Search

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., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hartinger, Kratky, Hruskova, Slanar and Tesar.)

Despite major advances in the management of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) achieved in the last decades, a large proportion of AAV patients still develop end-stage renal disease. The survival of AAV patients dependent on dialysis is significantly worse compared with dialysis-independent AAV patients, but is comparable to other non-diabetic patients requiring dialysis. Renal transplantation (RTx) is the method of choice among renal replacement therapies and there has been increasing evidence that it is a suitable method with favorable patient- and graft-survival also in AAV patients. It is recommended to perform RTx after ≥12 months of remission, and ANCA positivity at the time of RTx is generally not considered a contraindication. Even though the risk of relapse after RTx is relatively low with current post-transplant immunosuppressive regimens, disease recurrence may occur. Besides cyclophosphamide, rituximab might become a therapeutic alternative for post-transplant AAV recurrence in the near future but its efficacy and safety in this setting needs to be confirmed in larger studies., (© The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Background: Histopathological lesions in renal biopsy (RB) at presentation of ANCA-associated vasculitis (AAV) have been described in depth but repeat protocolized renal biopsies are seldomly performed in AAV. In this study, we present a group of AAV patients with repeat protocolized biopsies, and we evaluate their clinical significance., Methods: A total of 17 consecutive patients diagnosed between 1991 and 1995 with AAV and renal involvement confirmed by biopsy at presentation in a single center underwent a protocol planned rebiopsy in remission after a median of 13 months (range 11-28) from diagnosis. Biopsies were assessed by two independent pathologists, blinded to patient data. Clinical data were collected retrospectively., Results: Patients were followed-up for a median of 189 months from diagnosis. Renal relapse was observed in eight patients (47.1%), seven patients died, three patients reached end-stage renal failure. There was a significant decrease in the percentage of acute lesions (cellular crescents, fibrinoid necrosis, P < 0.001) and a significant increase in chronic lesions (glomerulosclerosis, interstitial fibrosis, P ≤ 0.01) in the repeat RB compared with the first RB. This resulted in a class change over the biopsies within most patients. The percentage of normal glomeruli in the first biopsy positively correlated with estimated GFR at the end of follow-up (rs = 0.509, P = 0.05)., Conclusions: This is the first study on protocolized repeat biopsies in AAV, giving insight into disease activity under immunosuppressive treatment. Apparently, many AAV patients have grumbling disease with ongoing activity, eventually leading to an increased amount of chronic lesions., (© The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

ANCA-associated vasculitis (AAV) is a potentially life-threatening disease with frequent and often severe kidney involvement which may result in end-stage renal disease. Anti-PR3 and anti-MPO disease are genetically distinct diseases and may have a different pathogenesis. Recent discovery of new autoantibodies (anti-LAMP-2) and the role of complement activation in the pathogenesis of AAV could result in better monitoring of the activity of the disease and identification of new treatment targets. The outcome of patients with AAV has dramatically improved, but long-term mortality still remains relatively high partly due to effective but relatively toxic immunosuppressive treatment. Recent studies demonstrated that B-cell depletion with rituximab is comparable to cyclophosphamide as induction treatment in newly diagnosed AAV patients and better than cyclophosphamide in relapsing patients. Rituximab-based maintenance treatment is superior to standard treatment with azathioprine. The use of more targeted treatment will hopefully be translated into a better long-term outcome of AAV patients., (Copyright © 2013 S. Karger AG, Basel.)

The natural course of as-yet-untreated ANCA-associated vasculitis (AAV) or complications of immunosuppressive treatment may result in rapid clinical deterioration with the need of admission to an intensive care unit (ICU). The aim of this retrospective study was to assess the outcome of patients with renal AAV admitted to the ICU in a single center. We reviewed the medical records of all 218 patients with AAV followed in our department between January 2001 and December 2006 and selected those admitted to the ICU. To assess the severity of critical illness, the Acute Physiology and Chronic Health Evaluation (APACHE II) and Sequential Organ Failure Assessment (SOFA) score on the first ICU day were calculated. Birmingham Vasculitis Activity Score (BVAS) was calculated to represent the total disease activity. Thirty patients with AAV (11 women, 19 men; mean age 61.5 +/- 13.2 years; 20 x cANCA, 10 x pANCA positive) were included. The most common reasons for ICU admission were as follows: active vasculitis (13 patients, 43.3 %), infections (7 patients, 23.3%), and other causes (10 patients, 33.3%). The in-ICU mortality was 33.3% (10 patients). The most common cause of death was septic shock (in 5 patients). The APACHE II (33.5 vs. 23.8) and SOFA scores (11.9 vs. 6.6), but not BVAS (11.5 vs. 16.1), were statistically significantly higher in non-survivors than in survivors (p < 0.01). In conclusion, the in-ICU mortality in AAV patients may be predicted by APACHE II and SOFA scores. While active vasculitis is the most frequent reason for ICU admission, the mortality rate is highest in patients with infectious complications.

