Chances of Renal Recovery for Dialysis-Dependent ANCA-Associated Glomerulonephritis

Urine epidermal growth factor as a biomarker for kidney function recovery and prognosis in glomerulonephritis with severe kidney function impairment

BACKGROUND

Prognostication in glomerulonephritis with severe kidney function impairment is critical for evaluating the benefit-to-risk ratio of immunosuppression. We hypothesized that the urine biomarker epidermal growth factor (EGF) could have good discrimination power to identify subjects who might ultimately recover kidney function.

METHODS

We included 82 subjects with glomerulonephritis and severe kidney function impairment at admission (estimated glomerular filtration rate [eGFR] ≤ 30 mL/min/1.73m2): 58 with lupus nephritis (LN) and 24 with ANCA-associated vasculitis (AAV). Thirty-five subjects required kidney replacement therapy (KRT) at presentation. Urine epidermal growth factor was measured and corrected by urine creatinine (uEGF/Cr) and the population was analyzed by uEGF/Cr tertiles. The primary outcome was time to recovery of eGFR ≥ 30 mL/min/1.73m2 and time to recovery of kidney function with dialysis independence in those with initial KRT.

RESULTS

Forty-four (54%) participants met the primary outcome of recovery of eGFR ≥ 30 mL/min/1.73m2. The 6-month recovery rates were 93%, 57%, and 0% for participants in the highest, middle, and lowest uEGF/Cr tertile, respectively. Recovery of the kidney function was faster and led to a higher post-therapy eGFR in the highest uEGF/Cr tertile. In the ROC analysis, uEGF/Cr was a predictor of recovery with an area under the curve (AUC) of 0.92 (95% CI 0.87-0.98), and a cutoff of 2.60 ng/mg had 100% sensitivity to detect patients who recovered kidney function. In the subgroup of participants with initial KRT, the cut-off of uEGF/Cr of 2.0 ng/mg had 100% sensitivity to detect participants who recovered kidney function with dialysis independence by 6 months.

CONCLUSIONS

Urine EGF/Cr is a promising biomarker to aid in the prediction of recovery of kidney function in glomerulonephritis with severe kidney function impairment.

Kidney Failure in Pauci-immune Crescentic Glomerulonephritis: Rationale for Immunosuppression to Improve Kidney Outcome

PURPOSE OF REVIEW

Pauci-immune crescentic glomerulonephritis is the hallmark finding in ANCA-associated vasculitis (AAV) when the kidneys are affected. The rationale for immunosuppression in AAV is based on the underlying autoimmune nature of the disease. Overall remission rates, kidney outcomes, and the burden of disease have greatly improved since the discovery of various immunosuppressive therapies, but relapses remain common, and a significant proportion of patients continue to progress to end-stage kidney disease. Here, we review the role of immunosuppressive therapies for the treatment of pauci-immune crescentic glomerulonephritis.

RECENT FINDINGS

Besides the recognized role of B and T cells in the pathogenies of AAV, the focus on the contribution of inflammatory cytokines, neutrophil extracellular traps (NETs), and the complement system allowed the discovery of new therapies. Specifically, the C5a receptor blocker (avacopan) has been approved as a glucocorticoid-sparing agent. Additionally, based on observational data, more clinicians are now using combination therapies during the induction phase. There is also an evolving understanding of the role of plasma exchange in removing ANCA antibodies. Furthermore, the recent development of risk score systems provides physicians with valuable prognostic information that can influence decisions on immunosuppression, although future validation from larger cohorts is needed. The over-activation of various immune pathways plays a significant role in the pathogenesis of pauci-immune crescentic glomerulonephritis in AAV. Immunosuppression is, therefore, an important strategy to halt disease progression and improve overall outcomes. Relapse prevention while minimizing adverse events of immunosuppression is a major long-term goal in AAV management.

Plasma exchange in patients with ANCA-associated vasculitis

ANCA-associated Vasculitides (AAV) are characterized by small vessel necrotizing inflammation and can present with multisystem organ involvement, including organ/life threatening manifestations of rapidly progressive glomerulonephritis and diffuse alveolar haemorrhage, where immediate and aggressive intervention is needed to prevent further organ damage. Although, the rationale of plasma exchange (PLEX) in AAV is strong, through removing the pathogenic ANCAs; target either myeloperoxidase (MPO) or proteinase 3 (PR3), and other inflammatory molecules, especially in the initiation when the immunosuppressive treatment is no sufficient to prevent the organ damage, overall impact on patient outcomes is not well-established, while the risk of infections seems to be higher in the PLEX-treated patients. A comprehensive overview of the challenges and uncertainties surrounding the use of PLEX in the management of AAV will be reviewed, providing the current practice recommendations guiding treatment decisions.

Recovery and long-term renal outcome of patients with anti-neutrophil cytoplasmic antibody-associated vasculitis who are on dialysis at presentation

Objective

Renal involvement in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) can lead to severe renal dysfunction requiring dialysis at diagnosis. We aimed to study the clinical and pathologic characteristics of patients with AAV dependent on dialysis at presentation and the long-term renal outcomes of patients who recovered from dialysis.

Methods

This retrospective study analyzed data of patients diagnosed with AAV who were on dialysis from July 2005 to May 2021 at a single tertiary center in Korea.

Results

Thirty-four patients were included in the study (median age 64.5 years, females 61.8%), of which 13 discontinued and 21 continued dialysis. The proportion of normal glomeruli (p<0.001) and interstitial fibrosis (p=0.024) showed significant differences between both groups. Multivariable analysis showed that the proportion of normal glomeruli was associated with dialysis discontinuation (odds ratio=1.29, 95% confidence interval 0.99~1.68, p=0.063), although without statistical significance. Treatment modalities, including plasmapheresis, did not show significance with dialysis discontinuation. In the follow-up analysis of 13 patients who had discontinued dialysis for a median of 81 months, 12 did not require dialysis, and their glomerular filtration rate values significantly increased at follow-up time compared to when they stopped dialysis (37.5 [28.5~45.5] vs. 24.0 [18.5~30.0] mL/min/1.73 m²; p=0.008).

Conclusion

Approximately 38% of AAV patients on dialysis discontinued dialysis, and the recovered patients had improved renal function without dialysis during longer follow-up. Patients with AAV on dialysis should be given the possibility of dialysis discontinuation and renal recovery, especially those with normal glomeruli in kidney pathology.

Prognostic value of proteinuria monitoring in anti-neutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

To determine the prognostic significance of proteinuria monitoring in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV).

