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

Efficacy of a second course of immunosuppressive therapy in patients with membranous nephropathy and persistent or relapsing disease activity

BACKGROUND

A single course of immunosuppressive treatment improves renal survival in patients with idiopathic membranous nephropathy (iMN) and renal insufficiency. However, not all patients respond and relapses occur within 5 years in 30% of patients. It is unknown if a second course of immunosuppressive therapy is effective in such patients.

METHODS

We have prospectively studied and evaluated the clinical course in 15 patients (14 male, one female; age: 52+/-12 years) with iMN who have received a repeated course of immunosuppressive therapy because of deteriorating renal function associated with relapsing or persistent nephrotic syndrome.

RESULTS

The first course of immunosuppression was started 8 months (range: 0-143 months) after renal biopsy and consisted of chlorambucil (n = 8) or cyclophosphamide (n = 7); the second course consisted of cyclophosphamide in all patients. The interval between the first and second course was 40 months (range: 7-112 months). Total follow-up was 110 months (range: 46-289 months). Renal function and proteinuria improved at least temporarily in all patients after the second course. During follow-up, an additional course of therapy was given in four patients. Status at the end of follow-up was complete remission (n = 2), partial remission (n = 8), persistent proteinuria (n = 3), end-stage renal disease (n = 1) and death (n = 1, due to cardiovascular disease while nephrotic). Renal survival was 86% at 5 and 10 years of follow-up. The repeated courses of immunosuppression have resulted in a gain of dialysis-free survival time of > or =93 months (range: 43-192 months).

CONCLUSIONS

Our results indicate that patients with iMN who do not respond well or relapse after a first course of immunosuppressive therapy and have renal insufficiency should be offered a second course of immunosuppression. Such a strategy maintains renal function in the majority of patients.

Mycophenolate mofetil and cyclosporine therapy in membranous nephropathy

Idiopathic membranous nephropathy (IMN) remains one of the most common causes of the nephrotic syndrome (NS) in adults. Although the natural history is extremely variable, approximately two thirds of the patients will have persistent high-grade proteinuria and/or develop renal failure over a decade of observation. On the other hand, the remaining third of patients will remit spontaneously and potentially toxic therapy should be avoided in this group. Our capacity to predict which patient will progress at an early stage of the disease has improved substantially in the past 10 years. We present the data from studies of cyclosporine (CSA) and mycophenolate mofetil (MMF) treatment of IMN with their level of evidence in support of efficacy. In addition, based on data related to predicting prognosis, we assign a risk for progression category to the trial patients at entry into these studies. The data are presented in this format so the reader will be able to better discern the risk benefit of treatment within each category and the rationale for our subsequent grade of recommendation for the use of these agents in IMN. CSA has been shown in randomized controlled trials in both the medium and high risk of progression categories of IMN patients to improve proteinuria and preserve renal function at least in the short term in up to two thirds of patients. Other studies suggest prolonged therapy beyond 6 months to 1 year may reduce the high relapse rate after CSA treatment supporting more long-term, continuous, or combination therapy in IMN treatment. The data in favor of MMF treatment of this disease is much weaker and are derived from pilot studies. Only one report applied MMF specifically to IMN patients. In these medium to high risk of progression patients, approximately one-half had a 50% reduction in their baseline proteinuria without a significant alteration in their serum creatinine level. MMF's role as a single agent or as adjunctive therapy in the treatment of IMN needs more rigorous evaluation.

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.

