Computable phenotype for real-world, data-driven retrospective identification of relapse in ANCA-associated vasculitis.

OBJECTIVE: ANCA-associated vasculitis (AAV) is a relapsing-remitting disease, resulting in incremental tissue injury. The gold-standard relapse definition (Birmingham Vasculitis Activity Score, BVAS>0) is often missing or inaccurate in registry settings, leading to errors in ascertainment of this key outcome. We sought to create a computable phenotype (CP) to automate retrospective identification of relapse using real-world data in the research setting. METHODS: We studied 536 patients with AAV and >6 months follow-up recruited to the Rare Kidney Disease registry (a national longitudinal, multicentre cohort study). We followed five steps: (1) independent encounter adjudication using primary medical records to assign the ground truth, (2) selection of data elements (DEs), (3) CP development using multilevel regression modelling, (4) internal validation and (5) development of additional models to handle missingness. Cut-points were determined by maximising the F1-score. We developed a web application for CP implementation, which outputs an individualised probability of relapse. RESULTS: Development and validation datasets comprised 1209 and 377 encounters, respectively. After classifying encounters with diagnostic histopathology as relapse, we identified five key DEs; DE1: change in ANCA level, DE2: suggestive blood/urine tests, DE3: suggestive imaging, DE4: immunosuppression status, DE5: immunosuppression change. F1-score, sensitivity and specificity were 0.85 (95% CI 0.77 to 0.92), 0.89 (95% CI 0.80 to 0.99) and 0.96 (95% CI 0.93 to 0.99), respectively. Where DE5 was missing, DE2 plus either DE1/DE3 were required to match the accuracy of BVAS. CONCLUSIONS: This CP accurately quantifies the individualised probability of relapse in AAV retrospectively, using objective, readily accessible registry data. This framework could be leveraged for other outcomes and relapsing diseases.

Capacity for the management of kidney failure in the International Society of Nephrology Eastern and Central Europe region: report from the 2023 ISN Global Kidney Health Atlas (ISN-GKHA).

Delivery of care for kidney failure (KF) globally has a significant disparity; even in some countries, it means end of life for the person. The International Society of Nephrology Global Kidney Health Atlas (ISN-GKHA) tries to address gaps in KF care and standardize global nephrology care. From the third iteration of the ISN-GKHA, we present data for countries in the ISN Eastern and Central Europe region. The median prevalences of chronic kidney disease (12.8%) and treated KF (873.5 pmp) were higher than the global rates, respectively. Hemodialysis was the most preferred modality for KF in adults, whereas kidney replacement therapy was more balanced in children. Although most of the countries in the region had lower-middle-income and upper-middle-income levels, health expenditures for kidney health care were almost generally covered publicly. Nephrologists were responsible for the medical kidney care of people with KF in all countries. There was adequate infrastructure to provide all kinds of treatment for kidney care in the region. Regional characteristics such as high levels of obesity, smoking, and Balkan nephropathy as an endemic disease coupled with a shortage of workforce and finance continued to affect kidney care in the region negatively. By making organizational and legislative arrangements, partnerships with national authorities and societies may accelerate the improvement of kidney health care in the region.

A novel dosing approach for rituximab in glomerular diseases based on a population pharmacokinetic analysis.

OBJECTIVES: Rituximab is being increasingly prescribed for the treatment of autoimmune glomerular diseases. While it is highly effective for some diseases, the response is less predictable for others, which may be due to differing requirements in terms of the dosing according to the disease type and variations concerning exposure to the drug. METHODS: We compiled novel rituximab dosing schedules according to pharmacokinetic analysis of data gathered from rituximab treated patients in a tertiary referral nephrology centre between May 2020 and June 2023. The population-pharmacokinetic analysis was based on the rituximab dosing, the patients' characteristics, rituximab levels and anti-rituximab antibodies. RESULTS: The analysis, which was based on data from 185 patients, clearly highlighted differing rituximab dosing requirements for patients with ANCA associated vasculitis and minimal change disease compared to those with membranous nephropathy, focal-segmental glomerulosclerosis and lupus nephritis. This corresponded to the good treatment response of the first two diseases and the unreliable efficacy for the others. The model predicts the rituximab pharmacokinetics with high degree of accuracy when body weight, proteinuria, type of glomerulonephritis, treatment length and anti-rituximab antibodies formation are used as covariates. We proposed a dosing schedule with shortened dosing intervals for difficult-to-treat diagnoses with high proteinuria. CONCLUSION: In order to ensure reliable and comparable exposure of rituximab with respect to the full range of glomerular diseases, the dosing schedule should be adjusted for membranous nephropathy, focal-segmental glomerulosclerosis and lupus nephritis. This is largely, but not solely, due to the enhanced level of unselective proteinuria in these diseases.

