Treatment of progressive membranous glomerulopathy. A randomized trial comparing cyclophosphamide and corticosteroids with corticosteroids alone. The Glomerular Disease Collaborative Network

Efficacy and safety of 12 immunosuppressive agents for idiopathic membranous nephropathy in adults: A pairwise and network meta-analysis

Background: Immunosuppressants have been applied in the remedy of idiopathic membranous nephropathy (IMN) extensively. Nevertheless, the efficacy and safety of immunosuppressants do not have final conclusion. Thus, a pairwise and network meta-analysis (NMA) was carried out to seek the most recommended therapeutic schedule for patients with IMN.

Methods: Randomized controlled trials (RCTs) including cyclophosphamide (CTX), mycophenolate mofetil (MMF), tacrolimus-combined mycophenolate mofetil (TAC + MMF), cyclosporine (CsA), tacrolimus (TAC), leflunomide (LEF), chlorambucil (CH), azathioprine (AZA), adrenocorticotropic hormone (ACTH), non-immunosuppressive therapies (CON), steroids (STE), mizoribine (MZB), and rituximab (RIT) for patients with IMN were checked. Risk ratios (RRs) and standard mean difference (SMD) were reckoned to assess dichotomous variable quantities and continuous variable quantities, respectively. Total remission (TR) and 24-h urine total protein (24-h UTP) were compared using pairwise and NMA. Then interventions were ranked on the basis of the surface under the cumulative ranking curve (SUCRA).

Results: Our study finally included 51 RCTs and 12 different immunosuppressants. Compared with the CON group, most regimens demonstrated better therapeutic effect in TR, with RR of 2.1 (95% CI) (1.5–2.9) for TAC, 1.9 (1.3–2.8) for RIT, 2.5 (1.2–5.2) for TAC + MMF, 1.9 (1.4–2.7) for CH, 1.8 (1.4–2.4) for CTX, 2.2 (1.0–4.7) for ACTH, 1.6 (1.2–2.1) for CsA, 1.6 (1.0–2.5) for LEF, and 1.6 (1.1–2.2) for MMF. In terms of 24-h UTP, TAC (SMD, −2.3 (95% CI −3.5 to −1.1)), CTX (SMD, −1.7 (95% CI −2.8 to −0.59)), RIT (SMD, −1.8 (95% CI −3.5 to −0.11)), CH (SMD, −2.4 (95% CI −4.3 to −0.49)), AZA (SMD, −−4.2 (95% CI −7.7 to −0.68)), and CsA (SMD, −1.7 (95% CI −3 to −0.49)) were significantly superior than the CON group. As for adverse effects (AEs), infections, nausea, emesia, myelosuppression, and glucose intolerance were the collective adverse events for most immunosuppressants.

Conclusion: This study indicates that TAC + MMF performed the best in terms of TR, and TAC shows the best effectiveness on 24-h UTP compared with other regimens. On the contrary, there seems to be little advantage on STE alone, LEF, AZA, and MZB in treating patients with IMN compared with CON.

Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42021287013]

Immunosuppression therapy for idiopathic membranous nephropathy: systematic review with network meta-analysis

BACKGROUND

Idiopathic membranous nephropathy is a common cause of nephrotic syndrome in adults. The Kidney Disease Improving Global Outcomes guidelines recommend rituximab or cyclophosphamide and steroids, or calcineurin inhibitor-based therapy. However, there have been few or no head-to-head comparisons of the relative efficacy and safety of different immunosuppression regimens. We conducted a network meta-analysis to evaluate the comparative efficacy and safety of available immunosuppression strategies compared to cyclophosphamide in adults with idiopathic membranous nephropathy.

METHODS

We performed a systematic search of MEDLINE, Embase and CENTRAL for randomized controlled trials in the treatment of adults with idiopathic membranous nephropathy. The primary outcome was complete remission. Secondary outcomes were kidney failure, partial remission, estimated glomerular filtration rate, doubling of serum creatinine, proteinuria, serious adverse events, discontinuation of treatment, serious infection and bone marrow suppression.

RESULTS

Cyclophosphamide had uncertain effects on inducing complete remission when compared to rituximab (OR 0.35, CI 0.10-1.24, low certainty evidence), mycophenolate mofetil (OR 1.81, CI 0.69-4.71, low certainty), calcineurin inhibitor (OR 1.26, CI 0.61-2.63, low certainty) or steroid monotherapy (OR 2.31, CI 0.62-8.52, low certainty). Cyclophosphamide had a higher probability of inducing complete remission when compared to calcineurin inhibitor plus rituximab (OR 4.45, CI 1.04-19.10, low certainty). Compared to other immunosuppression strategies, there was limited evidence that cyclophosphamide had different effects on other pre-specified outcomes.

CONCLUSIONS

The comparative effectiveness and safety of immunosuppression strategies compared to cyclophosphamide is uncertain in adults with idiopathic membranous nephropathy.

Recent Clinical Trials Insights into the Treatment of Primary Membranous Nephropathy

Immunosuppressive therapy is mandatory for primary membranous nephropathy with persistent nephrotic proteinuria or anti-phospholipase A2 receptor antibodies, reduced kidney function, or another risk factor for progression. Rituximab has demonstrated efficacy for proteinuria remission compared with renin-angiotensin system blockade or cyclosporine in two well-powered randomized controlled trials. More recently, STARMEN showed that alternating glucocorticoid-cyclophosphamide is superior to sequential tacrolimus-rituximab for proteinuria remission, although it was associated with a higher risk of non-serious adverse events. However, sequential tacrolimus-rituximab involved delayed lower dose rituximab and was the worst-performing rituximab regimen among those tested in randomized clinical trials. The RI-CYCLO pilot study did not demonstrate superiority of glucocorticoid-cyclophosphamide over rituximab and found no difference in adverse events. Overall, STARMEN and RI-CYCLO confirmed the efficacy of glucocorticoid-cyclophosphamide in patients with high-risk membranous nephropathy and the role of rituximab as a valid alternative. However, none of the trials tested an optimized rituximab protocol involving a second rituximab cycle before declaring treatment failure. Calcineurin inhibitors should be considered third-line drugs and sequential use of calcineurin inhibitor rituximab did not add over rituximab-only regimens. We critically review recent randomized controlled trials, propose a research agenda, and call for multinational pragmatic trials that enroll patients at referral centers to address unmet research needs.

Immunosuppressive treatment for primary membranous nephropathy in adults with nephrotic syndrome

BACKGROUND

Primary membranous nephropathy (PMN) is a common cause of nephrotic syndrome in adults. Without treatment, approximately 30% of patients will experience spontaneous remission and one third will have persistent proteinuria. Approximately one-third of patients progress toward end-stage kidney disease (ESKD) within 10 years. Immunosuppressive treatment aims to protect kidney function and is recommended for patients who do not show improvement of proteinuria by supportive therapy, and for patients with severe nephrotic syndrome at presentation due to the high risk of developing ESKD. The efficacy and safety of different immunosuppressive regimens are unclear. This is an update of a Cochrane review, first published in 2004 and updated in 2013.

OBJECTIVES

The aim was to evaluate the safety and efficacy of different immunosuppressive treatments for adult patients with PMN and nephrotic syndrome.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 1 April 2021 with support from the Cochrane Kidney and Transplant Information Specialist using search terms relevant to this review. Studies in the Register were 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 (RCTs) investigating effects of immunosuppression in adults with PMN and nephrotic syndrome were included.