Advances in the treatment of lupus nephritis

Systemic lupus erythematosus (SLE) is an autoimmune disease that leads to the formation and deposition of immune complexes throughout the body, which are pathogenic for the disease. Different forms of glomerulonephritis can occur in patients with SLE and can contribute significantly to the associated morbidity and, ultimately, mortality from the disease. Over the past two decades, there have been significant strides in our understanding of the disease and in treatments that attempt to control the formation and deposition of anti-DNA auto-antibodies and immune complexes, as well as the subsequent inflammatory cascade mediated through various cellular and humoral pathways leading to progressive renal damage and end-stage renal disease. In this chapter, we review the current understanding of the pathogenesis and treatment of lupus nephritis in its various stages and discuss the experimental and human data regarding some of the potential newer forms of therapy. We discuss data regarding the use of steroids, azathioprine, cyclophosphamide, cyclosporine A, mycophenolate mofetil, gammaglobulin, plasmapheresis, LJP 394, flaxseed oil, bindarit, anti-CD40 ligand, and CTLA4Ig.

Cyclosporine in patients with steroid-resistant membranous nephropathy: a randomized trial

BACKGROUND

A clinical trial of cyclosporine in patients with steroid-resistant membranous nephropathy (MGN) was conducted. Although MGN remains the most common cause of adult-onset nephrotic syndrome, its management is still controversial. Cyclosporine has been shown to be effective in cases of progressive MGN, but it has not been used in controlled studies at an early stage of the disease.

METHODS

We conducted a randomized trial in 51 biopsy-proven idiopathic MGN patients with nephrotic-range proteinuria comparing 26 weeks of cyclosporine treatment plus low-dose prednisone to placebo plus prednisone. All patients were followed for an average of 78 weeks, and the short- and long-term effects on renal function were assessed.

RESULTS

Seventy-five percent of the treatment group versus 22% of the control group (P < 0.001) had a partial or complete remission of their proteinuria by 26 weeks. Relapse occurred in 43% (N = 9) of the cyclosporine remission group and 40% (N = 2) of the placebo group by week 52. The fraction of the total population in remission then remained almost unchanged and significant different between the groups until the end of the study (cyclosporine 39%, placebo 13%, P = 0.007). Renal function was unchanged and equal in the two groups over the test medication period. In the subsequent follow-up, renal insufficiency, defined as doubling of baseline creatinine, was seen in two patients in each group, but remained equal and stable in all of the other patients.

CONCLUSION

This study suggests that cyclosporine is an effective therapeutic agent in the treatment of steroid-resistant cases of MGN. Although a high relapse does occur, 39% of the treated patients remained in remission and were subnephrotic for at least one-year post-treatment, with no adverse effect on filtration function.

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.

Cyclosporine for lupus membranous nephritis: experience with ten patients and review of the literature

OBJECTIVES

The treatment of lupus membranous nephritis (LMN), a lupus subset that carries a high morbidity, is unsatisfactory. We report our experience in treating LMN with the immunosuppressive drug cyclosporine (CYS).

METHODS

We treated 10 patients with systemic lupus erythematosus fulfilling ACR criteria with CYS for at least 12 months and followed renal function, serologic activity and SLEDAI scores.

PATIENT CHARACTERISTICS

8 females, 2 males, 50% Caucasian, mean age 37.3 y (range 22-48), disease duration 108.7 months (range 16-216), nephritis duration 35.5 months (range 12-59), date of biopsy to date of starting treatment 10.7 months (range 0-90). The patients were started on CYS with a mean dose of 3.8 mg/kg (range 2.2-6) and followed for a mean duration of 24.8 months (range 12-59). A Medline search identified all patients with lupus who were given CYS or had LMN in articles from 1966-1999.

RESULTS

Proteinuria improved from a baseline mean of 5,588mg/24h (range 2,712-11,055) to 1,404 mg/24 h (range < 150-2,652). Serum albumin increased from a baseline mean of 2.8 g/100 ml (range 1.31-3.8) to a mean of 3.9 g/100 ml (range 3-4.5) at last follow-up. There was no significant change in lupus activity as measured by SLEDAI. Nephrotoxicity was common as evidenced by an increase in serum creatinine but it returned to baseline with adjustment of the dose of CYS (20% decrease in the dose of CYS for a 20% increase in serum creatinine). More antihypertensive medications were required to control the blood pressure in these ten patients at the end of the study compared to the onset (total number= 13 versus 6).

