Distribution, preparedness and management of Ukrainian adult refugees on dialysis-an international survey by the Renal Disaster Relief Task Force of the European Renal Association.

BACKGROUND: Due to the Russian-Ukrainian war, some of the about 10 000 adults requiring dialysis in Ukraine fled their country to continue dialysis abroad. To better understand the needs of conflict-affected dialysis patients, the Renal Disaster Relief Task Force of the European Renal Association conducted a survey on distribution, preparedness and management of adults requiring dialysis who were displaced due to the war. METHODS: A cross-sectional online survey was sent via National Nephrology Societies across Europe and disseminated to their dialysis centers. Fresenius Medical Care shared a set of aggregated data. RESULTS: Data were received on 602 patients dialyzed in 24 countries. Most patients were dialyzed in Poland (45.0%), followed by Slovakia (18.1%), Czech Republic (7.8%) and Romania (6.3%). The interval between last dialysis and the first in the reporting center was 3.1 ± 1.6 days, but was ≥4 days in 28.1% of patients. Mean age was 48.1 ± 13.4 years, 43.5% were females. Medical records were carried by 63.9% of patients, 63.3% carried a list of medications, 60.4% carried the medications themselves and 44.0% carried their dialysis prescription, with 26.1% carrying all of these items and 16.1% carrying none. Upon presentation outside Ukraine, 33.9% of patients needed hospitalization. Dialysis therapy was not continued in the reporting center by 28.2% of patients until the end of the observation period. CONCLUSIONS: We received information about approximately 6% of Ukrainian dialysis patients, who had fled their country by the end of August 2022. A substantial proportion were temporarily underdialyzed, carried incomplete medical information and needed hospitalization. The results of our survey may help to inform policies and targeted interventions to respond to the special needs of this vulnerable population during wars and other disasters in the future.

Lessons learned during the war in Ukraine: a report from the Renal Disaster Relief Task Force of the ERA.

People living with kidney disease are among the most vulnerable at times of natural or man-made disasters. In addition to their unpredictable course, armed conflicts impose a major threat given the disruption of infrastructure, sanitation and access to food, water and medical care. The ongoing war in Ukraine has once more demonstrated the importance of preparedness, organization, coordination and solidarity during disasters. People living with kidney disease face serious challenges given their dependence on life-sustaining treatment, irrespective of whether they remain in the war zone or are displaced internally or externally. This especially affects those requiring kidney replacement therapy, dialysis or transplantation, but also patients with other kidney diseases and the medical staff who care for them. Soon after the war started, the European Renal Association assigned a Renal Disaster Relief Task Force dedicated to support the people living with kidney disease and the nephrology community in Ukraine. This report summarizes the major challenges faced, actions taken and lessons learned by this task force. We anticipate that the experience will help to increase preparedness and mitigate the devastating effects of armed conflicts on the kidney community in the future and propose to establish an international collaboration to extend this effort to other parts of the world facing similar challenges.

Armed conflicts and kidney patients: a consensus statement from the Renal Disaster Relief Task Force of the ERA.

During conflicts, people with kidney disease, either those remaining in the affected zones or those who are displaced, may be exposed to additional threats because of medical and logistical challenges. Acute kidney injury developing on the battlefield, in field hospitals or in higher-level hospital settings is characterized by poor outcomes. People with chronic kidney disease may experience treatment interruptions, contributing to worsening kidney function. Patients living on dialysis or with a functioning graft may experience limitations of dialysis possibilities or availability of immunosuppressive medications, increasing the risk of severe complications including death. When patients must flee, these threats are compounded by unhealthy and insecure conditions both during displacement and/or at their destination. Measures to attenuate these risks may only be partially effective. Local preparedness for overall and medical/kidney-related disaster response is essential. Due to limitations in supply, adjustments in dialysis frequency or dose, switching between hemodialysis and peritoneal dialysis and changes in immunosuppressive regimens may be required. Telemedicine (if possible) may be useful to support inexperienced local physicians in managing medical and logistical challenges. Limited treatment possibilities during warfare may necessitate referral of patients to distant higher-level hospitals, once urgent care has been initiated. Preparation for disasters should occur ahead of time. Inclusion of disaster nephrology in medical and nursing curricula and training of patients, families and others on self-care and medical practice in austere settings may enhance awareness and preparedness, support best practices adapted to the demanding circumstances and prepare non-professionals to lend support.