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, quality assessment, and data synthesis were performed using Cochrane-recommended methods. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

Sixty-five studies (3807 patients) were included. Most studies exhibited a high risk of bias for the domains, blinding of study personnel, participants and outcome assessors, and most studies were judged unclear for randomisation sequence generation and allocation concealment. Immunosuppressive treatment versus placebo/no treatment/non-immunosuppressive treatment In moderate certainty evidence, immunosuppressive treatment probably makes little or no difference to death, probably reduces the overall risk of ESKD (16 studies, 944 participants: RR 0.59, 95% CI 0.35 to 0.99; I² = 22%), probably increases total remission (complete and partial) (6 studies, 879 participants: RR 1.44, 95% CI 1.05 to 1.97; I² = 73%) and complete remission (16 studies, 879 participants: RR 1.70, 95% CI 1.05 to 2.75; I² = 43%), and probably decreases the number with doubling of serum creatinine (SCr) (9 studies, 447 participants: RR 0.46, 95% CI 0.26 to 0.80; I² = 21%). However, immunosuppressive treatment may increase the number of patients relapsing after complete or partial remission (3 studies, 148 participants): RR 1.73, 95% CI 1.05 to 2.86; I² = 0%) and may lead to a greater number experiencing temporary or permanent discontinuation/hospitalisation due to adverse events (18 studies, 927 participants: RR 5.33, 95% CI 2.19 to 12.98; I² = 0%). Immunosuppressive treatment has uncertain effects on infection and malignancy. Oral alkylating agents with or without steroids versus placebo/no treatment/steroids Oral alkylating agents with or without steroids had uncertain effects on death but may reduce the overall risk of ESKD (9 studies, 537 participants: RR 0.42, 95% CI 0.24 to 0.74; I² = 0%; low certainty evidence). Total (9 studies, 468 participants: RR 1.37, 95% CI 1.04 to 1.82; I² = 70%) and complete remission (8 studies, 432 participants: RR 2.12, 95% CI 1.33 to 3.38; I² = 37%) may increase, but had uncertain effects on the number of patients relapsing, and decreasing the number with doubling of SCr. Alkylating agents may be associated with a higher rate of adverse events leading to discontinuation or hospitalisation (8 studies 439 participants: RR 6.82, 95% CI 2.24 to 20.71; I² = 0%). Oral alkylating agents with or without steroids had uncertain effects on infection and malignancy. Calcineurin inhibitors (CNI) with or without steroids versus placebo/no treatment/supportive therapy/steroids We are uncertain whether CNI with or without steroids increased or decreased the risk of death or ESKD, increased or decreased total or complete remission, or reduced relapse after complete or partial remission (low to very low certainty evidence). CNI also had uncertain effects on decreasing the number with a doubling of SCr, temporary or permanent discontinuation or hospitalisation due to adverse events, infection, or malignancy. Calcineurin inhibitors (CNI) with or without steroids versus alkylating agents with or without steroids We are uncertain whether CNI with or without steroids increases or decreases the risk of death or ESKD. CNI with or without steroids may make little or no difference to total remission (10 studies, 538 participants: RR 1.01, 95% CI 0.89 to 1.15; I² = 53%; moderate certainty evidence) or complete remission (10 studies, 538 participants: RR 1.15, 95% CI 0.84 to 1.56; I² = 56%; low certainty evidence). CNI with or without steroids may increase relapse after complete or partial remission. CNI with or without steroids had uncertain effects on SCr increase, adverse events, infection, and malignancy. Other immunosuppressive treatments Other interventions included azathioprine, mizoribine, adrenocorticotropic hormone, traditional Chinese medicines, and monoclonal antibodies such as rituximab. There were insufficient data to draw conclusions on these treatments.

AUTHORS' CONCLUSIONS

This updated review strengthened the evidence that immunosuppressive therapy is probably superior to non-immunosuppressive therapy in inducing remission and reducing the number of patients that progress to ESKD. However, these benefits need to be balanced against the side effects of immunosuppressive drugs. The number of included studies with high-quality design was relatively small and most studies did not have adequate follow-up. Clinicians should inform their patients of the lack of high-quality evidence. An alkylating agent (cyclophosphamide or chlorambucil) combined with a corticosteroid regimen had short- and long-term benefits, but this was associated with a higher rate of adverse events. CNI (tacrolimus and cyclosporin) showed equivalency with alkylating agents however, the certainty of this evidence remains low. Novel immunosuppressive treatments with the biologic rituximab or use of adrenocorticotropic hormone require further investigation and validation in large and high-quality RCTs.

Substitution of Oral for Intravenous Cyclophosphamide in Membranous Nephropathy

Background

Optimal immunosuppressive treatment for membranous nephropathy is still a matter of controversy. Current recommendations include oral cyclophosphamide combined with steroids (modified Ponticelli regimen) as first-line treatment in patients who are high risk. However, concerns about the cumulative toxicity of oral cyclophosphamide persist. In the last 30 years, a protocol based on low-dose intravenous cyclophosphamide plus steroids has been used to treat membranous nephropathy in Uruguay. We aimed to assess the efficacy of this regimen to induce clinical remission in patients with membranous nephropathy.

Methods

In this retrospective, observational cohort study, we analyzed the outcome of 55 patients with membranous nephropathy treated between 1990 and 2017 with a 6-month course of alternating steroids (months 1, 3, and 5) plus intravenous cyclophosphamide (single dose of 15 mg/kg on the first day of months 2, 4, and 6).

Results

At 24 months, 39 (71%) patients achieved clinical response with complete remission observed in 23 patients (42%) and partial remission in 16 (29%). Median time to achieve partial and complete remission was 5.9 and 11.5 months, respectively. Absence of response was observed in 16 patients (29%), five of whom started chronic RRT after a median follow-up of 3.5 years. Clinical relapse occurred in nine of 33 (27%) patients at a median of 34 months after treatment discontinuation.

Conclusions

Replacement of oral cyclophosphamide with a single intravenous pulse on months 2, 4, and 6 of the modified Ponticelli regimen can be an effective and safe alternative for treatment of membranous nephropathy.

Podcast

This article contains a podcast at https://www.asn-online.org/media/podcast/K360/2020_09_24_KID0002802020.mp3

Comparative efficacy of 13 immunosuppressive agents for idiopathic membranous nephropathy in adults with nephrotic syndrome: a systematic review and network meta-analysis

OBJECTIVES

This study aimed to compare the effectiveness of 13 types of immunosuppressive agents used to treat idiopathic membranous nephropathy (IMN) in adults with nephrotic syndrome.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

PubMed, EMbase, Cochrane Library, Web of Science, Clinical trials, SinoMed, Chinese Biomedicine, CNKI, WanFang and Chongqing VIP Information databases were comprehensively searched until February 2018.

ELIGIBILITY CRITERIA

Randomised clinical trials (RCTs) comparing the effects of different immunosuppressive treatments in adult patients with IMN and nephrotic syndrome were included, and all included RCTs had a study-duration of at least 6 months.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened articles, extracted data and assessed study quality. Standard pairwise meta-analysis was performed using DerSimonian-Laird random-effects model.

RESULTS

This study ultimately included 48 RCTs with 2736 patients and 13 immunosuppressive agents. The network meta-analysis results showed that most regimens, except for leflunomide (LEF), mizoribine (MZB) and steroids (STE), showed significantly higher probabilities of total remission (TR) when compared with non-immunosuppressive therapies (the control group),with risk ratios (RRs) of 2.71 (95% CI) 1.81 to 4.06)for tacrolimus+tripterygium wilfordii (TAC+TW), 2.16 (1.27 to 3.69) foradrenocorticotropic hormone, 2.02 (1.64 to 2.49) for TAC, 2.03 (1.13 to3.64) for azathioprine (AZA), 1.91 (1.46 to 2.50) for cyclosporine (CsA), 1.86 (1.44 to2.42) for mycophenolate mofetil (MMF), 1.85 (1.52 to 2.25) for cyclophosphamide (CTX),1.81 (1.10 to 2.98) for rituximab (RIT), 1.80 (1.38 to 2.33) for TW, 1.72 (1.35 to 2.19) for chlorambucil. As for 24 hours UTP, the direct andindirect comparisons showed that AZA (standard mean difference (SMD), -1.02(95% CI -1.90 to -0.15)), CsA (SMD, -0.70 (95% CI -1.33 to -0.08)),CTX (SMD, -1.01 (95% CI -1.44 to -0.58)), MMF (SMD, -0.98 (95% CI -1.64 to -0.32)), MZB (SMD, -0.97 (95% CI -1.90 to-0.04]), TAC (SMD, -1.16 (95% CI -1.72 to -0.60)) and TAC+TW(SMD, -2.03 (95% CI -2.94 to -1.12)) could significantly superior thancontrol, except for chlorambucil, LEF, RIT and STE. Thechanges of serum creatinine (Scr) was not significantly different between eachtreatments of immunosuppressive agents and the control, except for STE whichhas the possibility of increasing Scr (SMD, 1.00 (95% CI 0.36 to 1.64)).Comparisons among all treatments of immunosuppressive agents showed nostatistical significance in the outcome of relapse. A drenocorticotropichormone (85.1%) showed the lowest probability of relapse under the cumulativeranking curve values among all immunosuppressants. Infection,gastrointestinal symptoms, and bone marrow suppression were the common adverseevents associated with most of the immunosuppressive therapies.

