Haematological malignancies and acute kidney injury requiring nephrology consultation: challenging the worst of the worst.

BACKGROUND: Acute kidney injury (AKI) often complicates the course of haematological malignancies (HMs) and confers a worse prognosis. The majority of these patients are managed by the attending physician, yet, a small group, mostly coincident with the worst presentation and outcomes, requires nephrology consultation, challenging the clinician with ethical issues regarding the decision to initiate or forgo renal support therapy. The purpose of this work is to identify the prognostic determinants for in-hospital mortality in this population. METHODS: A retrospective, observational chart review was undertaken at a single tertiary referral oncological centre. We reviewed the medical records of in-hospital patients with AKI and HM between 1 January 1995 and 31 December 2014 who met the criteria for RIFLE (Risk, Injury, and Failure; and Loss; and End-stage kidney disease) classification of I or higher and were followed by a nephrologist. RESULTS: Three hundred and forty-five patients were included in the study. Predictors of in-hospital death in patients with HM and AKI were septic shock [odds ratio (OR) 4.290 (95% CI 2.058-8.943)], invasive mechanical ventilation (IMV) [OR 4.305 (95% CI 2.075-8.928)] and allogeneic stem cell transplantation (SCT) [OR 2.232 (95% CI 1.260-3.953)]. The combination of each risk factor was used to estimate the probability of dying. Patients with all three risk factors had a risk of death of 86%. CONCLUSIONS: Septic shock, IMV and allogeneic SCT were identified as independent predictors of death in patients with HM and AKI, with only a small chance of survival if all three were present. Depending on the combination of risk factors, the indication for aggressive life support therapies, such as RST, might be questionable.

Effect of membrane permeability on survival of hemodialysis patients.

The effect of high-flux hemodialysis membranes on patient survival has not been unequivocally determined. In this prospective, randomized clinical trial, we enrolled 738 incident hemodialysis patients, stratified them by serum albumin < or = 4 and >4 g/dl, and assigned them to either low-flux or high-flux membranes. We followed patients for 3 to 7.5 yr. Kaplan-Meier survival analysis showed no significant difference between high-flux and low-flux membranes, and a Cox proportional hazards model concurred. Patients with serum albumin < or = 4 g/dl had significantly higher survival rates in the high-flux group compared with the low-flux group (P = 0.032). In addition, a secondary analysis revealed that high-flux membranes may significantly improve survival of patients with diabetes. Among those with serum albumin < or = 4 g/dl, slightly different effects among patients with and without diabetes suggested a potential interaction between diabetes status and low serum albumin in the reduction of risk conferred by high-flux membranes. In summary, we did not detect a significant survival benefit with either high-flux or low-flux membranes in the population overall, but the use of high-flux membranes conferred a significant survival benefit among patients with serum albumin < or = 4 g/dl. The apparent survival benefit among patients who have diabetes and are treated with high-flux membranes requires confirmation given the post hoc nature of our analysis.

Changes in red blood cells membrane protein composition during hemodialysis procedure.

Our aim was to evaluate the influence of the hemodialysis (HD) procedure in red blood cells (RBC) membrane protein composition. We evaluated hematological data (RBC count, hemoglobin concentration, and hematimetric indices) and RBC membrane protein composition (linear and exponential gradient polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate [SDS-PAGE] followed by densitometry analysis of RBC membrane proteins) before and immediately after the HD procedure in 20 patients (10 responders and 10 non-responders to recombinant human erythropoietin therapy [rhEPO]) and 26 healthy controls. Before HD, patients presented anaemia and significant changes in membrane protein composition, namely, a statistically significant reduction in spectrin associated with a significant increase in bands 6, as well as an altered membrane protein interaction (protein 4.1/spectrin, protein 4.1/band 3, protein 4.2/band 3 and spectrin/band 3). After HD, we found that patients showed a statistically significant increase in RBC count and hemoglobin, a further and statistically significant decrease in spectrin, an increase in band 3, and an altered spectrin/band 3 ratio. When comparing responders and non-responders patients after HD, we found that the non-responders presented a trend to a higher reduction in spectrin. Our data suggest that HD procedure seems to contribute to a reduction in spectrin, which is normally associated with a reduction in RBC deformability, being that reduction in spectrin is higher in non-responder patients.