Increased Cardiovascular Risk in Young Patients with CKD and the Role of Lipid-Lowering Therapy.

PURPOSE OF REVIEW: Chronic kidney disease (CKD) is associated with a significantly increased risk of cardiovascular disease (CVD). This review summarizes known risk factors, pathophysiological mechanisms, and current therapeutic possibilities, focusing on lipid-lowering therapy in CKD. RECENT FINDINGS: Novel data on lipid-lowering therapy in CKD mainly stem from clinical trials and clinical studies. In addition to traditional CVD risk factors, patients with CKD often present with non-traditional risk factors that include, e.g., anemia, proteinuria, or calcium-phosphate imbalance. Dyslipidemia remains an important contributing CVD risk factor in CKD, although the mechanisms involved differ from the general population. While statins are the most commonly used lipid-lowering therapy in CKD patients, some statins may require dose reduction. Importantly, statins showed diminished beneficial effect on cardiovascular events in patients with severe CKD and hypercholesterolemia despite high CVD risk and effective reduction of LDL cholesterol. Ezetimibe enables the reduction of the dose of statins and their putative toxicity and, in combination with statins, reduces CVD endpoints in CKD patients. The use of novel drugs such as PCSK9 inhibitors is safe in CKD, but their potential to reduce cardiovascular events in CKD needs to be elucidated in future studies.

Long-term outcome of kidney function in patients with ANCA-associated vasculitis.

BACKGROUND: Kidney involvement is common in ANCA associated vasculitis (AAV) and prognosis determined by the severity of kidney damage. This study focused on long-term kidney outcomes, defining possible risk factors and comparing the performance of three different histological classifications to predict outcomes for patients with AAV. METHODS: The dataset included 848 patients with newly diagnosed AAV who participated in 7 RCTs (1995-2012). Follow up information obtained from questionnaires sent to the principal investigators of the original RCTs. RESULTS: The cumulative incidence of end-stage kidney disease (ESKD) at 5 and 10 years was 17% and 22%, respectively. Patients who developed ESKD had reduced patient survival compared to those with preserved kidney function (HR: 2.8, P-value < 0.001). Comparing patients with AAV and kidney involvement to a matched general population, patients with AAV had poor survival outcomes, even in early stages of CKD. The main cause of death was infection followed by cardiovascular disease in patients developing ESKD and malignancy in those who did not. 34% of patients with initial need for dialysis recovered kidney function after treatment. 35 out of 175 in need of kidney replacement therapy (KRT) during follow up received a kidney transplant with good outcome; 86% patient survival at 10 years.In the subcohort of 214 patients with available kidney biopsies, three scoring systems were tested: the Berden classification, the Renal Risk Score (RRS), and the Mayo Clinic Score (MCCS). The scores highlighted the importance of normal glomeruli and severe glomerulosclerosis on kidney survival (P < 0.001 and P = 0.001, respectively). The RRS demonstrated a moderate prediction of kidney survival (AUC: 0.79; SE: 0.03, 95% CI: 0.71-0.83). CONCLUSIONS: Early diagnosis is extremely important. Even milder forms of kidney involvement have an impact on the prognosis. Patients in need of KRT had the lowest survival rates, but kidney transplantation has shown favorable outcomes for eligible AAV patients. The three histologic scoring systems were all identified as independent prognostic factors for kidney outcome.

Nephrology Partnership for Advancing Technology in Healthcare (N-PATH) program: the teachers' perspective.