CONCLUSIONS

This study demonstrates that TAC+TW, TAC and CTX are superior to other immunosuppressive agents in terms of TR and 24 hours UTP. Moreover, they are all at risk of infection, gastrointestinal symptoms, and myelosuppression. Furthermore, TAC could increase the risk of glucose intolerance or new-onset diabetes mellitus. Conversely, STE alone, LEF and MZB seem to have little advantage in clinical treatment of IMN.

PROSPERO REGISTRATION NUMBER

CRD42018094228.

Intravenous pulse cyclophosphamide and steroids induce immunological and clinical remission in New-incident and relapsing primary membranous nephropathy

AIM

Primary membranous nephropathy is associated with progression to end stage renal diseasein some patients. Standard therapy with cyclical cyclophosphamide and corticosteroids can be associated with significant adverse effects. We aimed to assess immunological and clinical response with intravenous pulse cyclophosphamide and oral steroids in patients with severe nephrotic syndrome - in a prospective observational cohort study.

METHODS

A total of 17 consecutive patients (nine new-incident and eight relapses) with severe nephrotic syndrome received monthly intravenous pulse cyclophosphamide and oral steroids after failure to achieve remission with supportive therapy. Immunosuppressive therapy was discontinued at 6 months or earlier if proteinuria regressed to <100 mg/mmol and patients were followed for 12 months. Achievement of partial remission was primary outcome; changes in clinical parameters and anti-PLA₂ R were secondary outcomes.

RESULTS

Dose of cyclophosphamide received was 5.4 g in New-incident patients and 4.2 g in patients with relapses. All 17 patients achieved partial remission within 6 months: proteinuria improved from 656 to 102 mg/mmol at 6 months and 55 mg/mmol at 12 months (P < 0.001); eGFR improved from 31 to 48 mL/min per 1.73 m² at 6 months and 45 mL/min per 1.73 m² at 12 months (P < 0.05). Anti-PLA₂ R levels reduced from 244 to 10 U/L at 6 months and 10 U/L at 12 months (P < 0.001). Two out of nine patients in the New-incident group developed subsequent relapse. Cumulative doses of cyclophosphamide and steroids that patients received was about half of the standard regime.

CONCLUSION

Pulse cyclophosphamide with oral steroids induced immunological and clinical partial remission at significantly reduced doses in primary membranous nephropathy.

Comparative effectiveness and tolerance of immunosuppressive treatments for idiopathic membranous nephropathy: A network meta-analysis

Background

Immunosuppressive agents in general are shown to prevent renal progression and all-cause mortality in idiopathic membranous nephropathy (IMN) patients with nephrotic syndrome. However, the efficacy and safety of different immunosuppressive treatments have not been systematic assessed and compared. A network meta-analysis was performed to compare different immunosuppressive treatment in IMN.

Methods

Cochrane library, MEDLINE, EMBASE and trial register system were searched for randomized controlled trials reporting the treatments for IMN to May 3, 2016. Composite endpoint of mortality or end-stage kidney disease (ESKD), complete or partial proteinuria remission and withdrawal because of treatment adverse events were compared combing direct and indirect comparison using network meta-analysis. Ranking different immunosuppressive treatments in the outcomes were analyzed by using surface under the cumulative ranking curve (SUCRA).

Results

Total 36 randomized controlled trials (n = 2018) covering 11 kinds of treatments were included. Compared with non-immunosuppressive treatment, only cyclophosphamide (CTX) and chlorambucil significantly reduced the risk of composite outcome of mortality or ESKD while combining the direct and indirect comparison (OR = 0.31, 95%CI: 0.12–0.81 and OR = 0.33, 95%CI: 0.12–0.92). CTX increased the composite outcome of complete remission (CR) or partial remission (PR) (OR = 4.29, 95%CI: 2.30–8.00) but chlorambucil did not (OR = 1.58, 95%CI: 0.80–3.12) as compared with non-immunosuppressive treatment. Chlorambucil also significantly increased the withdrawal risk (OR = 3.34, 95%CI: 1.37–8.17) as compared to CTX. Both tacrolimus (OR = 3.10, 95%CI: 1.36–7.09) and cyclosporine (CsA) (OR = 2.81, 95%CI: 1.08–7.32) also significantly increased the rate of CR or PR as compared with non-immunosuppressive treatment (without significant difference as compared with CTX), while ranking results showed that cyclosporine or tacrolimus was with less possibility of drug withdrawal as compared to CTX.

Conclusions

Cyclophosphamide and chlorambucil reduce risk of ESKD or death in IMN with nephrotic range proteinuria, but carry substantial toxicity that may be lower for cyclophosphamide. Tacrolimus and cyclosporine increase the possibility of proteinuria remission with less drug withdrawal, but the effects on kidney failure remain uncertain.

Long-term outcomes of persistent disease and relapse in primary membranous nephropathy

BACKGROUND

Primary membranous nephropathy is associated with variable clinical course ranging from spontaneous remission to slow progression to end stage renal failure. Achieving remission confers better renal survival in primary membranous nephropathy (PMN). Longer term outcomes such as patient survival and relapse of active disease remain poorly understood.

METHODS

We performed a retrospective study of 128 consecutive adult patients diagnosed with biopsy proven PMN at a single UK centre between 1980 and 2010. These patients were followed prospectively over a median of 128 months. We assessed impact of persistent disease and relapse on Stage 5 chronic kidney disease (CKD-5) and patient survival and present longer term cumulative incidences of different end points.

RESULTS

One hundred patients achieved partial remission (PartRem) and 28 patients did not achieve remission (NoRem). Nine per cent of patients achieving first remission developed CKD-5 and 75% of those with NoRem developed CKD-5 [hazard ratio (HR) 0.07, 95% confidence interval 0.03-0.19). Relapse following PartRem occurred in 31 patients (31%) during follow-up and was significantly associated with progression to CKD-5. Progression to CKD-5 was strongly associated with death (47 versus 6%, HR 23.4; P < 0.01). Cumulative incidence at 15 years following first presentation included: death, 14%; CKD-5, 28%; and relapse 40% (in patients who achieved first remission).

CONCLUSIONS

Our data strongly suggest that mortality in PMN is seen in patients with disease progression to CKD-5. Achieving remission is strongly associated with improved renal survival after first presentation and following relapse. We suggest that patients who achieve remission should be followed up in longer term, and better strategies to help improve outcomes are needed in clinical practice.

Immunosuppressive treatment for idiopathic membranous nephropathy in adults with nephrotic syndrome

BACKGROUND

Idiopathic membranous nephropathy (IMN) is the most common form of nephrotic syndrome in adults. The disease shows a benign or indolent course in the majority of patients, with a rate of spontaneous complete or partial remission of nephrotic syndrome as high as 30% or more. Despite this, 30% to 40% of patients progress toward end-stage kidney disease (ESKD) within five to 15 years. The efficacy and safety of immunosuppression for IMN with nephrotic syndrome are still controversial. This is an update of a Cochrane review first published in 2004.

OBJECTIVES

The aim of this review was to evaluate the safety and efficacy of immunosuppressive treatments for adult patients with IMN and nephrotic syndrome. Moreover it was attempted to identify the best therapeutic regimen, when to start immunosuppression and whether the above therapies should be given to all adult patients at high risk of progression to ESKD or only restricted to those with impaired kidney function.

SEARCH METHODS

We searched Cochrane Renal Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Chinese databases, reference lists of articles, and clinical trial registries to June 2014. We also contacted principal investigators of some of the studies for additional information.

SELECTION CRITERIA

Randomised controlled trials (RCTs) investigating the effects of immunosuppression in adults with IMN and nephrotic syndrome.

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, quality assessment, and data synthesis were performed using the Cochrane-recommended methods. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes.