Chronic Kidney Disease in Balkan Countries-A Call to Action for Timely Diagnosis and Monitoring.

Chronic kidney disease (CKD) is a serious illness with important consequences for patients and health systems. Estimation of prevalence and incidence, especially in early stages, is difficult due to a lack of epidemiological studies and consolidated registries. In general, the disease awareness is low, and thus CKD is not timely diagnosed in most cases. Robust screening programs are not implemented in Eastern European countries. A panel consisting of Primary Care Physicians and Nephrologists from Bulgaria, Croatia, Serbia, and Slovenia virtually met in December 2021 to discuss current CKD awareness and diagnostic approaches in the Balkan area The meeting resulted in specific calls to action in the region to improve the number and quality of epidemiology studies and the level of awareness among patients and medical communities, as well as implementation of screening programs in high-risk populations. Collaboration between specialists was acknowledged as a crucial driver for optimal management of patients with CKD. Joint efforts are required to persuade healthcare authorities to establish specific policies for better care of kidney patients.

Complement activation and cryoglobulinemia are common in monoclonal gammopathy of renal significance: Data from a case series.

INTRODUCTION: Monoclonal gammopathy of renal significance (MGRS) denotes kidney diseases caused by monoclonal immunoglobulins in patients who do not have an overt hematological malignancy. Treatment is primarily directed against the underlying clone. Complement activation and cryoglobulinemia are known factors that can contribute to tissue damage, however, the full extent of their involvement is not clear. MATERIALS AND METHODS: This was a retrospective study including all patients with MGRS referred for consultation to our hospital over a 3-year period. RESULTS: We identified 17 patients, of which 12 had proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID). Treatment with anti-clonal or immunosuppressive therapy was successful in 60% of patients with PGNMID, and treatment success was more common in patients with λ chain (100%) compared to κ chain deposits (20%). Serum markers of complement involvement were identified in 41% of all patients (88% of tested samples), most commonly high serum C5b-9 values or anti-factor H autoantibodies (both 24%). Patients with complement involvement did not respond well to treatment, which was unsuccessful in all treated patients with anti-factor H autoantibodies and 75% of patients with high serum C5b-9 values. Cryoglobulinemia was identified in 29% of all patients (71% tested samples) and was monoclonal in 40% of positive cases and mixed in 60%. None of the patients with cryoglobulinemia had organized deposits, however, there was a trend toward more common intramembranous deposits. In patients with monoclonal cryoglobulinemia both anti-clonal and immunosuppressive treatment were unsuccessful. All patients with mixed cryoglobulinemia were treated successfully with immunosuppressive therapy. CONCLUSION: Treatment of patients with PGNMID was successful in most cases. Complement involvement as well as monoclonal and mixed cryoglobulinemia were relatively common in our cohort, with the first two generally associated with unsuccessful treatment and the latter with successful treatment.

The predictive value of urinary erythrocyte morphology for proliferative glomerular kidney disease.

BACKGROUND AND AIM: Glomerular erythrocyturia (GlomEry) is usually associated with proliferative kidney diseases. In our retrospective cohort, we aimed to validate the predictive value of GlomEry criteria ≥ 40% dysmorphic erythrocytes (DysEry) or ≥ 5% acanthocytes (AcaEry) or at least 1 erythrocytic cast (CastEry) and of two new indices - the count of DysEry per high power field (HPF) and per microliter of urine (Stansfeld-Webb (SW)) method, for proliferative disease. MATERIALS AND METHODS: We included patients with erythrocyturia from 2015 to 2016. Based on renal histology, we divided them into a proliferative and a non-proliferative disease group. Urine erythrocyte count was done using SW and urinary sediment examination was carried out by skilled nephrologists. Sensitivity, specificity, and cutoff values were determined using ROC curves. RESULTS: We included 90 patients (33% women), median age of 63 (IQR 51, 71) years. In the proliferative group, proteinuria was lower (2.4 vs. 6.6 g/day), and SW erythrocyturia was higher (174 (IQR 60, 353) vs. 44 (IQR 20, 67) × 106/L) than in the non-proliferative group. The threshold to differentiate between the proliferative and non-proliferative group was determined at ˃ 43% of DysEry (sensitivity 73%, specificity 79%, AUC 0.808) and at ˃ 2% AcaEry (sensitivity 71%, specificity 56%, AUC 0.647). No significant difference in CastEry was found between groups. Among tested parameters, the calculated number of DysEry/HPF > 6.7 (sensitivity 77%, specificity 92%, AUC 0.878), followed by DysEry/SW > 28 × 106/L (sensitivity 76%, specificity 86%, AUC 0.879), discriminated those two groups best. CONCLUSION: In concordance with known GlomEry criteria, > 43% of DysEry predicted proliferative kidney disease, whereas CastEry did not, and AcaEry predicted poorly. The best predictor of proliferative glomerular disease was DysEry/HPF, closely followed by DysEry/SW.