Neutrophil activation and resistance to recombinant human erythropoietin therapy in hemodialysis patients.

AIM: The aim of this work was to evaluate the neutrophil activation state in chronic kidney disease (CKD) patients under hemodialysis, and its linkage with resistance to recombinant human erythropoietin (rhEPO) therapy. METHODS: We studied 63 CKD patients under hemodialysis and rhEPO treatment (32 responders and 31 non-responders to rhEPO therapy). In 20 of the CKD patients (10 responders and 10 non-responders to rhEPO therapy), blood samples were also collected immediately after dialysis. Twenty-six healthy volunteers were included in a control group. Hemoglobin levels, total and differential leukocyte counts, and circulating levels of C-reactive protein (CRP), elastase and lactoferrin were measured in all patients and controls. RESULTS: Compared with controls, CKD patients presented with significantly higher CRP, neutrophil and elastase levels. When we compared the 2 groups of patients, we found that non-responders presented statistically significantly higher elastase plasma levels. A positive significant correlation was found between elastase levels and weekly rhEPO dose and CRP serum levels. After the hemodialysis procedure, a statistically significant rise in elastase, lactoferrin and, elastase/neutrophil and lactoferrin/neutrophil ratios were found. CONCLUSIONS: Our data show that CKD patients under hemodialysis present higher elastase levels (particularly in non-responding patients), which could be related to the rise in neutrophils, and to be part of the enhanced inflammatory process found in these patients.

Altered erythrocyte membrane protein composition in chronic kidney disease stage 5 patients under haemodialysis and recombinant human erythropoietin therapy.

Our aim was to evaluate red blood cell (RBC) membrane protein composition in chronic kidney disease (CKD) stage 5 patients under haemodialysis (HD) and recombinant human erythropoietin (rhEPO) therapy, and its linkage to rhEPO hyporesponsiveness. We evaluated in 63 CKD stage 5 patients (32 responders and 31 non-responders to rhEPO therapy) and in 26 healthy controls RBC count, haematocrit, haemoglobin concentration, haematimetric indices, reticulocyte count, reticulocyte production index, RBC osmotic fragility test and membrane protein analyses. CKD stage 5 patients presented significant changes in membrane protein composition, namely a reduction in spectrin, associated to altered protein 4.1/spectrin and spectrin/band 3 ratios. Non-responder CKD stage 5 patients were more anaemic, with more microcytic and anisocytic RBCs, than responders; significantly altered ankyrin/band 3 and spectrin/ankyrin ratios were also observed. CKD stage 5 patients under HD are associated with an altered protein membrane structure, which seems to the disease itself and/or to the interaction with HD membranes.

Role of prohepcidin, inflammatory markers and iron status in resistance to rhEPO therapy in hemodialysis patients.

The aim of our study was to assess possible relations between prohepcidin, iron status and inflammatory markers in hemodialysis (HD) patients, as well as its association with resistance to recombinant human erythropoietin (rhEPO) therapy. Fifty HD patients and 25 healthy controls were enrolled in the study. Among HD patients, 25 were non-responders and 25 were responders to rhEPO therapy. Complete blood cell count, reticulocyte count, and circulating levels of ferritin, iron, transferrin saturation, C-reactive protein (CRP), soluble interleukin (IL)-2 receptor (s-IL2R), soluble transferrin receptor (s-TfR), IL-6 and prohepcidin were measured in all patients and controls. HD patients showed higher circulating levels of ferritin, s-TfR, CRP, IL-6, s-IL2R and prohepcidin, and lower levels of transferrin compared to healthy controls. Higher levels of s-TfR, CRP and lower levels prohepcidin were observed among non-responders compared to responders. Prohepcidin levels correlated negatively with s-TfR and reticulocyte count. The weekly rhEPO/kg dose was found to be positively correlated with CRP, hemoglobin and s-TfR. In conclusion, our data show that a close interaction exists between inflammation, iron status and prohepcidin serum levels that ultimately regulate intracellular iron availability. Prohepcidin and s-TfR, together with CRP, may prove to be good markers of resistance to rhEPO therapy in HD patients.