METHODS

We retrospectively analyzed the data of kidney biopsy-confirmed patients with AAV. Proteinuria was evaluated by a urine dipstick test. Poor renal outcome was defined as stage 4/5 chronic kidney disease (CKD) (estimated glomerular filtration rate < 30 mL/min/1.73 m2).

RESULTS

We enrolled 77 patients with a median follow-up duration of 36 months (interquartile range, 18-79) in this study. Excluding 8 patients on dialysis at 6 months, 59/69 (85.5%) achieved remission after induction therapy. Patients were then divided into two groups according to the presence of proteinuria at 6 months after induction therapy (n = 29 with proteinuria, 40 without proteinuria). There was no significant difference in the rate of relapse or death according to the presence of proteinuria (p = 0.304 relapse, 0.401 death). In contrast, patients with proteinuria had significantly lower kidney function than those without proteinuria (41 vs. 53.5 mL/min/1.73 m2, p = 0.003). Multivariate analysis revealed that eGFR values at 6 months (hazard ratio [HR] 0.925; 95% CI 0.875-0.978, p = 0.006) and proteinuria at 6 months (HR 4.613; 95% CI 1.230-17.298, p = 0.023) were significantly associated with stage 4/5 CKD.

CONCLUSION

The presence of proteinuria at 6 months after induction therapy and low renal function was significantly associated with a higher risk of stage 4/5 CKD in patients with AAV. Monitoring for proteinuria after induction therapy may help predict poor renal outcomes in patients with AAV.

Management of antineutrophil cytoplasmic antibody-associated vasculitis: a changing tide

PURPOSE OF REVIEW

Antineutrophil cytoplasmic antibody associated vasculitis (AAV) is a group of autoimmune disorders of small blood vessels. While outcomes in AAV have improved with the use of glucocorticoids (GC) and other immunosuppressants, these treatments are associated with significant toxicities. Infections are the major cause of mortality within the first year of treatment. There is a move towards newer treatments with better safety profiles. This review reflects on recent advances in the treatment of AAV.

RECENT FINDINGS

The role of plasma exchange (PLEX) in AAV with kidney involvement has been clarified with new BMJ guideline recommendations following the publication of PEXIVAS and an updated meta-analysis. Lower dose GC regimens are now standard of care. Avacopan (C5a receptor antagonist) was noninferior to a regimen of GC therapy and is a potential steroid-sparing agent. Lastly, rituximab-based regimens were noninferior to cyclophosphamide in two trials for induction of remission and superior to azathioprine in one trial of maintenance of remission.

SUMMARY

AAV treatments have changed tremendously over the past decade with a drive towards targeted PLEX use, increased rituximab use and lower GC dosing. Striking a crucial balance between morbidity from relapses and toxicities from immunosuppression remains a challenging path to navigate.

Sustained Recovery of Kidney Function in Patients with ESKD under Chronic Dialysis Treatment: Systematic Review and Meta-Analysis

The prevalence of recovery of kidney function (RKF) in patients under maintenance dialysis is poorly defined mainly because of different definitions of RKF. Therefore, to gain more insights into the epidemiology of RKF, we performed a systematic review and meta-analysis of studies addressing the prevalence of sustained (at least for 30 days) RKF in patients under maintenance dialysis. Acute kidney injury (AKI) and RKF in the first 90 days of dialysis were the main exclusion criteria. Overall, 7 studies (10 cohorts) including 2,444,943 chronic dialysis patients (range: 430-1,900,595 patients) were meta-analyzed. The period of observation ranged from 4 to 43 years. The prevalence of RKF was 1.49% (95% C.I.:1.05-2.11; p < 0.001] with high heterogeneity I2: 99.8%, p < 0.001. The weighted mean dialysis vintage before RKF was 294 ± 165 days; RKF persisted for a weighted mean of 27.5 months. The percentage of RKF was higher in studies from the U.S. (1.96% [95% C.I.: 1.24-3.07]) as compared to other countries (1.04% [95%C.I.: 0.66-1.62]; p = 0.049). In conclusion, sustained RKF unrelated to AKI occurs in about 1.5% of patients under maintenance dialysis. On average, RKF patients discontinue chronic dialysis about ten months after starting treatment and live free of dialysis for more than two years. The higher prevalence of RKF reported in the U.S. versus other countries suggests a major role of country-specific policies for dialysis start.

PLEX in AAV-GN: insights from the meta-analysis results and impact on remission induction treatment recommendations

The risk of progression to end-stage kidney disease (ESKD) in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and glomerulonephritis (AAV-GN) remains high. At 5 years of follow-up, 14-25% of patients will evolve to ESKD, suggesting that kidney survival is not optimized in patients with AAV. The addition of plasma exchange (PLEX) to standard remission induction has been the standard of care, particularly in patients with severe renal disease. However, there is still some debate regarding which patients benefit from PLEX. A recently published meta-analysis concluded that the addition of PLEX to standard remission induction in AAV probably reduced the risk of ESKD at 12 months and that PLEX was associated with an estimated absolute risk reduction for ESKD at 12 months of 16.0% for those at high risk or with a serum creatinine >5.7 mg/dl (high certainty of important effects). These findings were interpreted as supportive of offering PLEX to patients with AAV and a high risk of progression to ESKD or requiring dialysis and are making their way into societies recommendations. However, the results of the analysis can be debated. We provide an overview on the meta-analysis as an attempt to guide the audience through how the data were generated, to comment on our interpretation of the results and to explain why we feel uncertainty remains. In addition, we would like to provide insights in two questions that we believe are very relevant to consider when addressing the role of PLEX: the role of kidney biopsy findings in the decision making of whom might benefit from PLEX and the impact of novel treatments (i.e. complement factor 5a inhibitors) in avoiding progression to ESKD at 12 months. The treatment of patients with severe AAV-GN is complex and further studies that include only patients at high risk of progression to ESKD are needed.

Histopathological prognostic factors in ANCA-associated glomerulonephritis

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are a group of multisystemic autoimmune diseases characterized by necrotizing inflammation of small vessels. Kidney involvement is frequent in granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA), and accounts for a significant proportion of the morbidity and mortality related to these diseases. Despite improvement in therapeutic management of ANCA-glomerulonephritis (ANCA-GN), end-stage kidney disease (ESKD) still occurs in up to 30% of affected patients within 5 years following diagnosis. Thus, identifying patients for whom aggressive immunosuppressive therapy will be more beneficial than deleterious is of great importance. Several clinical, biological and histological factors have been proposed as predictors of ESKD. The kidney biopsy is essential not only for the diagnosis, but also for evaluating renal prognosis. In this review, we discuss the prognostic value of renal lesions at the diagnosis of ANCA-GN by analyzing each compartment of the nephron. We also review existing ESKD risk classification in ANCA-GN and finally propose an example of a standardized pathology report that could be used in routine practice.