MAIN RESULTS

Thirty nine studies with 1825 patients were included, 36 of these could be included in our meta-analyses. The data from two studies could not be extracted and one study was terminated due to poor accrual. Immunosuppression significantly reduced all-cause mortality or risk of ESKD ((15 studies, 791 patients): RR 0.58 (95% CI 0.36 to 0.95, P = 0.03) and risk of ESKD ((15 studies, 791 patients): RR 0.55, 95% CI 0.31 to 0.95, P = 0.03), increased complete or partial remission ((16 studies, 864 patients): RR 1.31, 95% CI 1.01 to 1.70, P = 0.04), and decreased proteinuria ((9 studies,(393 patients): MD -0.95 g/24 h, 95% CI -1.81 to -0.09, P = 0.03) at the end of follow-up (range 6 to 120 months). However this regimen was associated with more discontinuations or hospitalisations ((16 studies, 880 studies): RR 5.35, 95% CI 2.19 to 13.02), P = 0.0002). Combined corticosteroids and alkylating agents significantly reduced death or risk of ESKD ((8 studies, 448 patients): RR 0.44, 95% CI 0.26 to 0.75, P = 0.002) and ESKD ((8 studies, 448 patients): RR 0.45, 95% CI 0.25 to 0.81, P = 0.008), increased complete or partial remission ((7 studies, 422 patients): RR 1.46, 95% CI 1.13 to 1.89, P = 0.004) and complete remission ((7 studies, 422 patients): RR 2.32, 95% CI 1.61 to 3.32, P < 0.00001), and decreased proteinuria ((6 studies, 279 patients): MD -1.25 g/24 h, 95% CI -1.93 to -0.57, P = 0.0003) at the end of follow-up (range 9 to 120 months). In a population with an assumed risk of death or ESKD of 181/1000 patients, this regimen would be expected to reduce the number of patients experiencing death or ESKD to 80/1000 patients (range 47 to 136). In a population with an assumed complete or partial remission of 408/1000 patients, this regimen would be expected to increase the number of patients experiencing complete or partial remission to 596/1000 patients (range 462 to 772). However this combined regimen was associated with a significantly higher risk of discontinuation or hospitalisation due to adverse effects ((4 studies, 303 patients): RR 4.20, 95% CI 1.15 to 15.32, P = 0.03). Whether this combined therapy should be indicated in all adult patients at high risk of progression to ESKD or only restricted to those with deteriorating kidney function still remained unclear. Cyclophosphamide was safer than chlorambucil ((3 studies, 147 patients): RR 0.48, 95% CI 0.26 to 0.90, P = 0.02). There was no clear evidence to support the use of either corticosteroid or alkylating agent monotherapy. Cyclosporine and mycophenolate mofetil failed to show superiority over alkylating agents. Tacrolimus and adrenocorticotropic hormone significantly reduced proteinuria. The numbers of corresponding studies related to tacrolimus, mycophenolate mofetil, adrenocorticotropic hormone, azathioprine, mizoribine, and Tripterygium wilfordii are still too sparse to draw final conclusions.

AUTHORS' CONCLUSIONS

In this update, a combined alkylating agent and corticosteroid regimen had short- and long-term benefits on adult IMN with nephrotic syndrome. Among alkylating agents, cyclophosphamide was safer than chlorambucil. This regimen was significantly associated with more withdrawals or hospitalisations. It should be emphasised that the number of included studies with high-quality design was relatively small and most of included studies did not have adequate follow-up and enough power to assess the prespecified definite endpoints. Although a six-month course of alternating monthly cycles of corticosteroids and cyclophosphamide was recommended by the KDIGO Clinical Practice Guideline 2012 as the initial therapy for adult IMN with nephrotic syndrome, clinicians should inform their patients of the lack of high-quality evidence for these benefits as well as the well-recognised adverse effects of this therapy. Cyclosporine or tacrolimus was recommended by the KDIGO Clinical Practice Guideline 2012 as the alternative regimen for adult IMN with nephrotic syndrome; however, there was no evidence that calcineurin inhibitors could alter the combined outcome of death or ESKD.

Immunosuppression for membranous nephropathy: a systematic review and meta-analysis of 36 clinical trials

BACKGROUND AND OBJECTIVES

The efficacy and safety of immunosuppression for idiopathic membranous nephropathy (IMN) with nephrotic syndrome are still controversial. A systematic review and meta-analysis of randomized controlled trials (RCTs) was performed.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Cochrane Library, PUBMED, EMBASE, Chinese Database, and Clinical Trial Registries (June 2012) were searched to identify RCTs investigating the effect of immunosuppression on adults with IMN and nephrotic syndrome.

RESULTS

This review was an update (36 RCTs, 1762 participants) of the 2004 version (18 RCTs, 1025 participants). Immunosuppression significantly reduced all-cause mortality or ESRD (15 RCTs, 791 participants; risk ratio, 0.58 [95% confidence interval, 0.36-0.95]; P=0.03). However, the result was not consistent when prespecified subgroup analyses were undertaken. Immunosuppression increased complete or partial remission (CR + PR) (16 RCTs, 864 participants; 1.31 [1.01-1.70]; P=0.04) but resulted in more withdrawals or hospitalizations (16 RCTs, 880 participants; 5.35 [2.19-13.02]; P=0.002). Corticosteroids combined with alkylating agents significantly reduced all-cause mortality or ESRD (8 RCTs, 448 participants; 0.44 [0.26-0.75]; P=0.002) and increased CR + PR (7 RCTs, 422 participants; 1.46 [1.13-1.89]; P=0.004) but led to more adverse events (4 RCTs, 303 participants; 4.20 [1.15-15.32]; P=0.03). Cyclophosphamide was safer than chlorambucil (3 RCTs, 147 participants; 0.48 [0.26-0.90]; P=0.02). Cyclosporine and mycophenolate mofetil failed to show superiority over alkylating agents. Tacrolimus and adrenocorticotropic hormone significantly reduced proteinuria.

CONCLUSIONS

Alkylating agents plus corticosteroids had long-term and short-term benefits for adult IMN, but resulted in more withdrawals or hospitalizations.

Venous thromboembolism in patients with membranous nephropathy

BACKGROUND AND OBJECTIVES

The aims of this study were to determine the frequency of venous thromboembolic events in a large cohort of patients with idiopathic membranous nephropathy and to identify predisposing risk factors.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied patients with biopsy-proven membranous nephropathy from the Glomerular Disease Collaborative Network (n=412) and the Toronto Glomerulonephritis Registry (n=486) inception cohorts. The cohorts were pooled after establishing similar baseline characteristics (total n=898). Clinically apparent and radiologically confirmed venous thromboembolic events were identified. Potential risk factors were evaluated using multivariable logistic regression models.

RESULTS

Sixty-five (7.2%) subjects had at least one venous thromboembolic event, and this rate did not differ significantly between registries. Most venous thromboembolic events occurred within 2 years of first clinical assessment (median time to VTE = 3.8 months). After adjusting for age, sex, proteinuria, and immunosuppressive therapy, hypoalbuminemia at diagnosis was the only independent predictor of a venous thromboembolic event. Each 1.0 g/dl reduction in serum albumin was associated with a 2.13-fold increased risk of VTE. An albumin level <2.8 g/dl was the threshold below which risk for a venous thromboembolic event was greatest.

CONCLUSIONS

We conclude that clinically apparent venous thromboembolic events occur in about 7% of patients with membranous nephropathy. Hypoalbuminemia, particularly <2.8 g/dl, is the most significant independent predictor of venous thrombotic risk.