The N-PATH (Nephrology Partnership for Advancing Technology in Healthcare) program concluded with the 60th European Renal Association 2023 Congress in Milan, Italy. This collaborative initiative aimed to provide advanced training in interventional nephrology to young European nephrologists. Funded by Erasmus+ Knowledge Alliance, N-PATH addressed the global burden of chronic kidney disease (CKD) and the shortage of nephrologists. CKD affects >850 million people worldwide, yet nephrology struggles to attract medical talent, leading to unfilled positions in residency programs. To address this, N-PATH focused on enhancing nephrology education through four specialized modules: renal expert in renal pathology (ReMAP), renal expert in vascular access (ReVAC), renal expert in medical ultrasound (ReMUS) and renal expert in peritoneal dialysis (RePED). ReMAP emphasized the importance of kidney biopsy in nephrology diagnosis and treatment, providing theoretical knowledge and hands-on training. ReVAC centred on vascular access in haemodialysis, teaching trainees about different access types, placement techniques and managing complications. ReMUS recognized the significance of ultrasound in nephrology, promoting interdisciplinary collaboration and preparing nephrologists for comprehensive patient care. RePED addressed chronic peritoneal dialysis, offering comprehensive training in patient selection, prescription, monitoring, complications and surgical techniques for catheter insertion. Overall, N-PATH's strategy involved collaborative networks, hands-on training, mentorship, an interdisciplinary approach and the integration of emerging technologies. By bridging the gap between theoretical knowledge and practical skills, N-PATH aimed to revitalize interest in nephrology and prepare proficient nephrologists to tackle the challenges of kidney diseases. In conclusion, the N-PATH program aimed to address the shortage of nephrologists and improve the quality of nephrology care in Europe. By providing specialized training, fostering collaboration and promoting patient-centred care, N-PATH aimed to inspire future nephrology professionals to meet the growing healthcare demands related to kidney diseases and elevate the specialty's status within the medical community.

Elimination and penetration of amikacin into urine in patients with decreased glomerular filtration rate.

Background: Amikacin monotherapy is recommended for urinary tract infection (UTI) treatment with multi-resistant pathogens. Even though amikacin efficacy in the treatment of UTIs is dependent on its urinary concentration, there are no robust data proving that sufficiently high urinary concentration is reached in patients with reduced glomerular filtration rate (GFR). Methods: A prospective study to monitor amikacin penetration into urine of 70 patients [40 males, median (interquartile range) age 70 (65-79) years] with different levels of glomerular filtration decline, including patients treated by dialysis, was conducted. The bactericidal efficacy of amikacin in urine samples has been evaluated. Results: Patients with estimated GFR (eGFR) <30 mL/min had significantly lower median amikacin urinary concentration than patients with eGFR >30 mL/min (89.75 vs 186.0 mg/L, P < .0001; 200.5 vs 830.0 mg/L, P < .0001; and 126.0 vs 408.0 mg/L, P < .0001 for minimal, maximal and minimal together with maximal concentrations, respectively). The amount of amikacin eliminated in the first 10-13 h after dose administration was dependent on eGFR (r2 = 0.6144, P < .0001). The urinary concentration of amikacin in patients treated by dialysis was indirectly proportional to pH of urine. The plasma concentrations of amikacin did not correlate with urinary levels in patients in either of the GFR categories. Microbiological evaluation showed that the critical urinary concentration for efficacy of amikacin during UTI monotherapy in patients treated by dialysis is 100 mg/L. We found that 4 out of 11 patients treated by dialysis did not reach this level during the treatment. Conclusion: Systemic administration of amikacin monotherapy in patients treated by dialysis is questionable as the concentrations of amikacin in their urine are often below the threshold of effectivity. Amikacin plasma concentrations are not a major determinant of amikacin concentration in urine, therefore pulse dosing is neither necessary nor safe in patients treated by dialysis, and may cause undesirable toxicity.

Data quality and patient characteristics in European ANCA-associated vasculitis registries: data retrieval by federated querying.