MPO-ANCA-Positive Granulomatosis with Polyangiitis with Rapidly Progressive Glomerulonephritis and Saddle-Nose Deformity: A Case Report

Early diagnosis and initiation of appropriate immunosuppressive treatment remain the cornerstone of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis at the cost of significant toxicity. In this report, we present a case of a 69-year-old female who presented with advanced renal insufficiency and evidence of pulmonary hemorrhage and was MPO-ANCA-positive with a clinical phenotype of granulomatosis with polyangiitis. Organ involvement included rapidly progressive glomerulonephritis (GN), along with extrarenal manifestations (skin, upper and lower respiratory system involvement, and onset of saddle-nose deformity). Kidney biopsy established the diagnosis of pauci-immune crescentic, sclerotic GN. She received therapy with glucocorticoids and cyclophosphamide, mainly due to life-threatening extra-renal manifestations, such as pulmonary hemorrhage. She avoided vasculitis-related death but she developed severe therapy-related toxicity, resulting in the discontinuation of immunosuppressive therapy. Continuous re-evaluation of patients with ANCA-associated vasculitis in terms of response to immunosuppressive therapy and treatment-related toxicity is crucial for their management.

Consideration of Therapeutic Plasma Exchange in Association With Inflammatory Lesions in ANCA-Associated Glomerulonephritis: A Real-World Retrospective Study From a Single Center

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic vasculitis, most frequently presenting as microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA). Pathogenic ANCAs trigger a deleterious immune response resulting in pauci-immune necrotizing and crescentic glomerulonephritis (GN). Standard therapeutical regimens include aggressive immunosuppressive therapy. Since some patients require renal replacement therapy (RRT) despite intensive immunosuppressive therapy, additional therapeutic plasma exchange (PEX) to deplete pathogenic ANCAs has been recommended but its value has recently been questioned. Because therapeutic decision making is crucial in these critically ill patients, we here aimed to identify inflammatory lesions in association with PEX consideration in a retrospective study from a single center tertiary hospital in a real-world population of 46 patients with severe AAV requiring intensive care treatment. The decision to consider PEX was more likely in patients with need for intensive care treatment and severe renal dysfunction. In contrast, short-term outcomes did not depend on clinical, or laboratory characteristics assessed at admission. Histopathological analysis confirmed active disease reflected by increased glomerular necrosis and crescents, but these histopathological findings did not associate with short-term outcome either. Interestingly, only increased global glomerular sclerosis in renal biopsies associated with a detrimental short-term outcome. In conclusion, our study investigated determinants for the consideration of therapeutic PEX in patients with severe AAV requiring intensive care treatment. This aspect underscores the need for renal biopsy and requires further investigation in a prospective controlled setting for therapeutic decision making especially in patients with severe AAV requiring intensive care treatment, especially important for treating intensivists.

Recovery of kidney function in patients treated with maintenance dialysis-a report from the ERA-EDTA Registry

BACKGROUND

Literature on recovery of kidney function (RKF) in patients with end-stage kidney disease treated with maintenance dialysis (i.e. >90 days) is limited. We assessed the incidence of RKF and its associated characteristics in a European cohort of dialysis patients.

METHODS

We included adult patients from the European Renal Association-European Dialysis and Transplant Association Registry who started maintenance dialysis in 1997-2016. Sustained RKF was defined as permanent discontinuation of dialysis. Temporary discontinuation of ≥30 days (non-sustained RKF) was also evaluated. Factors associated with RKF adjusted for potential confounders were studied using Cox regression analyses.

RESULTS

RKF occurred in 7657 (1.8%) of 440 996 patients, of whom 71% experienced sustained RKF. Approximately 90% of all recoveries occurred within the first 2 years after Day 91 of dialysis. Of patients with non-sustained RKF, 39% restarted kidney replacement therapy within 1 year. Sustained RKF was strongly associated with the following underlying kidney diseases (as registered by the treating physician): tubular necrosis (irreversible) or cortical necrosis {adjusted hazard ratio [aHR] 20.4 [95% confidence interval (CI) 17.9-23.1]}, systemic sclerosis [aHR 18.5 (95% CI 13.8-24.7)] and haemolytic uremic syndrome [aHR 17.3 (95% CI 13.9-21.6)]. Weaker associations were found for haemodialysis as a first dialysis modality [aHR 1.5 (95% CI 1.4-1.6)] and dialysis initiation at an older age [aHR 1.8 (95% CI 1.6-2.0)] or in a more recent time period [aHR 2.4 (95% CI 2.1-2.7)].

CONCLUSIONS

Definitive discontinuation of maintenance dialysis is a rare and not necessarily an early event. Certain clinical characteristics, but mostly the type of underlying kidney disease, are associated with a higher likelihood of RKF.

Is There a Role for Plasma Exchange in ANCA-Associated Vasculitis?

Purpose of review

This review summarises the evidence for the use of therapeutic plasma exchange (TPE) in anti-neutrophil cytoplasm antibody (ANCA)–associated vasculitis. TPE is an extra-corporeal treatment which efficiently removes IgG and other pathogenic small molecules from the blood. There are several mechanistic reasons why this should be of benefit in AAV including the well-described pathogenicity of ANCA.

Recent findings

The recently published PEXIVAS trial is the largest study of TPE in AAV to date. It did not show a benefit for adjunctive TPE on a primary end point of ESRD or death. There was no difference in serious adverse events between those treated with TPE and those treated with immunosuppressive drugs alone.

Conclusions

Based on the results of PEXIVAS, most patients with AAV should not be treated with adjunctive TPE. However, there are subgroups of patients with AAV for whom TPE may still be of benefit, including those with double positivity for anti-GBM antibodies and ANCA.

Urinary angiotensinogen: an indicator of active antineutrophil cytoplasmic antibody-associated glomerulonephritis

BACKGROUND

One of the major challenges in improving the management of antineutrophil cytoplasmic antibody-associated glomerulonephritis (ANCA-GN) is the lack of a disease-specific indicator for histological lesions and disease activity. Here we tested the utility of urinary angiotensinogen (UAGT) as a biomarker of renal disease activity in ANCA-GN.

METHODS

A prospective, two-stage cohort study was performed in ANCA-GN patients. In Stage I, UAGT was measured at the time of renal biopsy in 69 patients from two centers (test set) and 25 patients from two other centers (validation set). In Stage II, UAGT was monitored in 50 subjects in the test set for 24 months.