CONCLUSION

Proteinuria and serum albumin improved in all patients on CYS. A literature review is consistent with this. Controlled studies of the use of CYS for membranous lupus nephritis would be useful.

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.

Decreased urinary excretion of vascular endothelial growth factor in idiopathic membranous glomerulonephritis

BACKGROUND

Membranous glomerulonephritis (MGN) has, for unknown reasons, an unpredictable and highly variable clinical course. Vascular endothelial growth factor (VEGF) enhances endothelial cell proliferation, angiogenesis, microvascular permeability, and monocyte chemotaxis, and it activates proteinases. In normal kidneys, it is predominantly expressed by glomerular podocytes, where its physiological function and role in development of renal diseases are obscure. This study was designed to evaluate the urinary excretion of VEGF in MGN compared with several other glomerular disease and to asses its relationships to the clinical activity of MGN.

METHODS

Urinary VEGF was studied during renal biopsy using a sandwich enzyme immunoassay from 30 patients with idiopathic MGN, 8 with minimal change glomerulonephritis, 10 with focal segmental glomerulosclerosis (FSGS), 8 with necrotizing glomerulonephritis associated with systemic vasculitis, and 12 with diabetic nephropathy. In addition, 33 healthy controls were examined. Fifteen patients with MGN were re-evaluated 12 months later, and the evolution of proteinuria was compared with changes in urinary VEGF excretion.

RESULTS

In healthy control subjects, urinary VEGF excretion was 68 +/- 10 (95% CI, 49 to 88) ng/mmol creatinine (UCr). In MGN, the excretion was decreased to 16 +/- 3 (CI, 10 to 23) ng/mmol crea (P < 0.0001, ANOVA), whereas in minimal change glomerulonephritis and diabetic nephropathy, it was unchanged [55 +/- 14 (CI, 24 to 86) and 101 +/- 25 (CI, 45 to 156) ng/mmol UCr, respectively, P = NS]. In vasculitis and FSGS patients, the excretion was higher than normal [184 +/- 68 (CI, 24 to 344), P = 0.01, and 160 +/- 29 (CI 95 to 226), P = 0.002 ng/mmol UCr, respectively]. The excretion did not correlate with serum VEGF, renal function, or proteinuria. In the follow-up of 15 patients, improving MGN (decreasing proteinuria) was associated with increasing VEGF excretion, while persistent disease (no change or increase of proteinuria) was associated with constantly low urinary VEGF excretion. The change in urinary protein excretion over one year correlated inversely with the change in urinary VEGF (r = -0.57, P = 0.026).

CONCLUSIONS

MGN is associated with decreased urinary VEGF compared with normal subjects, which is in contrast with other proteinuric diseases. Moreover, decreasing clinical activity (proteinuria) is accompanied by increasing VEGF excretion. Urinary VEGF may serve as an indicator of activity of MGN.

Cyclosporin treatment of glomerular diseases

Cyclosporin is a potent immunosuppressive agent that has become the first line therapy in organ transplantation. Its efficacy has led to its use in a variety of immune-mediated glomerular diseases. A selection of controlled and uncontrolled trials has studied the effects of cyclosporin in patients with minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN), IgA nephropathy, membranoproliferative glomerulonephritis (MPGN) and lupus nephritis. We review the recent literature and suggest recommendations for using cyclosporin in these diseases, based on this evidence and our experience.

A randomized trial of cyclosporine in patients with steroid-resistant focal segmental glomerulosclerosis. North America Nephrotic Syndrome Study Group

A randomized trial of cyclosporine in patients with steroid-resistant focal segmental glomerulosclerosis.

BACKGROUND

A clinical trial of cyclosporine in patients with steroid-resistant focal segmental glomerulosclerosis (FSGS) was conducted. Despite the fact that it is the most common primary glomerulonephritis to progress to renal failure, treatment trials have been very limited.