Secondary oxalate nephropathy in a patient with exocrine pancreatic insufficiency successfully treated, with complete kidney recovery.

INTRODUCTION: Oxalate nephropathy is a relatively rare and under-recognized condition that commonly presents as acute kidney injury (AKI) and often leads to end-stage renal disease. Complete recovery of kidney function is extremely rare even when treatment is instituted early on. CASE PRESENTATION: We present the case of a 68-year-old man with known type 2 diabetes mellitus and an asymptomatic unrecognized exocrine pancreatic insufficiency, who was admitted due to dialysis-dependent AKI. Kidney biopsy revealed oxalate nephropathy. A wide diagnostic assessment and a multi-factorial treatment plan that included a change of diet, therapy for exocrine pancreatic insufficiency and fat malabsorption, sodium bicarbonate and potassium citrate, calcium supplements with meals, and methylprednisolone, resulted in complete recovery of kidney function. CONCLUSION: It is important for physicians to be aware of oxalate nephropathy in cases of prolonged AKI. After confirmation of diagnosis, a wide diagnostic approach is imperative to identify all the causes that have led to oxalosis. A multi-factorial therapeutic approach can lead to complete kidney recovery.

Glomerular and tubulointerstitial foscarnet nephropathy of kidney allograft with emphasis on ultrastructural findings: A case report.

INTRODUCTION: Foscarnet (trisodium phosphonoformate hexahydrate) is standard treatment for ganciclovir-resistant cytomegalovirus (CMV) infections. In the kidney, foscarnet-induced injury may be attributed to reversible tubulointerstitial lesions, but foscarnet crystals have also been observed within glomerular capillaries, suggesting that foscarnet can lead to glomerular lesions such as crescentic glomerulonephritis. We present biopsy and autopsy findings of foscarnet induced nephropathy in a transplanted kidney, with a particular emphasis on the histopathology and electron micrographic peculiarities of drug crystal deposits. CASE PRESENTATION: A 72-year-old Caucasian male patient with a deceased donor kidney was treated with several foscarnet applications due to ganciclovir-resistant CMV infection. Transplant kidney biopsy revealed massive glomerular crystalline precipitates, resulting in crescentic glomerulonephritis and tubular damage. The last foscarnet application was complicated with several infections and kidney graft failure. Autopsy revealed multi-organ damage due to foscarnet crystal precipitations associated with systemic CMV and fungal infection. On autopsy of kidney specimens, we succeeded in preserving the rectangular flat plate-like foscarnet crystals in stacks detected by transmission electron microscopy (TEM) after 100% alcohol fixation. The chemical composition of the crystals was confirmed by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. CONCLUSION: Transplant kidney biopsy remains the gold standard in distinguishing between foscarnet crystalline glomerular and/or tubulointerstitial lesions, and various forms of rejection and other causes of impaired renal function in transplant kidney.

Intrahost Norovirus Evolution in Chronic Infection Over 5 Years of Shedding in a Kidney Transplant Recipient.