Inflammation, T-cell phenotype, and inflammatory cytokines in chronic kidney disease patients under hemodialysis and its relationship to resistance to recombinant human erythropoietin therapy.

BACKGROUND: Resistance to recombinant human erythropoietin (rhEPO) occurs in some chronic kidney disease (CKD) patients, which may be due to enhanced systemic inflammatory response and to the erythropoiesis-suppressing effect of pro-inflammatory cytokines, some of which are produced by T cells. AIM OF STUDY: The aim of this study was to investigate the relationship between resistance to rhEPO therapy in hemodialysis CKD patients and inflammatory markers [C-reactive protein (CRP), soluble interleukin (IL)-2 receptor (sIL2R), and serum albumin levels], blood cell counts, T-cell phenotype, cytokine production by T cells, and serum cytokine levels. MATERIALS AND METHODS: We studied 50 hemodialysis CKD patients, 25 responders and 25 nonresponders to rhEPO, and compared them to each other and with 25 healthy controls. When compared to controls, CKD patients showed increased serum levels of CRP, IL-6, and sIL2R and a T-cell lymphopenia, due to decreased numbers of both CD4+ and CD8+ T cells. T cells from CKD patients had an immunophenotype compatible with chronic T-cell stimulation as shown by the increased percentage of CD28-, CD57+, HLA-DR+, CD28-HLA-DR+, and CD57+ HLA-DR+ T cells and produce higher levels of IL-2, INF-gamma, and TNF-alpha after short-term in vitro stimulation, although Th1 cytokines were not detectable in serum. Statistically significant differences were found between responders and nonresponders to rhEPO therapy for total lymphocyte and CD4+ T-lymphocyte counts, albumin (lower in nonresponders) and CRP (higher in nonresponders) levels. CONCLUSION: CKD patients under hemodialysis present with raised inflammatory markers and decrease of total lymphocyte and CD4+ T-lymphocyte counts when compared with controls. Some of those markers are even further enhanced in nonresponders to rhEPO therapy patients, but resistance to this therapy cannot be justified by a Th1 polarized T-cell response.

The MPO Study: just a European HEMO Study or something very different?

Although results from observational and epidemiological studies suggested a survival benefit associated with high-flux hemodialysis, conclusive evidence from prospective randomized clinical trials has been lacking. Both the HEMO Study in the USA and the Membrane Permeability Outcome Study (MPO Study) in Europe are randomized studies investigating the effect of high- and low-flux hemodialysis on patient outcomes, even though there were some significant differences in the design of the two studies. An earlier randomized clinical trial could not show differences on patient survival between patient groups being treated with membranes of different material and permeability, but this trial was not designed specifically to examine this particular endpoint. Based on these previous experiences, the MPO Study addressed a hemodialysis patient population which was considered to be more susceptible to the intervention with high-flux dialysis. To identify these patients with an elevated risk, low serum albumin levels were chosen as an indicator; low serum albumin is associated with malnutrition, inflammation, atherosclerosis, and with increased risk of morbidity and mortality. Together with low serum albumin, patients had to be new to dialysis to be selected for the MPO Study. These particular considerations on patient selection, together with additional methodological refinements in the study design allow the conclusion that the MPO Study is valid on its own rather than being a European version of the HEMO Study.

Minimal change nephrotic syndrome after stem cell transplantation: a case report and literature review.