RESULTS

In Stage I, UAGT significantly increased in ANCA-GN patients, correlating well with cellular crescents formation and active interstitial inflammation. Patients with crescentic ANCA-GN exhibited the highest UAGT compared with other histopathological classes of ANCA-GN. After multivariable adjustment, the highest quartile of UAGT, compared with the lowest quartile, associated with a 6-fold increased risk of crescentic ANCA-GN. For predicting crescentic ANCA-GN, UAGT [area under the receiver operating characteristics curve (AUC) = 0.88] outperformed albuminuria (AUC = 0.73) and estimated glomerular filtration rate (AUC = 0.69). UAGT improved the performance of those clinical markers in diagnosing crescentic ANCA-GN (P < 0.034), suggesting a role of UAGT in identifying active crescentic ANCA-GN. In Stage II, UAGT decreased after immunotherapy and increased at the time of renal relapse during the 2-year follow-up, suggesting the usefulness of UAGT to monitor disease activity over time.

CONCLUSIONS

These results suggest the potential use of UAGT for assessing disease activity and renal relapse in ANCA-GN.

Treatment and its side effects in ANCA-associated vasculitides - Study based on POLVAS registry data

PURPOSE

The aim of this study is to present the treatment modalities and associated side effects in a Polish nation-wide ANCA-associated vasculitides (AAV) patients' cohort.

MATERIALS AND METHODS

Retrospective analysis of patients diagnosed with AAV between 1990 and 2016, included in the POLVAS registry was performed. Standard descriptive statistic methods were used with an emphasis on the treatment modalities.

RESULTS

There were 625 patients diagnosed with AAV included in this study: 417 cases of granulomatosis with polyangiitis (GPA; 66.7%), 106 cases of microscopic polyangiitis (MPA; 17.0%) and 102 cases of eosinophilic granulomatosis with polyangiitis (EGPA; 16.3%). The mean age at the date of diagnosis was 50.4 (±15.7) years and the median observational period amounted to 4.0 (2.0-8.0) years. Glucocorticosteroids (GCs) were the medicaments most frequently used for remission induction (593/622; 95.3%), followed by cyclophosphamide (487/622; 78.3%), rituximab (44/622; 7.1%), and methotrexate (39/622; 6.3%). GCs were also most frequently administered for maintenance therapy (499/592; 84.3%), followed by azathioprine (224/592; 37.8%), methotrexate (136/592; 23.0%) and mycophenolate mofetil (99/592; 16.7%). The median cumulative doses of cyclophosphamide and rituximab equalled 7.99 g (4.18-14.0) and 2000 mg (1500-2800), respectively. The most commonly observed adverse events included: infections - 214/551 cases (38.8%), which were associated with the time of observation (OR = 1.05; 95% CI 1.01-1.10), the use of GCs intravenous pulses (OR = 2.76; 95% CI 1.68-4.54) and need for haemodialysis (OR = 1.73; 95% CI 1.10-2.71).

CONCLUSIONS

Polish patients with AAV were predominantly treated according to appropriate guidelines. The most frequent adverse events were typical for usually administered immunosuppressive treatment.

Validation of a renal risk score in a cohort of ANCA-associated vasculitis patients with severe kidney damage

OBJECTIVE

To validate the renal risk score in a cohort of patients with advanced kidney damage.

METHODS

A total of 72 patients with biopsy-proven ANCA glomerulonephritis with >12 months of follow-up were studied. The renal risk score was calculated and evaluated by survival analysis for time of renal survival. Cohort-specific clinical, histopathologic, and post-treatment factors associated with renal survival were determined by Cox regression analysis.

RESULTS

Kidney biopsies were classified as focal, crescentic, mixed, and sclerotic classes in 6 (8%), 4 (6%), 25 (35%), and 37 (51%) patients, respectively. The 1-, 3-, and 5-year renal survival rates were 79%, 73%, and 68%, respectively. Patients were segregated by the risk score in low- (18%), medium- (47%), and high-risk (35%) groups. Patients in the low-risk group had 36-, 60-, and 84-month renal survival of 100%; those in the medium risk 85% (95% CI 72-92), 81% (95% CI 66-95), and 76% (95% CI 60-92), respectively; and those in the high risk 37% (95% CI 17-57), 26% (95% CI 7-45), and 18% (95% CI 1-36), respectively. Six (43%) of the 14 patients in the high-risk group recovered renal function after the initial episode, and 2 (14%) remained dialysis-free. Other parameters associated with renal survival included age, proteinuria, general symptoms, cellular crescents, glomerulosclerosis, tubulointerstitial lesions, best post-treatment eGFR, and renal relapses.

CONCLUSIONS

We validated the renal risk score as a prognostic tool in a cohort with predominantly mixed and sclerotic histologic categories. Since patients in the high-risk group still benefited from immunosuppressive therapy, this score should be used in conjunction with other predictive parameters to aid therapeutic decisions.Key Points• The ANCA renal risk score is validated in a cohort with advanced kidney damage.• Patients in the high-risk group still benefited from immunosuppressive therapy.• Parameters not included in the risk score are associated with renal survival and may be useful.

Interventions for renal vasculitis in adults

BACKGROUND

Renal vasculitis presents as rapidly progressive glomerulonephritis and comprises of a group of conditions characterised by acute kidney injury (AKI), haematuria and proteinuria. Treatment of these conditions involve the use of steroid and non-steroid agents in combination with plasma exchange. Although immunosuppression overall has been very successful in treatment of these conditions, many questions remain unanswered in terms of dose and duration of therapy, the use of plasma exchange and the role of new therapies. This 2019 publication is an update of a review first published in 2008 and updated in 2015.

OBJECTIVES

To evaluate the benefits and harms of any intervention used for the treatment of renal vasculitis in adults.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 21 November 2019 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials investigating any intervention for the treatment of renal vasculitis in adults.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. Statistical analyses were performed using a random effects model and results expressed as risk ratio (RR) with 95% confidence intervals (CI) for dichotomous outcomes or mean difference (MD) for continuous outcomes.