Noroviruses are the leading cause of acute gastroenteritis, and they can affect humans of all age groups. In immunocompromised patients, norovirus infections can develop into chronic diarrhea or show prolonged asymptomatic virus shedding. Chronic norovirus infections are frequently reported for solid organ transplant recipients, with rapid intrahost norovirus evolution seen. In this report, we describe a case of chronic norovirus infection in an immunocompromised patient who was followed up for over 5 years. The purpose of the study was to specify the norovirus evolution in a chronically infected immunocompromised host and identify possible selection sites in norovirus capsid protein. During the follow-up period, 25 sequential stool samples were collected and nine of them were selected to generate amplicons covering viral RNA-dependent RNA polymerase (RdRp) and viral capsid protein (VP1) genes. Amplicons were sequenced using next-generation sequencing. Single nucleotide polymorphisms were defined, which demonstrated a nearly 3-fold greater mutation rate in the VP1 genome region compared to the RdRp genome region (7.9 vs. 2.8 variable sites/100 nucleotides, respectively). This indicates that mutations in the virus genome were not accumulated randomly, but are rather the result of mutant selection during the infection cycle. Using ShoRAH software we were able to reconstruct haplotypes occurring in each of the nine selected samples. The deduced amino-acid haplotype sequences were aligned and the positions were analyzed for selective pressure using the Datamonkey program. Only 12 out of 25 positive selection sites were within the commonly described epitopes A, B, C, and D of the VP1 protein. New positive selection sites were determined that have not been described before and might reflect adaptation of the norovirus toward optimal histo-blood-group antigen binding, or modification of the norovirus antigenic properties. These data provide new insights into norovirus evolutionary dynamics and indicate new putative epitope "hot-spots" of modified and optimized norovirus-host interactions.

Rituximab for the treatment of membranous nephropathy: a single-center experience.

BACKGROUND: Treatment of idiopathic membranous nephropathy with rituximab was introduced more than a decade ago following experimental data that suggested involvement of B-cell-mediated reactions in its pathogenesis. It was a logical step towards a more selective therapy with less severe side effects as compared to the recommended first-line immunosuppressive therapy with corticosteroids and different immunosuppressant drugs. METHODS: We retrospectively analyzed the anonymous data of patients who were treated with rituximab for idiopathic membranous nephropathy at our institution from January 2006 to July 2016. Daily proteinuria and serum creatinine were analyzed 3, 6, 9, and 12 months after rituximab application. The patients were divided into 4 groups according to proteinuria. We separately analyzed remission rates in the whole group and in groups with different quantity of daily proteinuria. Other history data and laboratory parameters were also compared within different groups of patients. RESULTS: The study involved 29 rituximab treatments in 26 patients: 7 (26.9%) female and 19 (73.1%) male patients. In 16 out of 29 treatment cases (55.1%), patients had been previously treated with cyclophosphamide and steroids, or cyclosporine with low dose of steroids, or both. In 72.4% of patients, antiphospholipase A2 receptor antibodies were present. In 2 cases of treatment (6.9%), patients received rituximab 375 mg/m2 of body surface area in 3 and 4 weekly doses, respectively. In all other cases, repeated rituximab applications were given as needed according to the levels of circulating CD-20 B-cells. The total remission rate in our cohort of patients was 37.9% (11 out of 29 cases). The average serum creatinine in the group of patients who achieved remission was significantly lower than in the group without remission (86.5 vs. 155.5 µmol/L, p = 0.003). There was no difference in the duration of the disease prior to treatment with rituximab between the groups (53.6 and 56.4 months, respectively). The remission rate was highest in the group with daily proteinuria less than 4 g per day (83.3%). There were no remissions in the group of patients with daily proteinuria more than 12 g per day. CONCLUSION: The remission rate after rituximab treatment in our cohort of patients with idiopathic membranous nephropathy was lower than in other studies. The reason for this is possibly the application of a single dose of rituximab in the majority of patients, which might have been insufficient in patients with higher proteinuria.
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Treatment of antibody-mediated rejection of kidney grafts with bortezomib and/or rituximab compared to standard regimen: experience of Slovene National Center.