OBJECTIVES: This study aims to describe the data structure and harmonisation process, explore data quality and define characteristics, treatment, and outcomes of patients across six federated antineutrophil cytoplasmic antibody-associated vasculitis (AAV) registries. METHODS: Through creation of the vasculitis-specific Findable, Accessible, Interoperable, Reusable, VASCulitis ontology, we harmonised the registries and enabled semantic interoperability. We assessed data quality across the domains of uniqueness, consistency, completeness and correctness. Aggregated data were retrieved using the semantic query language SPARQL Protocol and Resource Description Framework Query Language (SPARQL) and outcome rates were assessed through random effects meta-analysis. RESULTS: A total of 5282 cases of AAV were identified. Uniqueness and data-type consistency were 100% across all assessed variables. Completeness and correctness varied from 49%-100% to 60%-100%, respectively. There were 2754 (52.1%) cases classified as granulomatosis with polyangiitis (GPA), 1580 (29.9%) as microscopic polyangiitis and 937 (17.7%) as eosinophilic GPA. The pattern of organ involvement included: lung in 3281 (65.1%), ear-nose-throat in 2860 (56.7%) and kidney in 2534 (50.2%). Intravenous cyclophosphamide was used as remission induction therapy in 982 (50.7%), rituximab in 505 (17.7%) and pulsed intravenous glucocorticoid use was highly variable (11%-91%). Overall mortality and incidence rates of end-stage kidney disease were 28.8 (95% CI 19.7 to 42.2) and 24.8 (95% CI 19.7 to 31.1) per 1000 patient-years, respectively. CONCLUSIONS: In the largest reported AAV cohort-study, we federated patient registries using semantic web technologies and highlighted concerns about data quality. The comparison of patient characteristics, treatment and outcomes was hampered by heterogeneous recruitment settings.

The frequency of, and predisposing risk factors for, ciprofloxacin-induced neuro-psychiatric adverse drug reactions.

OBJECTIVES: Ciprofloxacin induces rare neuro-psychiatric adverse drug reactions (ADRs) that are, as yet, not possible to predict due to unknown predisposition factors. BACKGROUND: The aim of the analysis was to assess the frequency of neuro-psychiatric ADRs and to identify potential risk factors that predisposed patients to ciprofloxacin neurotoxicity. METHODS: This observational retrospective study involved the evaluation of the medical records of patients in the Nephrology department and 3rd Internal Clinic of the General University Hospital in Prague. RESULTS: The overall incidence of neurological ADRs was 3.6 %. No neurological ADRs developed in patients aged less than 70 years. The covariates that were significantly more prevalent in the patients who developed neuropsychiatric ADRs were as follows: higher age, a history of neuropsychiatric disorders and the use of anticonvulsants. The administration of drugs from other ATC groups, gender, weight, body mass index, body surface area, renal functions, level of C-reactive protein at the beginning of treatment and the total daily dose/kg did not differ significantly between the two groups. CONCLUSION: Ciprofloxacin neuropsychiatric ADRs are more frequent in older patients with a history of neurologic or psychiatric disorders. No other tested covariates were proven to predispose patients to neuropsychiatric ADRs during treatment with ciprofloxacin (Tab. 2, Ref. 20).

Unique Biomarkers of Collagen Type III Remodeling Reflect Different Information Regarding Pathological Kidney Tissue Alterations in Patients with IgA Nephropathy.

Kidney fibrosis is the hallmark of chronic kidney disease (CKD) and is characterized by an imbalanced extracellular matrix (ECM) remodeling. Collagen type III is one of the main ECM components of the interstitial matrix of the kidney. We hypothesized that measuring three biomarkers of collagen type III reflecting different aspects of this protein turnover (C3M, C3C, and PRO-C3) may provide different information about the fibrotic burden in patients with IgA nephropathy (IgAN). We examined a cohort of 134 patients with IgAN. The three collagen type III biomarkers were measured in serum (S) and in urine (U) samples taken on the same day before kidney biopsy was performed. Biopsies were evaluated for interstitial fibrosis and tubular atrophy, according to the Banff and MEST-C scores. S-PRO-C3 and S-C3C correlated with the degree of fibrosis in the biopsy, whereas U-C3M/Cr had an inverse correlation with fibrosis. U-C3M/Cr had the highest discrimination ability for advanced fibrosis, which was maintained after adjustment for the other collagen type III biomarkers, proteinuria, and serum creatinine. The data presented in this study indicate that measuring the different fragments of the same ECM protein and in different matrices provides a variety of information regarding pathological kidney tissue alterations in patients with IgAN.