MAIN RESULTS

Forty studies (3764 patients) were included. Studies conducted earlier tended to have a higher risk of bias due to poor (or poorly reported) study design, broad inclusion criteria, less well developed disease definitions and low patient numbers. Later studies tend to have improved in all areas of quality, aided by the development of large international study groups. Induction therapy: Plasma exchange as adjunctive therapy may reduce the need for dialysis at three (2 studies: RR 0.43, 95% CI 0.23 to 0.78; I2 = 0%) and 12 months (6 studies: RR 0.45, 95% CI 0.29 to 0.72; I2 = 0%) (low certainty evidence). Plasma exchange may make little or no difference to death, serum creatinine (SCr), sustained remission or to serious or the total number of adverse events. Plasma exchange may increase the number of serious infections (5 studies: RR 1.26, 95% CI 1.03 to 1.54; I2 = 0%; low certainty evidence). Remission rates for pulse versus continuous cyclophosphamide (CPA) were equivalent but pulse treatment may increase the risk of relapse (4 studies: RR 1.79, 95% CI 1.11 to 2.87; I2 = 0%) (low certainty evidence) compared with continuous cyclophosphamide. Pulse CPA may make little or no difference to death at final follow-up, or SCr at any time point. More patients required dialysis in the pulse CPA group. Leukopenia was less common with pulse treatment; however, nausea was more common. Rituximab compared to CPA probably makes little or no difference to death, remission, relapse, severe adverse events, serious infections, or severe adverse events. Kidney function and dialysis were not reported. A single study reported no difference in the number of deaths, need for dialysis, or adverse events between mycophenolate mofetil (MMF) and CPA. Remission was reported to improve with MMF however more patients relapsed. A lower dose of steroids was probably as effective as high dose and may be safer, causing fewer infections; kidney function and relapse were not reported. There was little of no difference in death or remission between six and 12 pulses of CPA. There is low certainty evidence that there were less relapses with 12 pulses (2 studies: RR 1.57, 95% CI 0.96 to 2.56; I2 = 0%), but more infections (2 studies: RR 0.79, 95% CI 0.36 to 1.72; I2 = 45%). One study reported severe adverse events were less in patients receiving six compared to 12 pulses of CPA. Kidney function and dialysis were not reported. There is limited evidence from single studies about the effectiveness of intravenous immunoglobulin, avacopan, methotrexate, immunoadsorption, lymphocytapheresis, or etanercept. Maintenance therapy: Azathioprine (AZA) has equivalent efficacy as a maintenance agent to CPA with fewer episodes of leucopenia. MMF resulted in a higher relapse rate when tested against azathioprine in remission maintenance. Rituximab is an effective remission induction and maintenance agent. Oral co-trimoxazole did not reduce relapses in granulomatosis with polyangiitis. There were fewer relapses but more serious adverse events with leflunomide compared to methotrexate. There is limited evidence from single studies about the effectiveness of methotrexate versus CPA or AZA, cyclosporin versus CPA, extended versus standard AZA, and belimumab.

AUTHORS' CONCLUSIONS

Plasma exchange was effective in patients with severe AKI secondary to vasculitis. Pulse cyclophosphamide may result in an increased risk of relapse when compared to continuous oral use but a reduced total dose. Whilst CPA is standard induction treatment, rituximab and MMF were also effective. AZA, methotrexate and leflunomide were effective as maintenance therapy. Further studies are required to more clearly delineate the appropriate place of newer agents within an evidence-based therapeutic strategy.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

The effect of pulse methylprednisolone induction therapy in Chinese patients with dialysis-dependent MPO-ANCA associated vasculitis

BACKGROUND

Pulse methylprednisolone (MP) was routinely used before commencing standard immunosuppressive therapy for induction of remission in patients with dialysis-dependent anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in spite of the paucity of evidence of benefit. The aim of this study was thus to determine whether the addition of pulse MP to standard induction immunosuppressive therapy in severe myeloperoxidase (MPO) -AAV patients who were on dialysis at onset is associated with an improvement in kidney recovery and patient survival. Furthermore, we analyzed the factors associated with restoration of kidney function and mortality in a single Chinese cohort.

METHODS

69 MPO-AAV patients who were on dialysis at the time of diagnosis were included in this study. The MP group (n = 30) received pulse MP (5-10 mg/kg/day) for 3 days before the standard immunosuppressive therapy. The Non-MP group (n = 39) had no MP pulses. The outcomes and adverse events between the two groups were compared. In addition, the predictive value of the clinical and histological parameters for kidney and patient survival was assessed using univariate and multivariate logistic regression analysis.

RESULT

There was no difference in patient survival, kidney recovery and the rates of adverse events between the two groups. A higher Birmingham Vasculitis Activity Score (BVAS) was shown to be a negative prognostic factor for kidney function restoration (p = 0.046, OR 0.811, 95% CI 0.660-0.997). BVAS was also demonstrated to be an independent predictor for both all-cause death (p = 0.007, OR 1.324, 95% CI 1.079-1.624) and therapy-related death (p = 0.003, OR 1.574, 95% CI 1.171-2.115). Patients' eGFR at the presentation of the disease was shown to be an independent predictor for therapy-related death (p = 0.027, OR 2.535, 95% CI 1.112-5.779).

CONCLUSIONS

This retrospective study of MPO-AAV patients who required dialysis at presentation in a single Chinese center suggests that the addition of pulse MP to standard immunosuppressive induction therapy for remission appears to confer no benefit in terms of improving patient outcomes. Further research is required to determine the role of pulse MP in severe MPO-AAV.

Plasma Exchange Is Highly Effective for Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis Patients With Rapidly Progressive Glomerulonephritis Who Have Advanced to Dialysis Dependence: A Single-Center Case Series

Plasma exchange (PEX) can be an effective treatment in anti-neutrophil cytoplasmic antibody-associated vasculitis with severe renal damage; however, it is still controversial. Among cases of newly diagnosed AAV with rapidly progressive glomerulonephritis at our department from 2008 onward, 11 patients who received PEX (seven cases for severe renal damage [R-PEX] and four cases for lung hemorrhage [L-PEX]) were retrospectively analyzed. All cases of R-PEX were dependent on hemodialysis at the beginning of PEX and all received seven sessions of PEX (50 mL/kg or 1.3 plasma volume per exchange) within 2 weeks. All cases became dialysis-independent within 8 weeks, with 3- and 12-month cumulative renal survival rates of 100% and 80%, respectively. All cases of L-PEX retained their renal function. In rapidly developing, newly dialysis-dependent antibody-associated vasculitis with rapidly progressive glomerulonephritis patients with normal renal function before disease onset, standard PEX can be expected to induce sufficient renal recovery to establish dialysis independence.

