ (IFNγ), IL-4, IL-10, IL-12, and IL-18 release was measured. Vitamin E and A plasma levels and the effects of a single dialysis session on peripheral blood NO levels were assayed.ResultsThe constitutive release of IL-4 and IL-10 by CD4+ cells was abated significantly by treatment with VE (nadir -77.8% and -55.3%, respectively, at 12months). INFγ release by mitogen-stimulated CD4+ recovered with VE (zenith +501% at 12months). PBMC constitutive production of IL-12 and IL-18 was significantly reduced by VE (nadir at 12months -64.7% and -51.3%, respectively). VE increased plasma levels of vitamins E and A. NO plasma levels fell after a single dialysis treatment with VE (-17%, P < 0.05) in contrast with CU (+27.1%, P < 0.05).ConclusionThe network of cytokines released by monocytes and Th cells is reset toward normality by treatment with vitamin E–coated dialyzer.

To the Editor: The risk for vascular disease is much higher in hemodialysis patients than in the general population [1]. Sex, hypertension, diabetes mellitus, being overweight, hyperlipidemia, hyperhomocysteinemia, and smoking are well-established risk factors of cardiovascular disease [2–3]. This study was undertaken to define the influence of sex on the prevalence of conventional risk factors in 54 long-term hemodialysis patients: 24 female, 30 male (mean age in years, 60 12 female and 65 15 male; mean dialytic age in months, 59 48 female and 61 55 male). All patients received thrice-weekly dialysis and ratio of urea clearance times dialysis duration to the volume that the urea is distributed in (Kt/v) was always 1.2. No patients at the time of the study were receiving folate or vitamin B supplements. Total homocysteine (Hcy) was tested by a standard highperformance liquid chromatography (HPLC) assay and the following biochemical parameters were also tested: albumin (g/L), cholesterol (mg/dL), and triglycerides (mg/dL). Male hemodialysis patients showed significantly higher Hcy levels when compared to female hemodialysis patients (66.8 49.1 vs. 40.6 21.7, P 0.02). Mean plasma—cholesterol (200 40 males vs. 201 46 females); triglycerides (204 126 males vs. 163 64 females); and albumin (20.0 40.3 males vs. 20.1 46.2 females) did not show any statistical difference. The prevalence of hypertension defined as blood pressure 140/80 mm Hg and smoking was similar between the two groups (76% males vs. 69% females). To our knowledge, this is the first observation of a significant difference between male and female serum Hcy levels. This finding may account for the different cardiovascular risk between the 2 populations of HD patients. Therapeutic approaches aimed to treat hyperhomocysteinemia should take into account different cut-off points according to gender.

Hemodialysis stimulates hepatocyte growth factor release. Studies were performed in 26 patients on regular dialysis treatment with cuprophane (CU), polymethylmetacrilate (PMMA) or cuprammonium (CAM) dialyzers. Controls were six patients with chronic renal failure but not on regular dialysis treatment (CRF) and six healthy subjects (N). Blood was collected at the start (T0), and at 15 (T15) and 240 (T240) minutes of dialysis to measure the serum hepatocyte growth factor (HGF) concentration and to study HGF production by peripheral blood mononuclear cells (PBMC) in vitro. The form of HGF (that is, inactive/monomeric, active/dimeric) present in the serum was analyzed by immunoblotting. In addition, the ability of serum to stimulate proliferation of tubular cells (HK-2) and HGF release by PBMC and fibroblasts (MRC-5) was investigated. At T0, serum HGF levels were identical to that of the controls. In patients treated with CU, serum HGF rose from 0.24 ng/ml at T0 to 7.44 ng/ml at T15, and remained high at T240. PBMC collected at T15 and T240 released significantly more HGF in vitro than those collected at T0. Serum at T15 stimulated proliferation of HK-2 cells and the release of HGF by PBMC and MRC-5 cells. The PMMA and CAM dialyzers had similar effects as the CU. These results indicate that dialysis induces a striking rise in serum HGF and a prompt circulation of factor(s) stimulating HGF release. Dialysis-activated PBMC release HGF.