The discovery of anti-podocyte antibodies in primary membranous nephropathy (MN) has revolutionized our approach toward the diagnosis and treatment of this disease. Evaluation of serum levels of anti-podocyte antibodies paved the way for non-invasive diagnosis and helped distinguish between primary and secondary MN although the relationship between anti-podocyte antibodies and cancer remains to be elucidated. Serum levels of anti-PLA2R antibodies directed against the major podocyte autoantigen are related to MN activity and the decrease in serum levels of anti-PLA2R antibodies in response to treatment (immunologic remission) also serves as an early indicator of the later putative proteinuric remission, enabling personalization of the treatment. The serum levels of anti-podocyte antibodies also enable the prediction of renal outcomes in terms of both remission and the risk of progression to end-stage renal disease. The positivity of anti-PLA2R antibodies before renal transplantation is associated with the risk of recurrence of MN. It remains to be established if all these relations observed in patients with anti-PLA2R antibodies are also valid for expanding spectrum of antibodies directed against recently discovered minor antigens (e.g., THSD7A, NELL-1, semaphorin 3B). [ABSTRACT FROM AUTHOR]

Objective: End points currently used in lupus nephritis (LN) clinical trials lack uniformity and questionably reflect long‐term kidney survival. This study was undertaken to identify short‐term end points that predict long‐term kidney outcomes for use in clinical trials. Methods: A database of 944 patients with LN was assembled from 3 clinical trials and 12 longitudinal cohorts. Variables from the first 12 months of treatment after diagnosis of active LN (prediction period) were assessed as potential predictors of long‐term outcomes in a 36‐month follow‐up period. The long‐term outcomes examined were new or progressive chronic kidney disease (CKD), severe kidney injury (SKI), and the need for permanent renal replacement therapy (RRT). To predict the risk for each outcome, hazard index tools (HITs) were derived using multivariable analysis with Cox proportional hazards regression. Results: Among 550 eligible subjects, 54 CKD, 55 SKI, and 22 RRT events occurred. Variables in the final CKD HIT were prediction‐period CKD status, 12‐month proteinuria, and 12‐month serum creatinine level. The SKI HIT variables included prediction‐period CKD status, International Society of Nephrology (ISN)/Renal Pathology Society (RPS) class, 12‐month proteinuria, 12‐month serum creatinine level, race, and an interaction between ISN/RPS class and 12‐month proteinuria. The RRT HIT included age at diagnosis, 12‐month proteinuria, and 12‐month serum creatinine level. Each HIT validated well internally (c‐indices 0.84–0.92) and in an independent LN cohort (c‐indices 0.89–0.92). Conclusion: HITs, derived from short‐term kidney responses to treatment, correlate with long‐term kidney outcomes, and now must be validated as surrogate end points for LN clinical trials. [ABSTRACT FROM AUTHOR]

Background: The prognostic value of the anti-neutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis (GN) classification has been demonstrated in several cohorts with sclerotic class having the worst renal outcome. Relevant published data on factors predicting outcomes in sclerotic ANCA GN is limited.Methods: Sclerotic ANCA GN patients were recruited from 5 centers worldwide for this retrospective cohort study. We describe the clinical characteristics of this cohort and evaluate predictors of 1-year glomerular filtration rate (GFR) and end-stage renal disease (ESRD). Kidney function at 12 months as measured by Modification of Diet in Renal Disease estimated GFR (eGFR) was modeled by simple and multiple linear regression analyses. We used Cox proportional hazards regression modeling to evaluate ESRD-free survival.Results: Of the 50 patients, 92% were Caucasian and 60% male with a mean age of 61 years. While 72% had renal limited disease, 82% were MPO ANCA positive. Kidney biopsies contained a median of 20 (interquartile range [IQR] 15-34) glomeruli with 96% showing moderate to severe interstitial fibrosis. Overall, 96% of patients received immunosuppressive drug therapy and 16% received plasmapheresis. Treatment response was achieved in all but 1 patient. The median (IQR) eGFR at entry was 14.5 (9-19) mL/min/1.73 m2. Over a median (IQR) follow-up of 33.5 (17-82) months, 26 patients reached ESRD. Ten patients died with 6 of the deaths occurring within the first year of diagnosis. The hazard of progression to ESRD was significantly higher in those with lower GFR at study entry (p = 0.003) and with higher degree of tubular atrophy (p = 0.043).Conclusions: Renal recovery is rare among sclerotic ANCA GN patients requiring dialysis at entry and 12% of patients died in the first year. Entry GFR and tubular atrophy were significant predictors of GFR at 12 months and renal survival in patients with sclerotic class ANCA GN. [ABSTRACT FROM AUTHOR]

Background: Rapidly progressive glomerulonephritis (RPGN) is characterized by a rapid deterioration of renal function and by extracapillary proliferation in >50% of glomeruli. The most common type of RPGN is “pauci-immune” glomerulonephritis caused by anti-neutrophil cytoplasmic antibodies-associated vasculitis (AAV). Summary: The incidence of AAV increases with age and pauci-immune glomerulonephritis is the most common diagnosis found in renal biopsies in the elderly population. Age was identified as an independent negative risk factor for both death and end-stage renal disease in AAV, and the mortality of older patients was uniformly higher than in younger patients in all retrospective studies. Early diagnosis may be difficult particularly in elderly patients with renal-limited disease but is important for the good outcome of the patients. Immunosuppressive treatment options include cyclophosphamide or rituximab combined with corticosteroids with or without plasma exchange in case of severe disease. Data from randomized trials are completely missing for patient aged >75 years. Based on retrospective studies, elderly patients seem to respond to immunosuppressive drugs just as younger patients are able to, but they are at a higher risk of adverse events. Key Messages: RPGN is relatively common in the elderly patients. Immunosuppressive treatment in older patients with AAV or RPGN may be useful but needs to be strictly individualized with all the risks taken into consideration. Further studies are needed to examine the role of novel therapeutic options in the elderly population with RPGN. [ABSTRACT FROM AUTHOR]