Idiopathic membranous nephropathy: management strategies

Treatment of idiopathic membranous nephropathy is based on a 'symptomatic' therapy that includes ACE inhibitors or angiotensin II receptor antagonists, and on an 'aetiological' therapy aimed at modulating underlying immunological mechanisms. The role of the latter is still debated given the usually indolent course of disease; furthermore, traditional immunosuppressants would not have an impact on patient and renal survival according to a systematic review of literature. However, up to 40% of untreated patients eventually develop end-stage renal disease and remission of nephrotic syndrome protects patients from related life-threatening complications and is the strongest positive prognostic factor for long-term kidney function. Therefore, immunosuppressive therapy seems to be rational in high-risk patients with nephrotic syndrome or deteriorating renal function. This article outlines a possible role for each 'aetiological' therapy on the basis of available evidence in order to provide some practical recommendations. The first-line therapy is based on a 6-month regimen of alternating corticosteroids and an alkylating agent ('Ponticelli' regimen), whereas oral ciclosporin and intramuscular corticotrophin (adrenocorticotrophic hormone) are alternatives that provide comparable results in terms of remission of proteinuria, with a different adverse effect profile. New drugs are emerging as potential treatments, such as mycophenolate mofetil, tacrolimus, intravenous immunoglobulins and rituximab. Specific settings, such as chronic renal failure or elderly age, require a careful balance between benefits and toxicity of immunosuppression. The tailor-made use of this repertoire of drugs can provide a tool to achieve remission of proteinuria and modify the natural course of idiopathic membranous nephropathy.

Controversies in the treatment of idiopathic membranous nephropathy

Optimum treatment of idiopathic membranous nephropathy is both controversial and challenging. The most extensively studied and frequently used immunosuppressive regimens for this disease comprise alkylating agents plus corticosteroids or ciclosporin. All of these treatment options have inherent problems: they are not effective in all patients, partial-rather than complete-remissions are common, adverse effects are worrisome, and relapses after treatment cessation remain problematic. Alternative immunosuppressive agents have been tested in an effort to overcome these unresolved issues. This paper reviews the available evidence regarding both established and new agents for the treatment of patients with idiopathic membranous nephropathy, with an emphasis on the results of the most recent clinical trials.

Mycophenolate mofetil in idiopathic membranous nephropathy: a clinical trial with comparison to a historic control group treated with cyclophosphamide

BACKGROUND

Cyclophosphamide can decrease proteinuria and improve renal function in patients with idiopathic membranous nephropathy, but has a high risk of side effects. We studied whether mycophenolate mofetil (MMF) could be a reasonable alternative with fewer side effects.

STUDY DESIGN

Clinical trial with historic controls.

SETTINGS & PARTICIPANTS

32 cases and 32 controls with idiopathic membranous nephropathy and renal insufficiency at multiple centers. For comparison, we selected matched historic controls treated with cyclophosphamide.

INTERVENTION

MMF, 1 g twice daily, for 12 months versus cyclophosphamide, 1.5 mg/kg/d, for 12 months. Both groups also received intermittent methylprednisolone and alternate-day prednisone.

OUTCOMES & MEASUREMENTS

Serum creatinine, proteinuria, and side effects during and after treatment.

RESULTS

Median follow-up was 23 months (range, 11 to 46 months). Median serum creatinine levels were 1.8 mg/dL (159 micromol/L) in both groups at baseline and 1.4 mg/dL (124 micromol/L) in the MMF group versus 1.3 mg/dL (115 micromol/L) in the cyclophosphamide group at 12 months (P = 0.4). Proteinuria values at baseline and 12 months were protein of 8.40 and 1.41 g/d in the MMF group versus 9.19 and 1.13 g/d in the cyclophosphamide group (P = 0.5 at 12 months), respectively. Cumulative incidences of remission of proteinuria at 12 months were 66% in the MMF group versus 72% in the cyclophosphamide group (P = 0.3). Five patients (16%) in the MMF group versus none in the cyclophosphamide group had disease that did not respond to therapy (P = 0.05). Twelve patients (38%) experienced a relapse and 9 patients (31%) were re-treated in the MMF group compared with 4 (13%) and 2 patients (6%) in the cyclophosphamide group (P < 0.01 and P = 0.024, respectively). Side effects occurred in 24 patients (75%) in the MMF group and 22 patients (69%) in the cyclophosphamide group (P = 0.6).

LIMITATIONS

Nonrandomized control group, short duration of follow-up.

CONCLUSIONS

A 12-month course of MMF decreased proteinuria and improved renal function in the majority of patients, but did not appear as effective or better tolerated than cyclophosphamide. Long-term data and randomized controlled trials are needed to ascertain the efficacy of MMF in patients with idiopathic membranous nephropathy.

A randomized, controlled trial of steroids and cyclophosphamide in adults with nephrotic syndrome caused by idiopathic membranous nephropathy

Idiopathic membranous nephropathy (IMN) is the most common cause of nephrotic syndrome in adults. Universal consensus regarding the need for and the modality of therapy has not been formed because of a lack of controlled trials of sufficient size, quality, and duration. This study compared the effect of a 6-mo course of alternating prednisolone and cyclophosphamide with supportive treatment in adults with nephrotic syndrome caused by IMN on doubling of serum creatinine, development of ESRD, and quality of life in a randomized, controlled trial. Patients were followed up for 10 yr. Data were analyzed on an intention-to-treat basis. A total of 93 patients completed the study. Of the 47 patients who received the experimental protocol, 34 achieved remission (15 complete and 19 partial), compared with 16 (five complete, 11 partial) of 46 in the control group (P < 0.0001). The 10-yr dialysis-free survival was 89 and 65% (P = 0.016), and the likelihood of survival without death, dialysis, and doubling of serum creatinine were 79 and 44% (P = 0.0006) in the two groups. Treated patients exhibited significantly lower prevalence of edema, hypertension, hypoalbuminemia, hyperlipidemia that required therapy, angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker use, and better quality of life on follow-up. The incidence of infections was similar in the two groups. In conclusion, untreated IMN with nephrotic syndrome is associated with a high risk for deterioration of renal function. A 6-mo regimen of cyclophosphamide and steroids induces remissions in a high proportion, arrests progression of renal insufficiency, and improves quality of life.

Controversies in small vessel vasculitis--comparing the rheumatology and nephrology views

Over the past 20 years, remarkable progress has been made in understanding the pathogenesis and treatment of patients with small vessel vasculitis. Nephrologists and rheumatologists play primary roles in the care of these patients. Whilst there are many areas of agreement between these specialists with respect to understanding and practical care of these patients, there are a number of important areas that differ in the practice patterns of nephrologic and rheumatologic practice. These areas include the nomenclature of these diseases, the role of antineutrophil cytoplasmic antibodies in the pathogenesis, the route and duration of initial cyclophosphamide administration, and, most importantly, the total duration of maintenance therapy following disease remission. Two experienced clinicians, a rheumatologist and a nephrologist, spar off in support of their opinions.

Idiopathic Membranous Nephropathy: Outline and Rationale of a Treatment Strategy

Idiopathic membranous nephropathy is a common cause of nephrotic syndrome. The treatment of patients with idiopathic membranous nephropathy is heavily debated. Based on literature data and our own experience, we propose a rational treatment strategy. Patients with renal insufficiency (serum creatinine level > 1.5 mg/dL [> 135 micromol/L]) are at greatest risk for the development of end-stage renal disease and should receive immunosuppressive therapy. In patients with normal renal function (serum creatinine level < 1.5 mg/dL [< 135 micromol/L]), risk for developing end-stage renal disease can be estimated by measuring urinary excretion of beta2-microglobulin or alpha1-microglobulin and immunoglobulin G. For low-risk patients, a wait-and-see policy is advised. High-risk patients likely benefit from immunosuppressive therapy. Currently, combinations of steroids with chlorambucil or cyclophosphamide are the best studied. We prefer cyclophosphamide in view of its fewer side effects. Cyclosporine may be an alternative option in patients with well-preserved renal function, although long-term data are lacking. Other immunosuppressive agents, such as mycophenolate mofetil or rituximab, currently are under study; however, data are insufficient to support their routine use.

Immunosuppressive treatment for idiopathic membranous nephropathy in adults with nephrotic syndrome

BACKGROUND

Idiopathic membranous nephropathy (IMN) is the most common form of nephrotic syndrome in adults. The disease shows a benign or indolent course in the majority of patients, with a rate of spontaneous complete or partial remission of nephrotic syndrome as high as 30% or more. Despite this, 30-40% of patients progress toward end-stage renal failure (ESRF) within 5-15 years.

OBJECTIVES

To assess the benefits and harms of immunosuppressive treatment for IMN in adults.