Inflammatory effects of peritoneal dialysis: Evidence of systemic monocyte activation. We evaluated in peritonitis-free patients undergoing continuous ambulatory peritoneal dialysis (CAPD) the release of both interleukin-6 (IL-6) and β-2-microglobulin (β2m) by cultured peripheral blood mononuclear cells (PBMC), as well as the levels of serum amyloid A (SAA), that is, the main hepatic acute phase protein during inflammation. The same measurements were obtained in hemodialysis (HD) patients, uremic non-dialyzed patients (ESRD) and healthy controls (CON). In CAPD, IL-6 production from PBMC was markedly increased in comparison to the control value (600.7 ± 104.3 vs. 14.2 ± 3.6 pg/3 × 106 PBMC/24 hr, P < 0.005). Similarly, a striking enhancement of the PBMC release of β2m was detected in CAPD with respect to CON (10.1 ± 2.6 vs. 0.063 ± 0.013 µg/3 × 106 PBMC/24 hr, P < 0.001). Also, the SAA levels were significantly greater in CAPD patients (21.3 ± 8.7 µg/dl) than in controls (3.14 ± 0.17 µg/dl, P < 0.05). Analogous increases of both IL-6 and β2m cell releases, as well as of SAA levels, were observed in HD patients. No difference concerning the three parameters was detected between CON and ESRD. In conclusion, CAPD induces per se PBMC activation with an enhanced release of both IL-6 and β2m; this is associated to higher levels of SAA. These systemic inflammatory effects are comparable to those observed in HD patients indicating that CAPD is similar to HD in terms of biocompatibility of the treatment.

Recombinant interleukin-2 (rIL-2) is widely used in patients with advanced cancer to enhance killer cell functions. However, the main drawback of rIL-2 therapy is the frequent development of oliguric acute renal failure (ARF), presumably due to a vascular leak syndrome. The aim of this study was to evaluate the effect of low-dose dopamine infusion on this form of ARF. Nine patients with metastatic renal cancer and previous unilateral nephrectomy were treated with a continuous intravenous infusion of rIL-2 (3 × 10 6 Cetus units/m 2 /d) for 5 days (study A). After 1 week, all the patients repeated the same cycle, but with the addition of a continuous intravenous infusion of dopamine (2 μg/min/kg body weight) that was started at the third day of treatment (study B). During study A, all patients showed a progressive (up to 34%) decrease of creatinine clearance. After rIL-2 withdrawal, these alterations persisted and were associated with a reduction in urinary output, sodium urinary excretion, and plasma protein. In study B, dopamine administration after renal function impairment (‡glomerular filtration rate=−44%) led to a prompt improvement of creatinine clearance. Creatinine clearance showed a further significant enhancement after the withdrawal of both drugs, reaching a value within the baseline range on the third day of follow-up. Similarly, the decline in urinary output and sodium excretion during rIL-2 was promptly counteracted by dopamine; in addition, after withdrawal of rIL-2 and dopamine, plasma protein levels were normalized. In conclusion, our data suggest that rIL-2-induced ARF in cancer patients is due to renal hypoperfusion mainly caused by a reduction in oncotic pressure. Importantly, intravenous infusion of dopamine at low dosage is effective in reversing this form of renal impairment; such a therapeutic approach, while reducing recovery time, avoids dose reduction or discontinuation of rIL-2 treatment.