Heart failure with preserved ejection fraction is the most frequent but commonly overlooked phenotype in patients on chronic hemodialysis.

Introduction: Heart failure (HF) is a serious complication of end-stage kidney disease (ESKD). However, most data come from retrospective studies that included patients on chronic hemodialysis at the time of its initiation. These patients are frequently overhydrated, which significantly influences the echocardiogram findings. The primary aim of this study was to analyze the prevalence of heart failure and its phenotypes. The secondary aims were (1) to describe the potential of N-terminal pro-brain natriuretic peptide (NTproBNP) for HF diagnosis in ESKD patients on hemodialysis, (2) to analyze the frequency of abnormal left ventricular geometry, and (3) to describe the differences between various HF phenotypes in this population. Methods: We included all patients on chronic hemodialysis for at least 3 months from five hemodialysis units who were willing to participate, had no living kidney transplant donor, and had a life expectancy longer than 6 months at the time of inclusion. Detailed echocardiography together with hemodynamic calculations, dialysis arteriovenous fistula flow volume calculation, and basic lab analysis were performed in conditions of clinical stability. Excess of severe overhydration was excluded by clinical examination and by employing bioimpedance. Results: A total of 214 patients aged 66.4 ± 14.6 years were included. HF was diagnosed in 57% of them. Among patients with HF, HF with preserved ejection fraction (HFpEF) was, by far, the most common phenotype and occurred in 35%, while HF with reduced ejection fraction (HFrEF) occurred only in 7%, HF with mildly reduced ejection fraction (HFmrEF) in 7%, and high-output HF in 9%. Patients with HFpEF differed from patients with no HF significantly in the following: they were older (62 ± 14 vs. 70 ± 14, p = 0.002) and had a higher left ventricular mass index [96(36) vs. 108(45), p = 0.015], higher left atrial index [33(12) vs. 44(16), p < 0.0001], and higher estimated central venous pressure [5(4) vs. 6(8), p = 0.004] and pulmonary artery systolic pressure [31(9) vs. 40(23), p = 0.006] but slightly lower tricuspid annular plane systolic excursion (TAPSE): 22 ± 5 vs. 24 ± 5, p = 0.04. NTproBNP had low sensitivity and specificity for diagnosing HF or HFpEF: with the use of the cutoff value of 8,296 ng/L, the sensitivity of HF diagnosis was only 52% while the specificity was 79%. However, NTproBNP levels were significantly related to echocardiographic variables, most significantly to the indexed left atrial volume (R = 0.56, p < 10-5) and to the estimated systolic pulmonary arterial pressure (R = 0.50, p < 10-5). Conclusions: HFpEF was by far the most common heart failure phenotype in patients on chronic hemodialysis and was followed by high-output HF. Patients suffering from HFpEF were older and had not only typical echocardiographic changes but also higher hydration that mirrored increased filling pressures of both ventricles than in those of patients without HF.

Biomarkers of fibrosis, kidney tissue injury and inflammation may predict severity and outcome of renal ANCA - associated vasculitis.