METHODS

We conducted a randomized controlled trial in 49 cases of steroid-resistant FSGS comparing 26 weeks of cyclosporine treatment plus low-dose prednisone to placebo plus prednisone. All patients were followed for an average of 200 weeks, and the short- and long-term effects on renal function were assessed.

RESULTS

Seventy percent of the treatment group versus 4% of the placebo group (P < 0. 001) had a partial or complete remission of their proteinuria by 26 weeks. Relapse occurred in 40% of the remitters by 52 weeks and 60% by week 78, but the remainder stayed in remission to the end of the observation period. Renal function was better preserved in the cyclosporine group. There was a decrease of 50% in baseline creatinine clearance in 25% of the treated group compared with 52% of controls (P < 0.05). This was a reduction in risk of 70% (95% CI, 9 to 93) independent of other baseline demographic and laboratory variables.

CONCLUSIONS

These results suggest that cyclosporine is an effective therapeutic agent in the treatment of steroid-resistant cases of FSGS. Although a high relapse rate does occur, a long-term decrease in proteinuria and preservation of filtration function were observed in a significant proportion of treated patients.

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.

Prediction in idiopathic membranous nephropathy

BACKGROUND

Results of the prognosis of idiopathic membranous nephropathy are conflictive and prevent an effective risk stratification. These conflicts are explained in part by insufficient consideration of methodological principles for prognostic research. This cohort study is aimed at identifying clinical predictors for risk stratification while paying particular attention to methodology.

METHODS

We studied 120 patients with idiopathic membranous nephropathy. Baseline data were extracted at the time of diagnostic renal biopsy, and patients were followed prospectively. Predictors were identified for the end points end-stage renal failure (ESRF) and ESRF or death.

RESULTS

From the 120 patients followed for a median of five years (1 to 24 years), 19% developed end-stage renal failure or deterioration of renal function. Proteinuria of more than 3.5 g/day persisted in 34%, and 47% were in complete or partial remission. The Kaplan-Meier estimated probability of renal survival was 91 +/- 3% at five years and 75 +/- 6% at ten years. The predictors for the primary outcome, ESRF, identified in a Cox proportional hazards model, were histological stage (Ehrenreich-Churg) III-IV (hazard ratio 5.3, CI 1.9 to 15.0, P = 0.002) and nephrotic syndrome (hazard ratio 7.9, CI 1.1 to 61.5, P = 0.04); the predictors for the secondary outcome, ESRF or patient death, were histological stage III-IV (hazard ratio 2.8, CI 1.3 to 6.0, P = 0.008), nephrotic syndrome (hazard ratio 3.0, CI 1.1 to 8.0, P = 0.003) and comorbidity (hazard ratio 2.8, CI 1.3 to 5.9, P = 0.007). Nephrotic syndrome and histological stage III-IV allowed the demarcation of the high-risk group from the remaining patients (P < 0.0001).

CONCLUSION

Histological stage, nephrotic syndrome, and comorbidity predict end-stage renal failure or death in idiopathic membranous nephropathy. Identification of the high-risk group at the time of diagnostic renal biopsy will permit appropriate treatment to be targeted to the patients who might benefit the most from the therapy in future clinical trials.

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.

Role of interferon-alpha in the treatment of primary glomerulonephritis

Interferon-alpha (IFN-alpha) is a naturally occurring cytokine. It was the first cytokine used with clinical benefit in the treatment of viral hepatitis and malignancies. Patients with viral hepatitis B or C may have complications with glomerulonephritis (GN). Improvement in proteinuria with or without clearing of viral markers after IFN-alpha therapy has been reported. This encouraged us to offer IFN-alpha therapy to four patients with GN. These patients refused treatment with steroids and/or cyclophosphamide because of concerns about side effects. One patient with membranous GN and two patients with mesangial GN (MesGN) had a remission of nephrotic syndrome. In one patient with type II diabetes and MesGN, renal insufficiency and proteinuria did not subside; however, renal function remained stable. The mechanism of action of IFN-alpha is discussed, with its possible role in the treatment of primary GN.