BACKGROUND: The aim of our study was to determine outcomes of standard treatment of antibody-mediated rejection (ABMR) of kidney grafts as compared to the addition of bortezomib or rituximab. METHODS: The cohort of this retrospective study included patients treated for ABMR of kidney grafts at our national center in the period of 2005 - 2017, divided into two groups: standard (ST) group treated standardly with plasmapheresis or immunoadsorption, intravenous immunoglobulins, and corticosteroids, and BR group treated with the addition of bortezomib and/or rituximab. Patient and graft survival at 2 years was analyzed by Kaplan-Meier method, and predictors of graft survival were analyzed by Cox regression. RESULTS: There were 78 patients with ABMR (48 in the ST group, 30 in the BR group), 41 (53%) were men, mean age 49.5 ± 13.8 years. In ST and BR, respectively, mean serum creatinine was 267 ± 164 and 208 ± 112 µmol/L (p = 0.088), donor-specific antibodies (DSA) were positive in 75% and 97% (p = 0.022), and ABMR was acute in 50% and 33% (p = 0.149). Patient survival at 2 years was 89% in the ST and 100% in the BR group (p = 0.125). Cumulative proportion of kidney graft survival at 1 and 2 years was 67% and 53% in the ST group and 73% and 48% in the BR group, respectively, (p = 0.641). Chronic ABMR (HR 5.22, p = 0.004) was significant, while dialysis dependency at biopsy (HR 3.28, p = 0.072), serum creatinine at kidney biopsy (HR 1.003, p = 0.082), and presence of DQ-DSA (HR 3.37, p = 0.062) were borderline significant predictors of worse graft outcome. Infections were relatively common in both groups, with a trend towards more rehospitalizations due to infections in the first 6 months after treatment in the BR group (p = 0.066). In 5 patients (17%), treatment with bortezomib was discontinued prematurely due to cytopenia. CONCLUSIONS: Bortezomib or rituximab, added to standard treatment, did not significantly improve kidney graft survival and was also not associated with significant side effects, except cytopenia in some cases. Treatment of acute ABMR resulted in better graft survival than chronic ABMR.
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Tubular urinary indexes reliably distinguish between primary tubulointerstitial and primary glomerular diseases in patients referred for kidney biopsy.

AIMS: Kidney biopsy remains the gold standard for accurately diagnosing renal diseases. Urinalysis and assessment of renal function are the cornerstones for assessment of patients prior to biopsy. There is significant overlap in the results of routine urine parameters (proteinuria, erythrocyturia, leukocyturia) among different kidney diseases, which hinders the possibility of adequately estimating disease etiology prior to the biopsy. The aim of our study was to assess whether diverse markers of glomerular and tubular proteinuria - urinary albumin, IgG, α-1-microglobulin (α-1-m) and N-acetyl-ß-D-glucosaminidase (NAG) - are capable of distinguishing between patients with primary tubulointerstitial (TID) and primary glomerular disease (GLOM). METHODS: Our study is a retrospective, single-center, consecutive case series of patients referred for kidney biopsy. We analyzed routine urinalysis results performed on a second morning urine sample immediately prior to the biopsy. RESULTS: Patients with TID had significantly higher values of α-1-m and NAG, with lower values of albumin and IgG in the urine compared to patients with GLOM. Three tubular urinary indexes had high sensitivity and specificity for distinguishing TID from GLOM: NAG/albumin, α-1-m/proteinuria, and α-1-m/albumin, with the highest values in the latter index (96.6% and 98.2%, respectively, cut-off point ≥ 0.33). CONCLUSIONS: Prior to kidney biopsy, tubular urinary indexes may present a valuable tool in distinguishing patients with TID from patients with GLOM.
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Determination of red blood cells in urinary sediment: Do pH and specific gravity of urine matter?

INTRODUCTION: It has been postulated that erythrocyte cell lysis in urine is common in the case of low urine specific gravity and high urine pH. We aimed to verify the influence of urine dipstick pH and specific gravity on erythrocyturia in the urine sediment in the case of positive dipstick hemoglobinuria. METHODS: We retrospectively collected data on dipstick specific gravity, pH, and urine sediment analysis done by nephrologists in the clinical and research urine laboratory at the Department of Nephrology, University Medical Center Ljubljana. RESULTS: During the 6-year observation period, we analyzed 843 second morning midstream urine samples with positive dipstick hemoglobinuria. Erythrocyturia in urinary sediment was detected significantly less often in urine samples with concomitant hemoglobinuria 1+ and pH < 6.0, (odds ratio (OR) 0.40; 95% confidence interval (CI) 0.21 - 0.76, p = 0.005). The difference was maintained in multivariate analysis including patient age, gender, and specific gravity (OR 0.32; 95% CI 0.15 - 0.65, p = 0.002). In samples with higher grade of hemoglobinuria (≥ 2+), the impact of cell lysis in the case of low pH was negligible. Specific gravity did not have any influence on erythrocyte detection in urinary sediment. CONCLUSIONS: Urinary pH < 6.0 impaired the detection of erythrocytes in urinary sediment, while the dipstick measured urine specific gravity did not have any impact on it. Urine samples with low-grade hemoglobinuria and low pH without erythrocyte detection in urinary sediment should be evaluated again to avoid false-negative results.
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Role of dry lean body mass for estimation of glomerular filtration rate in kidney transplant recipients.