Graft-versus-host disease is one of the most frequent complications occurring after haematopoietic stem cell transplantation. Recently, renal involvement has been described as a manifestation of chronic graft-versus-host disease. Immunosuppression seems to play a major role: clinical disease is triggered by its tapering and resolution is achieved with the resumption of the immunosuppressive therapy. Prognosis is apparently favourable, but long term follow up data are lacking.We report a case of a 53-year-old man who developed nephrotic syndrome 142 days after allogeneic stem cell transplantation for acute myeloid leukaemia. Onset of nephrotic syndrome occurred after reduction of immunosuppressants and was accompanied by manifestations of chronic graft-versus-host disease. Histological examination of the kidney was consistent with Minimal Change Disease. After treatment with prednisolone and mycophenolate mofetil he had complete remission of proteinuria and improvement of graft-versus-host disease. Eighteen months after transplantation the patient keeps haematological remission and normal renal function, without proteinuria.Since patients with chronic graft-versus-host disease might be considered at risk for development of nephrotic syndrome, careful monitoring of renal parameters, namely proteinuria, is advisable.

Oral health status in patients with moderate-severe and terminal renal failure.

AIMS: To evaluate the oral health status of patients with moderate-severe chronic renal failure (CRF) and with terminal renal failure (TRF). DESIGN: The study group was formed of 50 patients: 22 (44%) with moderate-severe CRF and 28 (56%) with TRF included in a haemodialysis programme. The controls (n=64) presented similar characteristics with regard to sex, age, weight and educational level. A single dentist performed an intraoral examination on all the subjects, gathering information on: number of decayed, missing or filled teeth; supragingival plaque accumulation; calculus deposits; periodontal pockets in the Ramfjord teeth; and depth of loss of insertion. RESULTS: No significant differences were detected in the values of the DMF index between the two groups. The mean number of decayed teeth was lower in the patients than in the controls, showing a tendency to statistical significance (p=0.052). The mean number of missing teeth was higher in the patients than in the controls (p=0.002). Twelve patients and seven controls were completely edentate. The mean number of filled teeth was significantly lower in the patients than the controls (p<0.001). Supragingival plaque accumulation and the loss of insertion were significantly greater in the patients than in the controls (p=0.006 and p<0.001, respectively). No significant differences were found with respect to the calculus deposits or to the presence of periodontal pockets in the two groups. The value of the DMF index, the mean number of teeth with caries and the number of filled teeth were significantly higher in the patients with moderate-severe CRF than in the patients with TRF (p=0.004, p=0.030 and p=0.006, respectively). CONCLUSIONS: Patients with CRF have a lower prevalence of caries, more supragingival plaque, more teeth with a loss of insertion and more missing teeth than the healthy controls. The prevalence of caries is affected by the severity of the renal failure and/or by haemodialysis treatment.

The effects of control of thermal balance on vascular stability in hemodialysis patients: results of the European randomized clinical trial.

BACKGROUND: Many reports note that the use of cool dialysate has a protective effect on blood pressure during hemodialysis (HD) treatments. However, formal clinical trials in which dialysate temperature is tailored to the body temperature of appropriately selected hypotension-prone patients are lacking. METHODS: We investigated the effect of thermal control of dialysate on hemodynamic stability in hypotension-prone patients selected from 27 centers in nine European countries. Patients were eligible for the study if they had symptomatic hypotensive episodes in 25% or more of their HD sessions, assessed during a prospective screening phase over 1 month. The study is designed as a randomized crossover trial with two phases and two treatment arms, each phase lasting 4 weeks. We used a device allowing the regulation of thermal balance (Blood Temperature Monitor; Fresenius Medical Care, Bad Homberg, Germany), by which we compared a procedure aimed at preventing any transfer of thermal energy between dialysate and extracorporeal blood (thermoneutral dialysis) with a procedure aimed at keeping body temperature unchanged (isothermic dialysis). RESULTS: One hundred sixteen HD patients were enrolled, and 95 patients completed the study. During thermoneutral dialysis (energy flow rate: DeltaE = -0.22 +/- 0.29 kJ/kg x h), 6 of 12 treatments (median) were complicated by hypotension, whereas during isothermic dialysis (energy flow rate: DeltaE = -0.90 +/- 0.35 kJ/kg x h), the median decreased to 3 of 12 treatments (P < 0.001). Systolic and diastolic blood pressures and heart rate were more stable during the latter procedure. Isothermic dialysis was well tolerated by patients. CONCLUSION: Results show that active control of body temperature can significantly improve intradialytic tolerance in hypotension-prone patients.