Therapeutic Plasma Exchange in Renal Disorders

Nephrologists use hemodialysis and hemofiltration to remove low molecular weight toxic constituents, and increasingly deploy therapeutic plasma exchange (TPE)/plasmapheresis to eliminate higher molecular weight substances such as immunoglobulins or immune complexes from plasma. This review discusses different modalities of TPE, their application in renal disorders, its rationale and complications. TPE is recommended based on evidence, in alloantibody-mediated diseases such as humoral antibody mediated renal transplant rejection, autoantibody mediated glomerulonephritis (GN) disorders for example, anti-glomerular basement membrane GN, as well as in antineutrophil cytoplasmic antibody mediated GN and antibody mediated thrombotic thrombocytopenic purpura. In many other renal illnesses, the rational use of TPE is gaining currency. Double membrane filtration, immune adsorption and cryofiltration are important modifications in TPE

The treatment of ANCA-associated rapidly-progressive glomerulonephritis and Goodpasture syndrome with therapeutic apheresis

Therapeutic plasma aphresis (plasmapheresis) is one form of treatment that is frequently used in practice of Nephrology. Plasmapheresis is the most important part of the therapies for Goodpasture's syndrome and anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis which are causes of rapidly progressive glomerulonephritis. The reason why the effectiveness of plasmapheresis therapy cannot be clearly demonstrated in renal involvement in these diseases is that it does not appear to be possible to recruit an adequate number of patients and plasmapheresis is not effective in advanced disease if early treatment is not initiated.

Complement in ANCA-associated vasculitis: mechanisms and implications for management

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of potentially life-threatening autoimmune diseases. The main histological feature in the kidneys of patients with AAV is pauci-immune necrotizing crescentic glomerulonephritis with little immunoglobulin and complement deposition in the glomerular capillary walls. The complement system was not, therefore, initially thought to be associated with the development of AAV. Accumulating evidence from animal models and clinical observations indicate, however, that activation of the complement system - and the alternative pathway in particular - is crucial for the development of AAV, and that the complement activation product C5a has a central role. Stimulation of neutrophils with C5a and ANCA not only results in the neutrophil respiratory burst and degranulation, but also activates the coagulation system and generates thrombin, thus bridging the inflammation and coagulation systems. In this Review, we provide an overview of the clinical, in vivo and in vitro evidence for a role of complement activation in the development of AAV and discuss how targeting the complement system could provide opportunities for therapy.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice-Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Seventh Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.

Renal vasculitis presenting with acute kidney injury

Renal failure secondary to ANCA-associated vasculitis represents a clinical and therapeutic challenge. In this study, we aimed to assess the treatment response rates and long-term outcomes of vasculitis patients presenting with renal failure. This retrospective study included 151 patients with renal vasculitis from three hospitals who underwent a renal biopsy between 1997 and 2014. Patients with renal failure which required dialysis at the onset were compared to those presenting with more preserved renal function. The primary end point was treatment response and patient surivival. Patients with severe renal involvement had a lower response to treatment compared to those having preserved renal function (26.6 versus 93.4%; p < 0.001). Dialysis-dependent patients who received plasmapheresis in addition to immune suppressants associated a higher rate of renal recovery (41.6 versus 12.5%; p = 0.05). A higher incidence of severe infections was observed among patients with severe renal involvement (38.4 versus 18.1%, p = 0.01). The mortality rate was significantly higher among vasculitis patients presenting with renal failure (53.8 versus 22.2%, p = 0.001). Global survival at 1 and 5 years was 60 and 47% in patients requiring dialysis compared with 90 and 80% among those with more preserved renal function (p < 0.001). After multivariate adjustment, the need for dialysis remained as an independent predictor of death (HR 2.5; 95% CI 1.1-5.7; p = 0.03). The presence of severe renal dysfunction represents an independent risk factor for patient survival in renal vasculitis. Patients requiring dialysis associate a lower response rate to immunosuppressive therapy and a higher incidence of severe infections.

Predictors of renal histopathology in antineutrophil cytoplasmic antibody associated glomerulonephritis

OBJECTIVES

Prompt, aggressive therapy is vital for anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis. In this regard, we aimed to identify predictors of distinct renal histopathological classes at the time of clinical diagnosis.

PATIENTS & METHODS

An inception cohort of patients with biopsy proven ANCA-associated glomerulonephritis was studied retrospectively. Demographics, clinical, laboratory, serological and radiological parameters were analyzed. Patients were classified on the basis of renal histopathology. A risk score was developed for each histopathological class using univariate and stepwise logistic regression analyses.

RESULTS

Variables independently associated with focal class included disease duration up to diagnosis <8 weeks, absence of erythrocyte casts by urine microscopy and eGFR >49 ml/min/1.73 m(2); with crescentic class >40 erythrocytes/hpf, identification of erythrocyte casts in urine, upper respiratory tract involvement and eGFR <49 ml/min/1.73 m(2); with mixed class age >54 years, male gender, and absence of upper respiratory tract involvement. In the presence of these risk factors a predictive risk score for each histopathological classes was calculated: odds ratio, 95% confidence intervals (CI), for focal class (≥2 risk factors, 20.8 (95% CI: 5.1-84.2), p < 0.0001, and 441.0 (95% CI: 16.8-11,590), p = 0.0003 for crescentic class (≥3 risk factors) while the small number of patients in the mixed and sclerotic class precluded any estimates.

CONCLUSION

We propose a predictive algorithm of specific histolopathological classes of ANCA-associated glomerulonephritis, which might provide a crude estimation of the disease activity in the glomeruli at presentation. This tool might assist the clinician in making decisions regarding the level of intensity of inductive immunosuppressive therapy at clinical diagnosis.

Interventions for renal vasculitis in adults

BACKGROUND

Renal vasculitis presents as rapidly progressive glomerulonephritis which comprises of a group of conditions characterised by acute kidney injury (AKI), haematuria and proteinuria. Treatment of these conditions comprises steroid and non-steroid agents in combination with plasma exchange. Although immunosuppression overall has been very successful in treatment of these conditions, many questions remain unanswered in terms of dose and duration of therapy, the use of plasma exchange and the role of new therapies. This an update of a review first published in 2008.

OBJECTIVES

To evaluate the benefits and harms of any intervention used for the treatment of renal vasculitis in adults.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 27 July 2015 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials investigating any intervention for the treatment of renal vasculitis in adults.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. Statistical analyses were performed using a random effects model and results expressed as risk ratio (RR) with 95% confidence intervals (CI) for dichotomous outcomes or mean difference (MD) for continuous outcomes.