BACKGROUND: The use of equations that predict glomerular filtration rate (GFR) in patients with a kidney graft is still a matter of debate. The purpose of this study was to determine the level of accuracy of GFR equations and the relevance of dry lean body mass in the assessment of GFR. METHODS: In a prospective clinical study, 100 patients with a kidney graft were included. Estimated GFR with Modification of Diet in Renal Disease equation (MDRD), Chronic Kidney Disease Epidemiology Collaboration equation (CKD EPI) with serum creatinine concentration (CKD EPI Cr), serum cystatin C concentration (CKD EPI CysC) or both (CKD EPI Cr-CysC), and creatinine clearance calculated with Cockcroft-Gault equation (CG) was compared with GFR measured by 51Cr-EDTA clearance (mGFR 51Cr-EDTA). Dry lean body mass (body mass without fat mass and body water) was measured with bioimpedance analysis. RESULTS: All of the estimating equations overestimated mGFR 51Cr-EDTA by a significant degree (bias ± SD in mL/min/1.73m2, 30% accuracy in brackets): CG 16.8 ± 14.1 (44%), MDRD 12.5 ± 15.3 (54%), CKD EPI Cr 15.1 ± 15.3 (50%), CKD EPI CysC 8.0 ± 16.6 (56%), CKD EPI Cr-CysC 10.3 ± 13.4 (55%). Dry lean body mass significantly correlated with mGFR 51Cr-EDTA, but not with estimated GFRs. CONCLUSION: The estimating GFR equations are neither accurate nor precise in renal transplant recipients. Dry lean body mass is an important parameter that could potentially improve the GFR estimation in this population.
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Prevalence and risk factors for nonvertebral bone fractures in kidney transplant recipients - a single-center retrospective analysis.

BACKGROUND: Complex and longstanding bone disease superimposed by harmful influences of immunosuppression is the reason for increased risk of bone fracture in kidney transplant recipients. The aim of our study was to analyze the incidence and prevalence of nonvertebral bone fractures and early (in the first post-transplant year) clinical and laboratory risk factors for suffering bone fracture in the long-term post-transplant period. METHODS: Clinical and laboratory data as well as bone mineral density (BMD) measurements of 507 first kidney transplant recipients who were transplanted in the period from 1976 to 2011 were analyzed. RESULTS: The mean age of included patients was 54.3 ± 12.0 years, there were 45% females, and mean time on renal replacement treatment prior to transplantation was 63.4 ± 43.6 months. The average observation time post-transplant was 9.7 years (1.4 - 36.3 years). Post-transplant, 64 (12.6%) patients suffered 89 nonvertebral fractures (44 patients suffered 1 fracture, 15 patients 2 fractures, and 5 patients 3 fractures). Patients with fractures had significantly lower late BMD of femoral neck in the period of 1 - 10 years post-transplant, had osteopenia and osteoporosis more frequently in the same time period, and higher serum alkaline phosphatase in the first year post-transplant. 13 patients (13/64, 20.3%) had major fractures. Patients with major fractures were significantly older than patients with no major fractures and had lower serum albumin. Frequency of treatment with bisphosphonate, calcium, or phosphate did not differ between the groups. Vitamin D supplement (active form in 98% of cases) was prescribed more frequently in the group without fractures, but this was not statistically significant. CONCLUSION: Fracture rate in our transplant patient population was comparable to that reported in the literature. Except for a higher level of serum total alkaline phosphatase in the fracture group, we found no other early laboratory risk factors for bone fractures. BMD at the femoral region 1 - 10 years after kidney transplantation but not BMD at the time of transplantation was a risk factor for nonvertebral fractures. Osteopenia and osteoporosis in the post-transplant period were found to be a fracture risk factor.
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Isolated Effects of Renal Failure, Anthropometric Indices, and Serum Total Iron-Binding Capacity as Determinants of Muscle Performance in Hemodialysis Patients.