Background: Activity and chronicity of kidney involvement in ANCA-associated vasculitis (AAV) can be currently reliably evaluated only by kidney biopsy. In this study, we measured a panel of serum and urinary biomarkers collected at the time of kidney biopsy and hypothesized that they could reflect specific histopathological parameters in the biopsy and help to predict prognosis. Methods: We examined a cohort of 45 patients with AAV and 10 healthy controls. Biomarker levels (DKK-3, CD163, EGF, PRO-C6 and C3M) were measured in this study by ELISA. Biopsies were scored with a scoring system for AAV (focal x crescentic x sclerotic x mixed class) and interstitial fibrosis was quantified. Results: Levels of urinary DKK-3, CD163, EGF, PRO-C6 and C3M significantly differed among biopsy classes in AAV, with urinary DKK-3 and PRO-C6 levels being highest in the sclerotic class and lowest in the focal class, urinary CD163 levels highest in the crescentic class and urinary C3M levels highest in the focal class. Moreover, the urinary biomarkers were able to discriminate focal biopsy class from the other classes. Urinary DKK-3, EGF, PRO-C6 and C3M levels measured at the time of biopsy were also significantly related to the extent of fibrosis and to the final kidney function at the end of follow-up. Conclusions: This small pilot study suggests that selected urinary biomarkers of fibrosis and inflammation may reflect changes in the kidney biopsy and be prognostic of kidney outcome in patients with AAV.

Serum and Urine Biomarkers Related to Kidney Fibrosis Predict Kidney Outcome in Czech Patients with IgA Nephropathy.

We evaluated biomarkers related to kidney fibrosis for the outcome of patients with IgA nephropathy (IgAN). Clinical parameters (estimated glomerular filtration rate, hypertension, proteinuria) and histological findings were assessed in 134 patients with IgAN at the time of diagnosis and followed up prospectively (mean follow-up time, 56.5 months). We measured biomarkers of collagen and laminin turnover in serum and urine collected at the time of kidney biopsy using a novel enzyme-linked immunosorbent assay. Linear discriminant analysis and logistic regression models were used to predict the patient's kidney outcome. Five serum and urine biomarkers of laminin and collagen turnover (sLG1M, sPRO-C3, sPRO-C6, uPRO-C6/Cr, uC3M/Cr) could significantly differentiae IgAN patients with a worse prognosis. Clinical parameters (glomerular filtration rate (GFR), proteinuria) distinguished patients at risk of IgAN progression with a specificity of 87.3% and a sensitivity of 45.2% (area under the curve-AUC 0.751). The addition of the biomarkers significantly increased the prognostic ability with a specificity of 85.1% and a sensitivity of 73.3% (AUC 0.905). We have identified three serum (sLG1M, sPRO-C3, sPRO-C6) and two urinary markers (uPRO-C6/Cr, u-C3M /Cr) that significantly improve the prognostic ability of markers of kidney function to identify an IgAN patient's risk of progressing to ESKD.

Traditional and Disease-Specific Risk Factors for Cardiovascular Events in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A Multinational Retrospective Study.

OBJECTIVE: To investigate the occurrence of cardiovascular events (CVEs) in a large cohort of patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) across the European Union, China, Turkey, Russia, the United Kingdom, and the USA. METHODS: Patients with a definite diagnosis of AAV who were followed for ≥ 3 months and had sufficient documentation were included. Data on myocardial infarction (MI) and stroke were collected retrospectively from tertiary vasculitis centers. Univariate and multivariate Cox regression models were used to estimate hazard ratios (HRs) and 95% CIs. RESULTS: Over a median follow-up of 62.0 months (IQR 22.6-100.0), CVEs (mostly MIs) occurred in 245 (10.7%) of 2286 patients with AAV, with a higher frequency in China and the UK. On multivariate regression analysis, older age (55-64.9 yrs, HR 2.93, 95% CI 1.99-4.31), smoking (HR 1.98, 95% CI 1.48-2.64), Chinese origin (HR 4.24, 95% CI 3.07-5.85), and pulmonary (HR 1.50, 95% CI 1.09-2.06) and kidney (HR 3.02, 95% CI 2.08-4.37) involvement were independent variables associated with a higher occurrence of CVEs. CONCLUSION: We showed that geographic region and both traditional and disease-specific (kidney involvement in particular) factors were independently associated with CVEs. Proper assessment and management of modifiable cardiovascular (CV) risk factors are essential for prevention of CV morbidity in patients with AAV.

Long-term outcomes and prognostic factors for survival of patients with ANCA-associated vasculitis.