SEARCH STRATEGY

We searched the Cochrane Renal Group Specialised Register (December 2003), The Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 4, 2003), MEDLINE and Pre-MEDLINE (1966 - December 2003), EMBASE (1980 - December 2003), reference lists of nephrology textbooks, review articles, prospective trial registers, relevant trials and abstracts from nephrology scientific meetings and the internet without language restriction. We also contacted principal investigators of controlled studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing any immunosuppressive interventions for the treatment of IMN in adults.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed and extracted information. Information was collected on method, participants, interventions and outcomes (death, ESRF, proteinuria, serum creatinine, GRF, remission, adverse events).

MAIN RESULTS

A total of 18 trials with 1025 patients were included. No differences were found when we combined data of all treatment categories as a group and compared them with placebo or no treatment. Oral glucocorticoids. No beneficial effect on any of the end points chosen for efficacy was observed. Alkylating agents showed a significant beneficial effect on complete remission (RR 2.37, 95%CI 1.32 to 4.25, P = 0.004) but not on partial remission (RR 1.22, 95%CI 0.63 to 2.35, P = 0.56) or complete or partial remission (RR 1.55, 95%CI 0.72 to 3.34, P = 0.27). Cyclophosphamide treatment resulted in significantly lower rate of discontinuations due to adverse events as compared to chlorambucil (RR 2.34, 95%CI 1.25 to 4.39, P = 0.008). There was no evidence of clinically relevant differences in favour of cyclosporin and there was insufficient data on anti-proliferative agents.

REVIEWERS' CONCLUSIONS

This review failed to show any long-term effect of immunosuppressive treatment on patient and/or renal survival. There was an increased number of discontinuations due to adverse events in immunosuppressive treatment groups. Within the class of alkylating agents there is weak evidence supporting the efficacy of cyclophosphamide as compared to chlorambucil. On the other hand, cyclophosphamide had fewer side effects leading to patient withdrawal than chlorambucil.

Developments in the Immunotherapy of Glomerular Disease

Glomerular diseases span a broad spectrum of clinical syndromes, with varied clinical manifestations, underlying etiologies, and pathogenic mechanisms. They can be secondary to underlying infectious, toxic, environmental, or drug exposures, or present as “primary entities.” In the latter case, most glomerular diseases are thought to be due to autoimmune dysregulation, and their treatment is primarily immunosuppressive. The armamentarium for immunomodulation includes corticosteroids, alkylating agents, anti-metabolites, calcineurin inhibitors, and new biological agents designed to block specific inflammatory pathways. The choice of therapy for an individual patient must be based on the specific character of the glomerular disease and its acuity and severity, as well as the patient’s comorbidities, history of prior exposure to immunosuppressive drugs, and risk factors for developing complications of the disease or its treatment. The complexities of such therapy can best be addressed by an experienced team of care givers in which the clinical pharmacist can help minimize, if not eliminate, potential sources of drug induced toxicities and adverse effects. This article will describe the major agents and modalities used in the management of the most common glomerular diseases.

Pharmacological management of membranous nephropathy

When steroids and immunosuppressive drugs were the only available pharmacological agents used to treat membranous nephropathy, nephrologists were polarized into two groups, those supporting therapy on the basis of the results achieved in controlled trials and those opposed to therapy who contended that the side-effects of therapy were too severe to consider in a disease with a relatively benign course. These two groups are drawing closer as treatments with lesser side-effects emerge. The demonstration that proteinuria accelerates progressive kidney failure in all renal diseases led to a major focus on control of proteinuria. Angiotensin-converting enzyme inhibitors, diuretics and angiotensin II receptor antagonists all play a role. Older methods of treatment that reduce proteinuria are being resurrected. A major development is the demonstration in a randomized study that cyclosporin A is effective in membranous nephropathy. Therefore, although there has been no major recent breakthrough or novel therapeutic agent used in membranous nephropathy, a range of new methods of controlling proteinuria provide some compromise between therapeutic enthusiasm and conservative management in this common disorder.

Conservative versus immunosuppressive treatment of patients with idiopathic membranous nephropathy

BACKGROUND

Treatment of idiopathic membranous glomerulonephritis (MGN) is a controversial issue. Whereas some authors recommend early immunosuppressive treatment of all patients with nephrotic syndrome, others do not support aggressive therapies, based on the spontaneous long-term favorable outcome of most patients. However, 20 to 50% of untreated patients develop progressive renal insufficiency.

METHODS

All of the patients with biopsy-proven MGN who developed renal insufficiency at our Hospital during the period of 1975 to 2000 were studied. Selected patients (N=39) were separated into two groups according to the two different therapeutic policies followed at our department: a conservative approach during the first period, 1975 to 1989 (group I, N=20), and a course of immunosuppressive therapy (oral prednisone for six months and concurrent oral chlorambucil, 0.15 mg/kg/day, during the first 14 weeks) during the second period, 1990 to 2000 (group II, N=19).

RESULTS

There were no significant differences between both groups at the time of renal biopsy, nor at the onset of renal function decline. All group I patients showed a progressive renal insufficiency; at the end of the follow-up 13 patients (65%) were on chronic dialysis, 2 (10%) showed advanced renal failure, and 5 (25%) had died. In contrast, most of group II patients showed an improvement or stabilization of serum creatinine (SCr; 2.3 +/- 0.9 mg/dL at onset of treatment, 2 +/- 1.5 mg/dL at the end of follow-up) together with decreased proteinuria (11.2 +/- 3.3 vs. 5.2 +/- 6.7 g/24 h). At the end of the follow-up 58% of group II patients had a SCr value < or =1.5 mg/dL and 36% showed a complete or partial remission, whereas no patient in group I showed remission. After four years of follow-up the probability of renal survival without dialysis was 55% in group I and 90% in group II (P < 0.001), and after seven years the renal survival was 20% and 90%, respectively (P < 0.001). Side effects of immunosuppressive treatment were uncommon but severe, as two patients suffered Pneumocystis carinii pneumonia.

CONCLUSION

A course of immunosuppressive treatment administered early at the onset of renal function decline induces a favorable effect in most of patients with MGN and deteriorating renal function. Untreated patients progressed without exception toward advanced renal failure.

New Aspects of the Treatment of Nephrotic Syndrome

Abstract.The nephrotic syndrome, caused by glomerulonephritis, diabetes mellitus, or amyloidosis, is still a therapeutic challenge. Newer therapeutic approaches may be sought in the fields of immunosuppression, nonspecific supportive measures, heparinoid administration, and removal of a supposed glomerular basement membrane toxic factor. In immunosuppression, the newer drugs now used in organ transplantation (cyclosporine, tacrolimus, and mycophenolate mofetil) can also be used in the treatment of glomerulonephritis. In nonspecific supportive treatment, angiotensin II receptor antagonists are now used in addition to angiotensin-converting enzyme inhibitors. Positive effects of hydroxymethylglutaryl coenzyme A reductase inhibitors on the nephrotic syndrome have not yet been proven. Cyclooxygenase II inhibitors must be tested but probably have too many renal side effects, similar to those of nonsteroidal anti-inflammatory drugs. Heparinoids or glycosaminoglycans serve as polyanions and thus have protective effects on the negative charge of the glomerular basement membrane. They can now be administered as oral medications. The removal of a supposed glomerular basement membrane toxic factor that induces proteinuria has been attempted for 20 yr and now is usually performed using immunoadsorption. Especially in cases of recurrent nephrotic syndrome after renal transplantation for patients with glomerulonephritis, this approach has been successful in decreasing proteinuria, although in most cases its effect is not lasting but must be continuously renewed.

Treatment of idiopathic membranous nephropathy (IMN)

The best treatment of idiopathic membranous nephropathy remains an area of clinical controversy. At the moment only patients with nephrotic syndrome and/or declining renal function should be treated. Despite the negative trials, prolonged oral administration of corticosteroids alone may be a safe and an effective first-line treatment in nephrotic patients. If corticosteroids are ineffective, prolonged use of cyclosporine in low-doses can be recommended as an alternative treatment, that diminishes rapidly proteinuria in the majority of patients. Both treatments (intravenous high doses of corticosteroids and cyclosporine) may also be effective in patients with declining renal function. Because of their toxicity, the routine use of alkylating agents for patients with nephrotic syndrome is not justified. They may be retained for patients, in whom other treatment modalities have failed. Chlorambucil may be preferred over cyclophosphamide since it carries less toxicity. A lower dose of chlorambucil, than that usually suggested, for a short period of time seems to be prudent in an effort to avoid serious side-effects.