OBJECTIVE: We quantified the isolated impact of end-stage renal disease (ESRD) on physical performance under contemporary hemodialysis treatment independent of comorbid diseases, characterized principal anthropometric components, and adjusted for their influence and compared associations of C-reactive protein (CRP), albumin, and serum total iron-binding capacity (TIBC) with muscle function. DESIGN: A case-control cross-sectional study. SETTING: University medical hospital and outpatient hemodialysis units. SUBJECTS: Ninety prevalent hemodialysis patients without important comorbidities and 140 controls. MAIN OUTCOME MEASURES: Handgrip strength (HGS) and 10-repetition sit-to-stand time (STS-10). RESULTS: Principal component analysis revealed 3 representative anthropometric measures to be included in explanatory models of muscle performance additional to body height: lean body mass, fat mass, and joint size. Controlling for these covariates, age, sex, and residual comorbidity, ESRD was associated with a modest 7.5% reduction in HGS (B = -2.57 kg; 95% confidence interval: -4.81 to -0.39; P = .005; model R(2) 0.74) and a relatively larger prolongation of 27% in STS-10 time (B = 4s; 95% confidence interval: 2.61 to 5.4; P < .001; model R(2) 0.53). Lean body mass and height significantly predicted both tests, fat mass, and wrist size predicted HGS. In the subgroup of dialysis patients, only TIBC showed a significant association with HGS independently from age, sex, wrist size, whereas CRP and albumin did not. STS-10 time was not associated with any of these biomarkers. Results remained stable in sensitivity analyses excluding patients with reported chronic regional motor difficulties and aches. CONCLUSIONS: ESRD with contemporary hemodialysis therapy has a relatively modest negative comorbidity-free association with HGS and a larger effect on STS-10 lower extremity performance. Nonmodifiable anthropometric indices (body height and for HGS wrist size) have a significant independent impact and should be consistently adjusted for in future studies. In low-comorbidity dialysis patients, TIBC is a superior predictor of HGS compared with albumin and CRP.

Non-inferiority of creatinine excretion rate to urinary L-FABP and NGAL as predictors of early renal allograft function.

BACKGROUND: We evaluated accuracy of urinary liver type fatty acid-binding protein (L-FABP) for prediction of early allograft function and compared it to neutrophil gelatinase associated lipocalin (NGAL), diuresis and urinary creatinine excretion rate (UCr). METHODS: Urine samples from 71 consecutive patients were taken 4, 10, 24 and 48 h after transplantation. We classified recipients into two groups: immediate graft function (IGF), with more than 70% reduction of serum Cr at 7th day post-transplant, and delayed graft function (DGF)/slow graft function (SGF) group (DGF--the need for hemodialysis procedure in the first week, SGF--less than 70% reduction of serum Cr in the first week). RESULTS: Thirty-one recipients had IGF and 40 had DGF/SGF. L-FABP was only useful 48 h post-transplant with ROC AUC of 0.85 (95% C.I. 0.74-0.92); NGAL 24 h post-transplant had ROC AUC of 0.82 (0.7-0.91). Sensitivity, specificity, PPV and NPV for prediction of DGF/SGF with L-FABP > 9.5 mg/mmol Cr and NGAL > 33.1 µg/mmol Cr were: 86, 80, 83 and 83% (L-FABP), and 68, 93, 91, and 73% (NGAL). The difference in urine output between the groups was largest 4 h post-transplant (p = 0.001), later on the difference diminished. There were no significant differences in ROC AUC between L-FABP at 48 h, NGAL at 24 h, urine output at 4 h and UCr excretion rate at 10 h post-transplant. UCr < 0.56 mmol/h 10 h post-transplant predicted DGF/SGF with 94% sensitivity, 84% specificity, 89% PPV and 91% NPV, ROC AUC was 0.9. Classification tree with urine output 4 h and UCr 10 h post-transplant accurately predicted 89% of outcomes. When L-FABP or NGAL were added, the prediction was accurate in 92 or 90%, respectively. CONCLUSIONS: L-FABP is comparable to NGAL for prediction of first week allograft function, however UCr and diuresis were non-inferior.

Serum with phospholipase A2 receptor autoantibodies interferes with podocyte adhesion to collagen.