MAIN RESULTS

Thirty one studies (2217 patients) were included. Studies conducted earlier tended to have a higher risk of bias due to poor (or poorly reported) study design, broad inclusion criteria, less well developed disease definitions and low patient numbers. Later studies tend to have improved in all areas of quality, aided by the development of large transnational study groups.Plasma exchange as adjunctive therapy significantly reduces the risk of end-stage kidney disease at three months (2 studies: RR 0.43, 95% CI 0.23 to 0.78) and 12 months (6 studies: RR 0.45, 95% CI 0.29 to 0.72). Four studies (300 patients) compared the use of pulse and continuous administration of cyclophosphamide. Remission rates were equivalent but pulse treatment causes an increased risk of relapse (4 studies: RR 1.79, 95% CI 1.11 to 2.87) compared with continuous cyclophosphamide. Azathioprine has equivalent efficacy as a maintenance agent to cyclophosphamide with fewer episodes of leucopenia. Mycophenolate mofetil may be equivalent to cyclophosphamide as an induction agent but resulted in a higher relapse rate when tested against azathioprine in remission maintenance. Rituximab is an effective remission induction agent. Methotrexate or leflunomide are potential choices in remission maintenance therapy. Oral co-trimoxazole did not reduce relapses significantly in granulomatosis with polyangiitis.

AUTHORS' CONCLUSIONS

Plasma exchange was effective in patients with severe AKI secondary to vasculitis. Pulse cyclophosphamide results in an increased risk of relapse when compared to continuous oral use but a reduced total dose. Whilst cyclophosphamide is standard induction treatment, rituximab and mycophenolate mofetil were also effective. Azathioprine, methotrexate and leflunomide were effective as maintenance therapy. Further studies are required to more clearly delineate the appropriate place of newer agents within an evidence-based therapeutic strategy.

Conventional induction and maintenance treatment of Antineutrophil cytoplasmic antibodies-associated vasculitis - still of value for our patients?

INTRODUCTION

Antineutrophil cytoplasmic antibodies-associated vasculitis (AAV) is a group of autoimmune diseases characterized by the necrotizing inflammation of small vessels and associated with the antineutrophil cytoplasmic antibodies. Treatment of AAV can be divided into the induction phase aimed at achieving remission of the disease and the maintenance phase aimed at prevention of relapses. Long-term outcome of AAV dramatically improved with the introduction of cyclophosphamide. Recent clinical studies resulted in the reduction of the cumulative dose of cyclophosphamide and introduction of new treatment options, namely B-cell-depleting antibody rituximab, into both induction and maintenance treatment. This paper aims to evaluate the current role of the conventional induction and maintenance treatment in view of the gradually increasing use of rituximab.

AREAS COVERED

This paper provides an overview of the main clinical studies in induction and maintenance treatment of adult patients with AAV, treatment of relapses of AAV and shortly comments also on the treatment of refractory AAV, treatment of different subgroups of AAV (based on the age, renal function, clinical presentation and type of autoantibody), long-term outcome of patients with AAV, adverse events of treatment and treatment of end-stage renal disease in AAV.

EXPERT OPINION

Our analysis demonstrates that although the introduction of rituximab modified the approach to both the induction and maintenance treatment of AAV, more conventional induction and maintenance treatment with standard immunosuppressive drugs still retains its importance as we need more data on long-term efficacy and safety of biologic treatment, and also its cost-effectiveness still remains an open issue.

Older patients with ANCA-associated vasculitis and dialysis dependent renal failure: a retrospective study

Background

ANCA-associated vasculitis (AAV) with renal involvement is not uncommon in older individuals. Unfortunately, this can be catastrophic requiring hemodialysis (HD) and may lead to end stage renal disease (ESRD). However, more than 50 % of patients with AAV who require HD initially have renal recovery and discontinue HD. The aim of this study was to describe a retrospective cohort of older patients with AAV and severe renal involvement which required hemodialysis.

Methods

Between 1995 and 2013 a total of 30 patients with histologic evidence of pauci-immune glomerulonephritis who required HD were evaluated at a single university center. The association of demographic and clinical parameters with age was assessed. Older age of disease onset was defined as age ≥60 years. The risk of developing ESRD at 3 months was examined using univariate logistic regression analysis.

Results

Among 30 patients with AAV who required HD, the mean age of disease onset was 59 ± 17 years (range 22-88 years). Twelve patients were in the older age group, and 18 were in the younger group. Three months after diagnosis, 43 % of the cohort had ESRD with a statistically similar proportion of older (n = 9, 50 %) versus younger (n = 4, 33 %) patients (p = 0.367). Most patients (93 %) received immunosuppressive therapy. There was not a statistically significant association between age and ESRD.

Conclusions

These data suggest that age alone does not predict renal recovery among individuals on HD due to AAV. Renal recovery is a realistic expectation and outcome, if patients are treated, even among older patients with AAV who require HD initially.

Twenty-five years of RENHIS: a history of histopathological studies within EUVAS

In the early 1990s, an international working group of experienced renal pathologists, the Renal Histology group, set up a scoring system for biopsies with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis. This scoring system subdivided glomerular, interstitial and vascular lesions and served as a tool for the evaluation of all renal biopsies from studies of the European Vasculitis Study Group (EUVAS). Histopathological studies gave new insights into the prediction of renal outcome in patients with ANCA-associated glomerulonephritis. Percentage of normal glomeruli and a selected number of interstitial parameters were reliable predictors of long-term follow-up glomerular filtration rate in all studies. Out of these results, a histopathological classification distinguishing focal, crescentic, mixed and sclerotic classes of ANCA-associated glomerulonephritis was developed. Until today, 13 studies have validated this classification system. Future studies will try to determine if and how renal histology could be helpful in guiding treatment of ANCA-associated glomerulonephritis.

Plasma exchange in antineutrophil cytoplasm antibody-associated vasculitis

PURPOSE OF REVIEW

This article reviews the use of plasma exchange for the treatment of antineutrophil cytoplasm antibody-associated vasculitis (AAV) with a focus on current controversies and knowledge gaps.

RECENT FINDINGS

Experimental evidence suggesting that antineutrophil cytoplasm antibodies are pathogenic continues to evolve and support the theory that rapid removal of antineutrophil cytoplasm antibody with plasma exchange may be beneficial. Although early, small trials of plasma exchange in rapidly progressive glomerulonephritis and vasculitis suggested that plasma exchange may improve a patient's potential for renal recovery, more recent analyses have called the net benefit of plasma exchange into question. Furthermore, there is uncertainty as to whether plasma exchange is beneficial to patients with particular organ manifestations of their AAV (e.g., lung hemorrhage).

SUMMARY

Whether plasma exchange should be used routinely in antineutrophil cytoplasm antibody-associated vasculitis, in patients with certain manifestations or severity of disease only, or not at all, remains unclear. Given that plasma exchange is expensive and invasive, further research to resolve these uncertainties is required.

Renal transplantation in anti-neutrophil cytoplasmic antibody-associated vasculitis

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.