Background. In recent years a reduction of oral cyclosporin A (CsA) dose has been adopted to minimize its adverse renal effects. To date, however, little is known about the intrinsic renal and immunological effects of low-dose CsA. Methods. Four oral doses of the drug (2, 3, 4 and 5 mg/kg body wt) and placebo (P) were randomly administered in two half-doses to seven healthy subjects. Studies were performed during water diuresis 4 h after administration of the 2nd half-dose, i.e. when the biological activity of the drug is considered maximal. Renal function was evaluated after all doses. In the same subjects, the levels of interleukin-2 (IL-2) and IL-2 receptor (IL-2R), that are the main immunological targets of CsA, were measured in the supernatant of peripheral blood mononuclear cells cultured with phytohaemagglutinin (PHA) after P, 3 and 5 mg/kg of the drug. Results. CsA induced a dose-dependent and proportional decrease of GFR and RPF associated with increasing renal vascular resistances (RVR) in presence of unmodified blood pressure. Similarly, Na + urinary excretion decreased in a dose-dependent manner due to both GFR reduction and to an higher tubular reabsorption mainly localized at the level of the proximal nephron. All these changes were significant only after 4 and 5 mg/kg. A significant suppression of PHA-stimulated IL-2 and IL-2R cell release was observed following 5 mg/kg only. Conclusions. This study suggests that nephrotoxic and immunosuppressive effects of low-dose CsA are strictly linked.

The basal production of IL-6 by cultured peripheral blood mononuclear cells (PBMC) from patients with IgAN, is markedly higher (A, 109 pg/ml) as compared to that of PBMC of either patients without clinical signs (I, 39 pg/ml) or appropriate controls (C, 44 pg/ml). When PBMC from healthy subjects were incubated in the presence of sera from patients A, the IL-6 production was strongly enhanced. No such an effect was observed by stimulating PBMC with sera from the other two groups of subjects (I, C). In another experiment we observed that the IL-6 production stimulated by serum from patients A could be inhibited by addition of specific monosaccharides. The inhibitory effect was rapidly abolished when the sugar-containing medium was substituted with the original one. Finally molecular components from serum of A were grossly separated by gel column chromatography. Individual fractions were incubated with PBMC of C: fractions with Mr > 30,000 highly stimulated the release of IL-6 (up to 1320 pg/ml); fractions with lower molecular weight were inactive. The data suggest the presence of an IL-6 releasing factor in the serum of IgAN patients. Although the chemical nature of such a factor is not yet established, the observations reported focus our attention to the lectins family. Since this factor seems potentially important in the understanding of the pathogenesis of IgAN, both its isolation and structural/functional characterization deserve further efforts.

Hemodialysis related induction of interleukin-6 production by peripheral blood mononuclear cells. Interleukin-6 (IL-6) has a complex spectrum of biological activities, for example, growth and differentiation of B cells and synthesis of acute-phase proteins by the liver. To evaluate the role of this cytokine in the inflammatory response induced by blood interaction with hemodialysis membranes, we have investigated the IL-6 synthesis and release in supernatant of 24-hour cultured peripheral blood mononuclear cells (PBMC) isolated from: (a) 10 hemodialyzed patients, (b) seven patients with advanced chronic renal failure (GFR ≤10 ml/min), and (c) eight healthy control subjects. In the same groups of subjects we evaluated the relationship between IL-6 synthesis and release and beta-2-microglobulin (β2m) production. Before and after dialytic treatment hemodialysis patient blood samples were drawn using the following criteria: (1) after two months of dialysis with cuprophan membranes, (2) after one and two months of dialysis with polymethylmethacrylate (PMMA) membranes, and finally, (3) after one further month of dialysis with cuprophan membranes. IL-6 was determined after 72 hours of incubation of PBMC supernatant serial dilutions with IL-6-dependent hybridoma cell line, 7TD1. Compared to IL-6 synthesis in control subjects (6.0 ± 5.6 U/3 × 106 PBMC/24 hr), hemodialyzed patients, when treated with cuprophan membranes, showed significantly higher value of IL-6 production both before (23 ± 13 U/3 × 106 PBMC/24 hr) and after (26.2 ± 11.3 U/3 × 106 PBMC/24 hr) the dialytic session. When patients were hemodialyzed with PMMA membranes, at the start of dialysis IL-6 levels were not significantly different from values observed in healthy controls (10.6 ± 4 U/3 × 106 PBMC/24 hr, after 1 month of dialysis and 7.8 U/3 × 106 PBMC/24 hr, after 2 months, respectively). When the patients were switched back to cuprophan membranes, IL-6 production was greatly increased after one month of dialysis (CU2, 44.6 ± 9.4 U/3 × 106 PBMC/24 hr, at the start of dialysis) reaching values significantly higher than those obtained in the first period with cuprophan membranes. No difference was observed between the values of IL-6 production obtained pre- and post-dialysis with cuprophan or PMMA membranes. IL-6 production values in uremic non-dialyzed patients were similar to values found in control subjects (8.6 ± 6.4 U/3 × 106 PBMC/24 hr). β2m release showed a behavior quite similar to IL-6 throughout the study. In fact, a statistically significant linear relationship was obtained between β2m and IL-6 values of production (r = 0.8296, P < 0.001). In conclusion, our results show higher levels of IL-6 production in hemodialyzed patients treated with cuprophan membranes, thereby suggesting a chronic stimulation. β2m production is highly related to IL-6 production; this relationship suggests a possible implication for this cytokine in the pathogenesis of dialysis amyloidosis.