BACKGROUND: The majority of sera from patients with primary membranous nephropathy have autoantibodies against the M-type phospholipase A2 receptor (PLA2R) which is expressed on human podocytes. The rabbit variant of PLA2R attaches to collagen type IV via the fibronectin type II domain, which is also present in the human variant of PLA2R. DESIGN: To assess whether the human PLA2R variant is also involved in attachment to collagen type IV, we conducted a cell adhesion assay on a collagen-coated surface using PLA2R-transfected and mock-transfected human embryonic kidney (HEK) cells. To test the hypothesis that sera from patients containing anti-PLA2R antibodies interfere with the adhesion of podocytes to collagen, we performed cell adhesion assays on a collagen type IV-coated surface using positive and negative serum samples from patients and cultured human podocytes in vitro expressing PLA2R. RESULTS: The HEK cell adhesion assay confirmed an enhanced attachment of PLA2R-transfected cells to collagen type IV. We confirmed diminished podocyte adhesion in the presence of serum with anti-PLA2R antibodies. The concentration of anti-PLA2R antibodies correlated with proteinuria and to the degree of diminished adhesion of podocytes. CONCLUSIONS: We demonstrated that serum of patients containing autoantibodies directed to PLA2R interferes with the ability of podocytes to attach to collagen type IV in vitro, providing evidence of a serum soluble pathogenic factor interfering with podocyte adhesion in membranous nephropathy.

Urinary immunoglobulin G to albumin ratio and N-Acetyl-Beta-D-Glucosaminidase as early predictors of therapeutic response in ANCA-associated glomerulonephritis.

BACKGROUND: The aim of our study was to evaluate the prognostic value of glomerular and tubular proteinuria and tubular enzymuria as early indicators of therapeutic response to induction therapy with i.v. pulse cyclophosphamide (CyC) and methylprednisolone (MP) in patients with antineutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis. METHODS AND FINDINGS: An observational single-center study was conducted in 30 patients with ANCA-associated glomerulonephritis. Patients were divided into subgroups with good or poor response to CyC therapy according to clinical and laboratory parameters. The diagnosis of ANCA-associated glomerulonephritis was based on the Chapel-Hill disease definitions. Good response to induction therapy was significantly associated with higher absolute values of urine N-acetyl-beta-D-glucosaminidase (NAG) to creatinine ratio (above 14.83 microcat/mol) and urine immunoglobulin G (IgG) to albumin ratio (above 0.09) at the time of diagnosis, while albuminuria or proteinuria did not have any early predictive value. The remission of renal disease was anticipated as early as 3 months after introduction of induction therapy in patients with reduction of urine NAG to creatinine ratio below the baseline value and in patients with at least 24% rise in eGFR. CONCLUSIONS: Urine IgG to albumin and urine NAG to creatinine ratio are better early predictors of treatment response in patients with ANCA-associated glomerulonephritis than proteinuria or albuminuria.

An anti-phospholipase A2 receptor quantitative immunoassay and epitope analysis in membranous nephropathy reveals different antigenic domains of the receptor.

The phospholipase A2 receptor (PLA2R) was recently discovered as a target autoantigen in patients with idiopathic membranous nephropathy (IMN). Published evidence suggests that the autoantibodies directed towards a conformation dependent epitope are currently effectively detected by a cell based assay (CBA) utilizing indirect immunofluorescence (IIF) on tissue culture cells transfected with the PLA2R cDNA. Limitations of such IIF-CBA assays include observer dependent subjective evaluation of semi-quantitative test results and the protocols are not amenable to high throughput diagnostic testing. We developed a quantitative, observer independent, high throughput capture immunoassay for detecting PLA2R autoantibodies on an addressable laser bead immunoassay (ALBIA) platform. Since reactive domains of PLA2R (i.e. epitopes) could be used to improve diagnostic tests by using small peptides in various high throughput diagnostic platforms, we identified PLA2R epitopes that bound autoantibodies of IMN patients. These studies confirmed that inter-molecular epitope spreading occurs in IMN but use of the cognate synthetic peptides in immunoassays was unable to conclusively distinguish between IMN patients and normal controls. However, combinations of these peptides were able to effectively absorb anti-PLA2R reactivity in IIF-CBA and an immunoassay that employed a lysate derived from HEK cells tranfected with and overexpressing PLA2R. While we provide evidence of intermolecular epitope spreading, our data indicates that in addition to conformational epitopes, human anti-PLA2R reactivity in a commercially available CBA and an addressable laser bead immunoassay is significantly absorbed by peptides representing epitopes of PLA2R.