BACKGROUND: Despite newer treatments with immunosuppressive agents, there still exists a considerable morbidity and mortality risk among patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Since 1994 the European Vasculitis Society (EUVAS) has aimed for an improved outcome for patients with AAV, conducting several prospective randomized controlled trials (RCTs). The aim for the present study was to further evaluate the long-term survival of patients with AAV included in seven RCTs conducted by the EUVAS as well as to identify potential prognostic factors. METHODS: Long-term follow-up data were collected from questionnaires sent to the principal investigators of the original RCTs (1995-2012): MEPEX, NORAM, CYCAZAREM, CYCLOPS, IMPROVE, RITUXVAS and MYCYC, comprising 848 patients, all newly diagnosed with AAV. Relative survival estimates are presented for the study cohorts. Demographic, clinical and laboratory characteristics at trial entry were studied as potential prognostic factors in multivariable models. RESULTS: A total of 478 (56%) patients had granulomatosis with polyangiitis (GPA) and 370 (44%) had microscopic polyangiitis (MPA) with a mean age at diagnosis of 58 ± 14 years. The median follow-up time was 8 years (interquartile range 2.9-13.6). During the observation period there were 305 deaths and the main causes were infections (26%), cardiovascular disease (14%) and malignancies (13%). When compared with a matched cohort (regarding country, age group and sex) from the background population there were 14.2% more deaths among our cohort of AAV patients at 5 years, 19.9% at 10 years, 28.8% at 15 years and 36.3% at 20 years. The excess mortality occurred in all age groups. The estimated median survival time (from diagnosis) was 17.8 years (95% confidence interval 15.7-20). Among variables measured at baseline, advanced age, male sex, low estimated glomerular filtration rate and low platelet count were identified as predictors of death in a multivariate Cox model. CONCLUSIONS: Patients with AAV still have an increased risk of mortality compared with the general population despite newer therapeutic regimens. Treatment complications and organ damage are the main causes of limited survival and infections remain the leading cause of mortality among patients with AAV.

Predictors of hypogammaglobulinemia in ANCA-associated vasculitis after a rituximab-based induction: a multicentre study.

OBJECTIVES: Rituximab has become the cornerstone of induction treatment in ANCA-associated vasculitis (AAV). B-cell depletion may increase the risk of hypogammaglobulinemia, potentially leading to severe infections. This study aims to assess factors associated with hypogammaglobulinemia in AAV patients treated with rituximab. METHODS: This retrospective cohort study included AAV patients treated with rituximab induction in 14 European centres. Severe adverse events (SAEs) were defined as episodes requiring hospitalization or intravenous antibiotics, malignancies, or death. Linear and logistic regression were used to identify predictors of IgG levels and of the risk of hypogammaglobulinemia, defined as IgG ≤7 g/l at 6 months. RESULTS: The study included 227 patients. IgG levels at 6 months were lower than baseline (P < 0.001). Patients requiring intravenous antibiotics during the first 6 months had lower IgG levels at 6 months (P = 0.004). Age [ß (95% CI): -0.23 (-0.38, -0.08) per 10 years, P = 0.003], oral glucocorticoid dose at induction [ß (95% CI): -0.37 (-0.51, -0.24) per sqrt-transformed mg prednisone, P < 0.001] and concomitant use of intravenous glucocorticoid pulses [ß (95% CI): -0.88 (-1.73, -0.02), P = 0.044] were associated with IgG levels at 6 months. Hypogammaglobulinemia was identified in 97 (42.7%) patients. In multivariable logistic regression, factors associated with the risk of hypogammaglobulinemia were age [OR (95% CI): 1.46 (1.15, 1.86) per 10 years, P = 0.002] and oral glucocorticoid dose at induction [OR (95% CI): 1.52 (1.23, 1.89) per 10 mg prednisone, P < 0.001]. CONCLUSIONS: In AAV patients treated with rituximab, hypogammaglobulinemia at 6 months after induction is common, and lower IgG levels are associated with serious infections. The risk of hypogammaglobulinemia in these patients increases with age and higher glucocorticoid doses.

Implications of rituximab pharmacokinetic and pharmacodynamic alterations in various immune-mediated glomerulopathies and potential anti-CD20 therapy alternatives.