Cyclosporine treatment of glomerular diseases

Cyclosporine-A is primary therapy for organ transplantation. Its immunosuppressive effect might suggest a therapeutic role in autoimmune diseases, including several idiopathic and secondary glomerular conditions. Various forms of idiopathic nephrotic syndrome, including focal segmental glomerulosclerosis (FSGS), minimal change disease (MCD), and membranous nephropathy (MN), may respond well to cyclosporine in selected patients. However, frequent relapse limits its use to those who have failed to respond to, or were intolerant of, steroids or cytotoxics. Cyclosporine's efficacy in other glomerulopathies, such as IgA nephropathy (IgAN) and membranoproliferative glomerulonephritis (MPGN) remains poorly studied and, given the risk of nephrotoxicity, cannot be recommended for treatment of these entities until further data are available. Cyclosporine demonstrates some efficacy in treating proliferative lupus nephritis and, based on pilot study data, membranous lupus as well. Again, given relapse rates and potential nephrotoxicity, it should be used only in combination with azathioprine and steroids, assuming cytotoxic therapy has failed. Finally, cyclosporine toxicity is briefly reviewed.

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.

Cyclosporine therapy affects aminotransferase activity but not hepatitis C virus RNA levels in chronic hepatitis C

Interferon (IFN) therapy is of proven efficacy in chronic hepatitis C, but it is not universally effective and is often limited by side effects. Cyclosporine A (CsA) is a potent immunosuppressant widely used in organ transplantation. We conducted a pilot study to determine whether CsA therapy could affect aminotransferase activity and hepatitis C virus RNA levels in patients with chronic hepatitis C. Cyclosporine A was administered to 10 patients (mean age of 59 years; male:female = 9:1) who did not respond to IFN therapy previously and who had elevated serum alanine aminotransferase (ALT) values for at least 6 months. All patients were positive for HCV-RNA by RT-PCR with genotype 1b. Their mean duration of hepatitis was 15 years. Oral CsA was given for 3 months in a dose that was increased at 1 month intervals from 1.5-2.0 to 2.0-3.0 and 3.0-4.0 mg/kg per day. All patients completed the treatment schedule, although two patients developed mild non-symptomatic hypertension. Serum ALT levels gradually decreased in all but one patient. The mean percentage decrease was 59.5% at the end of therapy (from 153 +/- 82 to 62 +/- 48 IU/L; P < 0.02). The ALT levels fell to the normal range in five patients, although once therapy was discontinued the enzyme levels tended to return to pretreatment levels. Serum aspartate aminotransferase and g-glutamyl transpeptidase levels similarly decreased. The serum HCV-RNA titre, determined by competitive RT-PCR, did not change in any patient throughout the study period. There were no appreciable alterations in other laboratory tests, such as serum creatinine levels and lymphocyte subsets, except for an increase in serum alkaline phosphatase levels. These findings suggest that CsA, even in a relatively low dose, reduces serum aminotransferase levels without serious side effects in patients with chronic hepatitis C, although an antiviral effect was not noted.

The primary glomerulopathies

Disorders of glomerular structure and function are encountered frequently in clinical medicine. Many arise as part of a well-defined multisystem or multi-organ disease process, while in others the clinical and laboratory manifestations are consequent to the sole or predominant involvement of glomeruli. The latter are known as the primary glomerulopathies. These disorders can evoke a variety of clinical syndromes, including acute glomerulonephritis, rapidly progressive glomerulo-nephritis, nephrotic syndrome, "symptomless" hematuria and/or proteinuria, and chronic glomerulonephritis. The identification of underlying morphology, through the application of renal biopsy techniques, can provide useful information for both prognosis and treatment. Pathogenic mechanisms involved in the primary glomerulopathies are varied, but immunologic perturbations underlie many disease entities. This article describes the clinical features, pathology, natural history, and treatment of the main categories of primary glomerulonephritis, with emphasis on recent developments and practical aspects of diagnosis and management.