Renal functional reserve: Its significance in normal and salt depletion conditions. The aim of this study was the evaluation, in healthy subjects, of the renal functional reserve (RFR), that is, the GFR increase induced by a combined infusion of amino acids (AA) and dopamine (D), in conditions of extracellular volume depletion caused by diuretic administration. In particular, this study was undertaken: a) to evaluate whether and to which extent, AA + D can reverse the functional GFR impairment induced by salt depletion, without volume restoration; b) to study whether any relationship may be found between the GFR in normal condition (the so-called “resting” GFR), and/or the renal functional reserve and the GFR impairment induced by salt depletion, in order to understand the role of both “resting” GFR and RFR in the degree of renal dysfunction induced by salt depletion. In control conditions the i.v. infusion of AA + D significantly increased RPF (+ 41% vs. baseline period) with a mean absolute increase of 211 ml/min. A similar pattern was observed in GFR behavior (+ 31.5% with 34 ml/min of mean absolute increase). A significant inverse exponential relationship was observed between GFR before A A + D i.v. infusion (“resting” GFR) and renal functional reserve (P < 0.05), suggesting that, in normal conditions, these inversely related parameters may widely vary according to the tone of the glomerular arterioles. Following salt depletion, we observed a variable degree of GFR impairment. Both GFR and RPF were significantly decreased (-25.9%, P < 0.05 and -29%, P < 0.05, respectively). The GFR impairment was mainly caused by a significant increase in tone of glomerular arterioles presumably induced by vasoactive substances (angiotensin, catecholamines) as mirrored by the increase of both plasma renin activity (PRA) and urinary norepinephrine (NE) excretion (+164% and +426%, respectively, vs. control period). AA + D infusion after salt depletion determined a striking rise of both GFR (+30 ml/min, corresponding to 37%) and RPF (+193 ml/min, corresponding to 31%) versus the baseline study of salt depleted condition. The GFR value obtained by AA + D i.v. infusion in the normal condition, however, was not reached presumably because of persistence of extracellular volume contraction, which was confirmed by the persistence of high values of PRA and NE urinary excretion and low values of urinary sodium excretion after AA + D i.v. infusion. GFR impairment due to salt depletion was directly related to the “resting” GFR (P < 0.05) and inversely related to the RFR (P < 0.01): the latter relationship suggests that the greater the “resting” tone of glomerular arterioles (and consequently the value of the RFR), the more minor the role of renal vasoconstriction in causing the fall of GFR following salt depletion. Finally, AA + D infusion in the salt depleted condition induced a GFR increase that is inversely related to the GFR value obtained after salt depletion (P < 0.05). This finding suggests that glomerular arteriolar tone influences, also in a salt depletion condition, the response to AA + D infusion: subjects with a lower GFR (with a greater vasoconstriction), in fact, show a greater increase in GFR after the infusion of these vasodilating substances. depletion condition, the response to AA + D infusion: subjects with a lower GFR (with a greater vasoconstriction), in fact, show a greater increase in GFR after the infusion of these vasodilating substances.