The specific B-cell depleting anti-CD20 monoclonal antibody rituximab (RTX) is effective in terms of the treatment of various immune-mediated glomerulopathies. The administration of RTX has been shown to be reliable and highly effective particularly in patients with ANCA-associated vasculitis, which is manifested predominantly with non-nephrotic proteinuria. Stable long-term B-cell depletion is usually readily attained in such patients using standard dosing regimens. However, in patients with nephrotic syndrome and non-selective proteinuria, the RTX pharmacokinetics is altered profoundly and RTX does not maintain high enough levels for a sufficiently long period, which may render RTX treatment ineffective. Since complement-derived cytotoxicity is one of the important modes of action of RTX, hypocomplementemia, frequently associated with systemic lupus erythematodes, may act to hamper the efficacy of RTX in the treatment of patients with lupus nephritis. This review provides a description of RTX pharmacokinetics and pharmacodynamics in several selected glomerulopathies, as well as the impact of proteinuria, anti-drug antibodies and other clinical variables on the clearance and volume of distribution of RTX. The impact of plasmapheresis and peritoneal dialysis on the clearance of RTX is also discussed in the paper. A review is provided of the potential association between pharmacokinetic and pharmacodynamic alterations in various kidney-affecting glomerular diseases, the sustainability of B-cell depletion and the clinical efficacy of RTX, with proposals for potential dosing implications. The role of therapeutic drug monitoring in treatment tailoring is also discussed, and various previously tested RTX dosing schedules are compared in terms of their clinical and laboratory treatment responses. Since alternative anti-CD20 molecules may prove effective in RTX unresponsive patients, their pharmacokinetics, pharmacodynamics and current role in the treatment of glomerulopathies are also mentioned.

Complement Inhibition in ANCA-Associated Vasculitis.

Efficacy of immunosuppressive treatment of Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is complicated by its toxicity. With the replacement of cyclophosphamide with rituximab, serious adverse events seem to be associated especially with high-dose corticosteroids. Activation of alternative complement pathway plays an important role in the pathogenesis of AAV. Avacopan (C5a receptor inhibitor) was demonstrated to have at least similar efficacy and better safety (in terms of corticosteroid-related adverse events) compared with high-dose corticosteroids in the induction treatment of AAV. Other modes of the inhibition of alternative complement pathway are currently tested in AAV or could be considered on the basis of the experience in other glomerular diseases.

CZecking heart failure in patients with advanced chronic kidney disease (Czech HF-CKD): Study protocol.

BACKGROUND: Heart failure (HF) is a frequent cause of morbidity and mortality of end-stage kidney disease (ESKD) patients on hemodialysis. It is not easy to distinguish HF from water overload. The traditional HF definition has low sensitivity and specificity in this population. Moreover, many patients on hemodialysis have exercise limitations unrelated to HF. Therefore, we postulated two new HF definitions ((1) Modified definition of the Acute Dialysis Quality Improvement working group; (2) Hemodynamic definition based on the calculation of the effective cardiac output). We hypothesize that the newer definitions will better identify patients with higher number of endpoints and with more advanced structural heart disease. METHODS: Cohort, observational, longitudinal study with recording predefined endpoints. Patients (n = 300) treated by hemodialysis in six collaborating centers will be examined centrally in a tertiary cardiovascular center every 6-12 months lifelong or till kidney transplantation by detailed expert echocardiography with the calculation of cardiac output, arteriovenous dialysis fistula flow volume calculation, bio-impedance, and basic laboratory analysis including NTproBNP. Effective cardiac output will be measured as the difference between measured total cardiac output and arteriovenous fistula flow volume and systemic vascular resistance will be also assessed non-invasively. In case of water overload during examination, dry weight adjustment will be recommended, and the patient invited for another examination within 6 weeks. A composite major endpoint will consist of (1) Cardiovascular death; (2) HF worsening/new diagnosis of; (3) Non-fatal myocardial infarction or stroke. The two newer HF definitions will be compared with the traditional one in terms of time to major endpoint analysis. DISCUSSION: This trial will differ from others by: (1) detailed repeated hemodynamic assessment including arteriovenous access flow and (2) by careful assessment of adequate hydration to avoid confusion between HF and water overload.