Use of mycophenolate mofetil in resistant membranous nephropathy

Membranous nephropathy (MN) is a common cause of nephrotic syndrome. Optimal therapy for this disease is still debated. We report our experience using mycophenolate mofetil (MMF), an immunosuppressive agent widely used in transplant recipients, to treat 16 nephrotic patients with MN. All patients had biopsy-documented MN; secondary forms were ruled out. Fifteen patients had steroid-resistant disease; cytotoxic agents had failed in 6 patients and cyclosporine therapy had failed in 5 patients. Patients were treated with MMF (dose range, 500 to 2,000 mg) for a mean of 8 months. Six patients experienced a halving of proteinuria, which occurred after a mean duration of 6 months of therapy. Partial remissions occurred in 2 patients. There were no significant changes in mean values for serum creatinine, serum albumin, or proteinuria. Mean cholesterol levels were significantly less. Side effects of MMF were infrequent and generally mild. In summary, MMF appears to reduce proteinuria in some patients with idiopathic MN previously resistant to steroids, cytotoxic agents, or cyclosporine. Further trials with this agent are warranted.

Does immunosuppression with prednisolone and azathioprine alter the progression of idiopathic membranous nephropathy?

The role of immunosuppressive drugs in the treatment of idiopathic membranous nephropathy (IMN) remains controversial. The effect of treatment with prednisolone and azathioprine in patients with nephrotic-range proteinuria and biopsy-proven IMN from a single center (Sheffield Kidney Institute, Sheffield, UK) is described. In this retrospective study, 58 patients with IMN and nephrotic-range proteinuria were followed up for 4 years. Thirty-eight patients were treated with prednisolone (1 mg/kg body weight/d) and azathioprine (2 mg/kg body weight/d) orally for a median period of 26 months (range, 6 to 48 months). Twenty patients received no specific treatment for IMN and served as a control group. Clinical, biochemical, and histopathologic features at presentation were similar between the groups. Renal function (RF), measured by serum creatinine (Scr) level, deteriorated in both treated and control groups during the follow-up period. The median initial and final Scr levels (at the end of follow-up) in the treated group were 1.6 and 2. 1 mg/dL, respectively, and in the control group were 1.3 and 1.7 m/dL, respectively (P = not significant). Neither the rate of RF decline (measured by the slope of reciprocal of Scr against time) nor the proportion of patients with deteriorating RF differed significantly between the groups (37%, treated group; 30%, control group). A significant reduction in proteinuria was observed in both groups (P < 0.01, either group). Also, the rate of remission of nephrotic-range proteinuria was not significantly different between groups (55%, treated group; 65%, control group). The only prognostic factor that correlated with RF outcome (expressed by final Scr level) in a given patient was the mean proteinuria during follow-up in either group (r = 0.493; P < 0.01, treated group; r = 0.651; P < 0.01, control group). Adverse effects of immunosuppressive treatment were observed in nine patients (24%). These were serious in four patients (10%) and included squamous cell carcinoma (two patients), bacterial meningitis (one patient), and septicemia (one patient). In conclusion, treatment with prednisolone and azathioprine for patients with IMN did not show significant beneficial effects on the progression of disease. Furthermore, this treatment was associated with frequent and serious adverse effects.

Prognosis after a complete remission in adult patients with idiopathic membranous nephropathy

This review of the long-term outcome after a complete remission of proteinuria includes 82 adult patients with biopsy-proven idiopathic membranous glomerulonephritis (IMGN), who represented 25% of the total cases (82 of 323 cases) of IMGN in our registry. Complete remission was defined as at least two consecutive follow-up evaluations showing proteinuria of 0.3 g/d or less of protein. Before remission, 70% of the patients had nephrotic-range proteinuria (61% at presentation, 9% during follow-up), and 30% were always subnephrotic (protein level < 3.5 g/d). Mean total observation time was 101 +/- 56 months, with a postremission period of 69 +/- 60 months. Seventy-one percent of the patients remained in remission and 29% relapsed. In the relapse group, 46% relapsed to nephrotic-range proteinuria and 54% relapsed to subnephrotic levels. The plasma creatinine level remained stable in 86% of the patients (71 of 82 patients) but became or remained elevated despite a period of complete remission in the remaining 14% (8 of 82 patients). No patient went on to end-stage renal disease. Seventy-seven percent of the patients had no specific treatment within 6 months of remission, whereas 23% had steroid therapy alone or in combination with an immunosuppressive agent. In a multivariate analysis, the factors that favored both remission and its durability were persistent lower levels of proteinuria and female sex. Complete remission indicates an excellent long-term prognosis in patients with IMGN, but relapses are common and, in a small percentage, chronic renal insufficiency occurs. Thus, our data suggest that even this group of patients should be monitored on a regular basis.

Management of idiopathic membranous nephropathy: evidence-based recommendations

Membranous nephropathy is a frequent cause of nephrotic syndrome in adults, and in one third of these patients, it leads to end-stage renal disease. Based on an extensive critical review of the literature, the following recommendations are offered. Oral high-dose corticosteroids are ineffective in producing either a sustained remission of nephrotic syndrome or in preserving renal function in patients with membranous nephropathy, and should not be used as the sole therapy (grade A recommendation). The use of azathioprine is not associated with any significant benefits, so its use is not justified (grade C). The alkylating agents cyclophosphamide and chlorambucil are both effective in the management of membranous nephropathy. Because of growing concern about long-term toxicity, especially with cyclophosphamide, these drugs should be reserved for patients who exhibit clinical features, such as severe or prolonged nephrosis, renal insufficiency, or hypertension, that predict a high likelihood of progression to end-stage renal disease. Chlorambucil in conjunction with oral steroids is the drug of first choice (grade A). Cyclophosphamide and oral steroids are alternatives (grade B). Cyclosporine may, in the future, become the agent of choice for membranous nephropathy. Currently, it is recommended (grade B) that cyclosporine use be considered in patients at high risk for progression in membranous nephropathy or if alkylating agents are contraindicated or ineffective.

Effects of glucocorticoid therapy on urine protein-to-creatinine ratios and renal morphology in dogs

Glomerulonephritis has been associated with exogenous glucocorticoid administration and spontaneous hyperadrenocorticism in the dog. The purpose of this study was to determine the effects of long-term glucocorticoid therapy on urine protein:creatinine ratios (UP/Cs) and renal morphology. Nine young-adult male dogs were determined to be healthy and have normal renal function as assessed by physical examination, CBC, serum biochemistry analysis, Knott's test for Dirofilaria immitis, urinalysis, urine culture, urine protein electrophoresis, endogenous creatinine clearance, 24-hour urinary protein excretion, and UP/C. Prednisone was administered to each dog at a dosage of 2.2 mg/kg PO bid for 42 days. Urinalysis and UP/C were performed on days 0, 7, 14, 21, 28, and 42 of treatment. Mean UP/C on day 0 was 0.29 +/- 0.10. Mean UP/C increased progressively to a maximum of 1.27 +/- 1.02 on day 28. Mean UP/C on day 42 decreased slightly (0.92 +/- 0.56) but remained significantly increased above baseline. The most consistent renal light microscopic finding on necropsy examination was generalized hypercellular glomerular tufts, suggestive of mesangial cell proliferation. Four dogs also had occasional adhesions of glomerular tufts to Bowman's capsule, accompanied by thickening of the capsule. Direct immunofluorescence for immunoglobulin deposition was negative in all dogs. Electron microscopy, evaluated in 7 dogs, was characterized by occasional mild segmental thickening of basement membranes, fusion of visceral cell foot processes, and glomerular adhesions. The results of this study indicate that long-term administration of glucocorticoids results in significant proteinuria and glomerular changes in the dog.

Diagnosis and management of glomerular diseases

Glomerular diseases are a diagnostic challenge. Early recognition and timely institution of appropriate treatment are critical to optimum outcome in many patients, especially those with rapidly progressive glomerulonephritis. The clinical presentations and laboratory data provide adequate presumptive diagnoses in some patients; however, renal biopsy evaluation is often required for a definitive diagnosis.