Mycophenolate mofetil is an immunosuppressive agent that blocks purine biosynthesis, inhibits T and B-lymphocyte and mesangial proliferation. Mycophenolate mofetil is not nephrotoxic like calcineurin inhibitors and is widely used in solid-organ transplantation. Recently, mycophenolate mofetil has been introduced in the treatment of autoimmune diseases and primary glomerulopathies. This review analyzes the literature currently available on the treatment of primary glomerulopathies with mycophenolate mofetil. Encouraging results have been obtained in minimal change nephropathy where it may help to reduce the use of steroids in these patients who are often very young. The results obtained in medium and high risk patients with focal segmental glomerulonephritis and idiopathic membranous nephropathy were less encouraging. Conflicting results have been reported on IgA nephropathy in controlled trials. None of these studies attained level A evidence, meaning that randomized control trials of sufficient statistical significance are necessary to estimate the real effectiveness of mycophenolate mofetil in primary glomerulopathies.

Previously, the authors reported that the serum of patients with immunoglobulin (Ig) A nephropathy stimulated peripheral leukocytes, and this effect was inhibited by nominal haptens for lectins. In vitro studies have shown that lectins can bind to rat mesangial cells and cause their activation. This study was performed to investigate whether the serum of IgA nephropathy patients contains lectins that activate mesangial cells, i.e., induce release of interleukin (IL)-6, a nephritogenic cytokine. The serum of patients was adsorbed by affinity chromatography on resins loaded with lectin-binding sugars. After adsorption, serum supernatant was collected and the resins were then eluted. Human mesangial cells were conditioned with native serum, post-adsorption supernatant, and eluate (all three at 10%) for 24 h, and the release of IL-6 was determined by ELISA. Normal serum was used as control. Incubation of mesangial cells with IgA nephropathy patients serum raised average IL-6 release from 8.5 pg/mL to 274.1 pg/mL. Adsorption in beta-D-glucose and N-acetyl-D-glucosamine caused a fall in the activity of patients' serum, to 17.0 and 63.7 pg/mL, respectively, and the activity lost was recovered in the eluate (185.2 and 142.7 pg/mL, respectively). Neither adsorption on N-acetyl-D-galactosamine nor on fucosylamine was associated with any effect on serum activity; accordingly, no activity was found in the eluates. Serum of patients with non-IgA mesangiocapillary nephritis did not stimulate mesangial cells. These results show that the serum of IgA nephropathy patients contains specific lectins that stimulate IL-6 nephropathy by mesangial cells and are, therefore, potential nephritogenic.

To the Editor: Homocysteine has an inhibitory effect on angiogenesis1. However, the vascular endothelial growth factor receptor-2 (VEGFR-2) gene has recently been found up-regulated on human atherosclerotic plaques2. In order to analyze the association between homocysteine and VEGFR-2 serum levels, we have randomly selected 26 regular hemodialysis (HD) patients ages 56 12 years (mean SD; M = 14, F = 12), and 26 age-matched kidney transplanted individuals (KTx), ages 52 8 years (M = 21, F = 5). KTx transplant age was 13 9 months and creatinine was 1.6 0.5 mg/dL. Nine age-matched healthy volunteers (47 5 years) were also recruited. HD samples were collected at the end of the long interval period. Serum homocysteine (Hcy) and VEGFR-2 were tested by high-performance liquid chromatography (HPLC) with fluorimetric detection and a commercial enzyme-linked immunosorbent assay (ELISA) kit, respectively. Hcy was higher in HD patients (57 36 mol/L) than in KTx patients (23 8 mol/L; P < 0.001) and control patients (15 6 mol/L; P < 0.01 vs. HD; P < 0.05 vs. KTx). VEGFR-2 was lower in HD patients (1705 387 pg/mL) than in KTx patients (2449 825 pg/mL; P = 0.014) or control patients (2150 464 pg/mL) Figure 1. The present study shows that Hcy and circulating VEGFR-2 are inversely associated, consistent with previous reports showing that homocysteine inhibits angiogenesis. Our data also suggest that up-regulation of the VEGFR-2 gene is probably a local finding, and that hyperhomocysteinemia may be involved in the release of VEGFR-2 into the systemic circulation.