Predictors of treatment outcomes in ANCA-associated vasculitis with severe kidney failure

BACKGROUND AND OBJECTIVES

In ANCA-associated GN, severe renal dysfunction portends a poor prognosis for renal recovery and patient survival. This study evaluated the prognostic factors affecting renal and patient outcomes in patients presenting with severe kidney failure to guide immunosuppressive therapy.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study retrospectively evaluated clinical and histopathologic characteristics of 155 patients who underwent biopsy between October 1985 and February 2011 (median eGFR at presentation, 7.1 ml/min per 1.73 m(2); 87% required hemodialysis), all treated with immunosuppressive medications. Three outcomes of interest were measured: patient survival, renal survival, and treatment response (defined as dialysis-free survival without active vasculitis by 4 months after biopsy). Competing risk, Cox, and logistic regression analyses were conducted for each outcome measure.

RESULTS

Within 4 months after biopsy, treatment response was attained in 51% of patients, 35% remained on dialysis, and 14% died. In a competing risk analysis, estimated cumulative incidence rates of ESRD and disease-related mortality were 26% and 17% at 1 year and 32% and 28% at 5 years, respectively. Cyclophosphamide therapy and treatment response by 4 months were independently associated with patient and renal survival, adjusting for the percentage of normal glomeruli, histopathologic chronicity index score, and baseline clinical characteristics. Only 5% of patients still dialysis dependent at 4 months subsequently recovered renal function. Low chronicity index score (odds ratio [OR], 1.16; 95% confidence interval [95% CI], 1.04 to 1.30, per unit decrease) and baseline eGFR>10 ml/min per 1.73 m(2) (OR, 2.77; 95% CI, 1.09 to 7.01) were significantly associated with treatment response by 4 months. Among cyclophosphamide-treated patients, the likelihood of treatment response was >14% even with highest chronicity index score and eGFR<10 ml/min per 1.73 m(2).

CONCLUSIONS

Although low baseline renal function and severe renal scarring are associated with lower treatment response rate, no "futility" threshold could be identified. Conversely, continued immunosuppressive therapy beyond 4 months is unlikely to benefit patients who remain dialysis dependent.

Therapeutic plasma exchange for the treatment of pediatric renal diseases in 2013

Therapeutic plasma exchange is an extracorporeal treatment modality that removes systemic circulating pathologic factors or replaces absent plasma components and plays a role in many nephrologic conditions. It presents a number of technical challenges in the pediatric population but has become an increasingly common practice in pediatric nephrology over the past several decades. While prospective evidence is often lacking, our increased understanding of the molecular pathogenesis underlying many pediatric renal diseases provides sound reasoning for the use of plasma exchange in treating these conditions. This review will present the currently accepted indications for plasma exchange in children, the technical aspects of the procedure and its potential complications.

Retrospective analysis of factors predicting end-stage renal failure or death in patients with microscopic polyangiitis with mainly renal involvement

BACKGROUND

The aim of this study was to identify risk factors for end-stage renal failure (ESRF) or death in Japanese patients with microscopic polyangiitis (MPA) with renal involvement.

METHODS

From 54 consecutive patients with systemic vasculitis based on Watt's algorithm, we retrospectively analyzed 39 MPA patients with renal involvement, including 19 (48.7 %) with renal-limited vasculitis.

RESULTS

Thirty-three of 39 patients (84.6 %) demonstrated rapidly progressive glomerulonephritis, and 13 (33.3 %) developed ESRF; 8 of 13 required dialysis within 1 week. Thirteen (33.3 %) died during follow-up of more than 12 months, and 7 died during the first 6 months, mainly because of opportunistic infections. Overall survival at 6 and 12 months was 79.5 and 71.1 %, respectively. Serum creatinine levels did not differ significantly between survivors and non-survivors (P = 0.092). The mean Birmingham Vasculitis Activity Score, version 3 (BVAS v.3), was 16.2 ± 6.5, with a renal subscore of over 12 points in 82.1 %, and BVAS v.3 was marginally higher in non-survivors than survivors (P = 0.045). An age- and sex-adjusted Cox proportional hazards analysis demonstrated that neither the serum creatinine level (P = 0.277) nor BVAS v.3 (P = 0.188) at initial diagnosis was a risk factor for overall survival. The baseline serum creatinine cutoff value for discriminating between ESRF and non-ESRF was 4.6 mg/dl, with a sensitivity and specificity of 92.3 and 84.6 %, respectively.

CONCLUSIONS

Survival rates do not relate to ESRF in MPA patients with mainly renal involvement. Although patients with ESRF required regular hemodialysis, longer survival can be achieved.

Clinical characteristics and outcome of pauci-immune glomerulonephritis in African Americans

OBJECTIVES

Pauci-immune glomerulonephritis is rare in African Americans (AA) and the clinical presentation and treatment outcomes of vasculitis have not been well described.

METHODS

We identified patients who were 2-92 years of age between 1983 and 2011 with a diagnosis of biopsy-proven pauci-immune glomerulonephritis (GN) at any point during their disease course. Comparing AA to Caucasian patients, we examined demographics, clinical features at presentation, treatment and outcomes of relapse, end-stage renal disease (ESRD), and death.

RESULTS

Of the 672 patients, 75 were AA with the remainder being Caucasian. Compared to Caucasians, disease onset in AA was at an earlier age (52 vs. 57 years, p = 0.05) and was more often myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibody (ANCA) positive (71% vs. 54%, p = 0.01). AA patients had a shorter median time between onset of symptoms and biopsy compared to Caucasians [median (IQR): 0.23 (0.00, 1.22) months vs. 0.66 (0.00, 3.62) months, p = 0.003]. Median [Interquartile range (IQR)] follow-up in months was 28 (5, 52) in AA and 26 (10, 55) in Caucasian patients. Median estimated glomerular filtration rate was similar at presentation (21 vs. 22 ml/min/m(2)). Both groups had similar induction treatment regimens. There was less favorable treatment response among AA compared to Caucasians for initial treatment resistance (28% vs. 18%, p = 0.05) and complete remission (72% vs. 82%, p = 0.05). There were no differences in the number of renal relapses or number of deaths between the 2 groups. Overall, in multivariable analyses controlling for age, race, ANCA type, and entry serum creatinine, there were not differences by race in treatment response, renal relapse, ESRD, or death over the entire time of follow-up.

CONCLUSIONS

AA patients with pauci-immune GN are younger and more often MPO-ANCA positive compared to Caucasians. Despite a shorter time to diagnosis for AA patients, there were no differences compared to Caucasians in treatment response, ESRD, renal relapse, or death rates by race over the entire duration of follow-up.