Validation of a predictive model of idiopathic membranous nephropathy: its clinical and research implications

Although a number of factors have consistently correlated with progression to chronic renal insufficiency (CRI) in idiopathic membranous glomerulonephropathy (IMGN), they appear late, are not quantitative in nature and have not been validated. We have determined that the highest sustained six-month period of proteinuria is an important predictor of progression. Using multiple logistic modelling, the only additional prognostic variables of importance in 184 Canadian patients were the initial creatinine clearance and the rate of change in function over this six-month interval. Independent data from Italy (101 patients) and Finland (78 patients) were obtained for comparison. Sensitivity, specificity, negative and positive predictive values and overall accuracy, as well as Pearson's goodness-of-fit and Harrell's "C" statistic were used to assess the fits of the model. Accuracy of prediction was > or = 85% in all three countries. Pearson's Chi-square goodness-of-fit showed good agreement across the spectrum and Harrell's "C" statistic was > or = 90%. Therefore, a predictive, semiquantitative algorithm in IMGN has been validated. Its relevance in patient management and in clinical trials is illustrated.

BIAS IN LINEAR MODEL POWER AND SAMPLE SIZE DUE TO ESTIMATING VARIANCE

Planning a study using the General Linear Univariate Model often involves sample size calculation based on a variance estimated in an earlier study. Noncentrality, power, and sample size inherit the randomness. Additional complexity arises if the estimate has been censored. Left censoring occurs when only significant tests lead to a power calculation, while right censoring occurs when only non-significant tests lead to a power calculation. We provide simple expressions for straightforward computation of the distribution function, moments, and quantiles of the censored variance estimate, estimated noncentrality, power, and sample size. We also provide convenient approximations and evaluate their accuracy. The results allow demonstrating that ignoring right censoring falsely widens confidence intervals for noncentrality and power, while ignoring left censoring falsely narrows the confidence intervals. The new results allow assessing and avoiding the potentially substantial bias that censoring may create.

Pharmacology of immunosuppressive medications used in renal diseases and transplantation

As understanding of the molecular basis for the immune response has expanded rapidly, so have the possibilities for designing therapeutic interventions that are more effective, more specific, and safer than current treatment options. The promise of therapeutic advances in the future is based on the rapidly expanding insights into the pathogenesis of abnormal immunologic reactions. Nowhere is the understanding of molecular mechanisms, pathophysiology, and targeted therapy more relevant than in the field of renal transplantation, which makes up much of the clinical database for the use of immunosuppressive therapy for renal disease. Despite the recent advances in basic immunology, clinical validation of new agents and approaches is lacking for most drugs at present. This review will focus in the pharmacology of agents used in the therapy of immunologic renal disease and in renal transplantation. It should be recognized that clinical pharmacology and experience with newer agents is limited, and potential utility is based largely on experimental data.

Urinary C5b-9 excretion and clinical course in idiopathic human membranous nephropathy

Recent reports suggested that the presence of terminal complement complex (C5b-9) in urine from patients with idiopathic membranous nephropathy (IMN) may indicate on-going immunological damage. This report documents the relationship between C5b-9 excretion and clinical outcome in 35 adult patients with biopsy-proven IMN and progressively declining renal function. There were two groups of patients. Group I received one of three treatment regimens: prednisolone alone, prednisolone and chlorambucil, or prednisolone and cyclophosphamide (N = 22). Group II received no immunosuppressive therapy (N = 17). Three of the 18 patients receiving immunosuppressive drugs had more than one treatment regimen as they experienced a clinical relapse during the study period; hence 22 treatments were available for analysis. Urine samples were collected regularly and urinary C5b-9 (uC5b-9) was determined by ELISA. Both groups were similar with respect to age, sex distribution, and the duration of follow-up. An improvement in proteinuria and creatinine clearance was noted in the immunosuppressed group. Thirty-five patients were excreting C5b-9 initially (18 from group I and 17 from group II); 17 patients continued to excrete C5b-9 at the end of the observation period. These 17 patients had a significantly worse clinical outcome when compared to the 18 patients whose C5b-9 excretion became negative, either spontaneously or with treatment (P < 0.005). These results indicate that continuing C5b-9 excretion is correlated with a poor clinical outcome. They also suggest that uC5b-9 is a dynamic marker of ongoing immunological injury, and therefore may be useful in the initial assessment and monitoring of patients with IMN and in identifying patients who may derive benefit from immunosuppressive therapy.

A controlled trial of cyclosporine in patients with progressive membranous nephropathy. Canadian Glomerulonephritis Study Group

A controlled trial of cyclosporine in patients diagnosed with progressive membranous nephropathy (MGN) was carried out to determine whether cyclosporine (D) would be more effective than placebo (P) in reducing the rate of deterioration in renal function. Patients (N = 64) with MGN were placed on a restricted protein diet (< or = 0.9 g/kg) and followed closely for 12 months (Part 1). Patients at high risk of progression based on an absolute loss in creatinine clearance (CCr) of > or = 8 ml/min and persistent nephrotic range proteinuria (Pr) were selected and randomly assigned to either (D) (N = 9) or (P) (N = 8) for 12 months (Part 2). No differences in the two groups were noted at entry. After 12 months, the improvement in CCr slope in ml/min/month was significantly greater in the D patients (D + 2.1 vs. P + 0.5, mean difference 1.6; 95% CI 0.3 to 3.0, P < 0.02). This improvement was maintained in six of eight D (75%) over a mean follow-up period of 21 months. Daily Pr also improved with D (by month 3, D - 4.5 g/day vs. P + 0.7 g/day, P = 0.02) and was sustained in six of eight (75%) D patients. When Pr was expressed as a function of their concurrent CCr, the D versus P patients' time to halving was faster (P = 0.02) and absolute number higher (4/9 D vs 0/8 P). In the D group a trend towards worse hypertension and an increase in the number of transient rises in serum creatinine were noted.(ABSTRACT TRUNCATED AT 250 WORDS)

Computing Confidence Bounds for Power and Sample Size of the General Linear Univariate Model

The power of a test, the probability of rejecting the null hypothesis in favor of an alternative, may be computed using estimates of one or more distributional parameters. Statisticians frequently fix mean values and calculate power or sample size using a variance estimate from an existing study. Hence computed power becomes a random variable for a fixed sample size. Likewise, the sample size necessary to achieve a fixed power varies randomly. Standard statistical practice requires reporting uncertainty associated with such point estimates. Previous authors studied an asymptotically unbiased method of obtaining confidence intervals for noncentrality and power of the general linear univariate model in this setting. We provide exact confidence intervals for noncentrality, power, and sample size. Such confidence intervals, particularly one-sided intervals, help in planning a future study and in evaluating existing studies.

Fundamental concepts and immunosuppressive treatment in the various forms of glomerulonephritis

Immunosuppressive treatment in glomerulonephritis (GN) is still controversial. Most of the secondary forms of glomerulonephritis have the histologic features of one of the primary types of glomerulonephritis. Eight histologic expressions of primary glomerulonephritis can be distinguished and ordered in terms of severity of symptoms and prognosis: endocapillary GN, minimal change GN, mesangioproliferative GN, membranous GN, focal-sclerosing GN, membranoproliferative GN, focal-necrotizing GN, and rapidly progressive GN. Agreement exists only to the extent that immunosuppression is not required in endocapillary glomerulonephritis, although it is recommended in the other extreme of rapidly progressive GN. Primarily, an indication for immunosuppression is given by the severity of symptoms with a urinary protein excretion > 3.5 g per day and/or serum creatinine > 150 mumol per liter. As for anti-GBM, the type of glomerulonephritis is more important than the severity of symptoms in guiding therapy, whereas for IgA nephropathy it is controversial whether the prospective prognosis of even inexorably deteriorating renal function justifies immunosuppression. Renal biopsy is required to identify the type of glomerulonephritis so as to establish the specific immunosuppressive concept with different intensity and duration of treatment. Immunosuppression can reduce urinary protein excretion and improve deterioration of renal function; however, the proportion of patients responding varies with and depends on the different forms of GN.