Cyclosporin A treatment in children with minimal change nephrotic syndrome and focal segmental glomerulosclerosis

Efficacy and Safety of Immunosuppressive Therapy in Primary Focal Segmental Glomerulosclerosis: A Systematic Review and Meta-analysis

Rationale & Objective

Focal segmental glomerulosclerosis (FSGS) is a rare condition that can lead to kidney function decline and chronic kidney failure. Immunosuppressants are used to treat primary FSGS. However, their efficacy and safety in FSGS are not clearly established. We assessed current knowledge on clinical effectiveness and safety of immunosuppressants for primary FSGS.

Study Design

Systematic review of randomized controlled trials, interventional nonrandomized controlled trials, observational studies, retrospective studies, and registries.

Setting & Participants

Patients with primary and genetic FSGS.

Selection Criteria for Studies

Medline, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for English-language, primary-FSGS studies from inception to 2019. Clinical outcomes were changes from baseline in proteinuria, kidney function, and kidney survival.

Data Extraction

2 investigators independently screened studies and extracted data.

Analytical Approach

Study results were summarized using random-effects models either as ratios of means between follow-up and baseline measurements or as HRs.

Results

We included 98 articles. Substantial heterogeneity was observed in patient baseline characteristics and study designs. Most studies assessed treatment with corticosteroids alone or combined with other drugs, mainly immunosuppressants. Patients treated with immunosuppressants showed reduced proteinuria (14 studies; ratio of means, 0.36; 95% CI, 0.20-0.47), decreased creatinine clearance (mean difference, −25.03; 95% CI, −59.33 to −9.27) and (significantly) lower estimated glomerular filtration rates (mean difference, −7.61 mL/min/1.73 m²; 95% CI, −14.98 to 0.25 mL/min/1.73 m²). Immunosuppressant therapy had an uncertain effect on reducing the chronic kidney failure risk. Hypertension and infections were the most commonly reported adverse events.

Limitations

Heterogeneity in study designs, patient populations, and treatment regimens; no access to individual patient–level data.

Conclusions

This systematic review supports proteinuria reduction with immunosuppressant therapy in primary FSGS over varying follow-up periods. The effects of immunosuppressants on kidney survival remain uncertain. This review underscores the need for better-designed and adequately controlled studies to assess immunosuppressant therapy in patients with primary FSGS.

Impact of cyclosporin on podocyte ZO-1 expression in puromycin aminonucleoside nephrosis rats

Puromycin aminonucleoside (PAN)-induced nephrosis is a well-described model of human idiopathic nephrotic syndrome, but the mechanism of PAN's effect is not completely understood. To investigate whether proteinuria in the PAN model is associated with an alteration of zonula occludens-1 (ZO-1) expression within the glomeruli, and whether cyclosporin A (CsA) has an effect on proteinuria and ZO-1 expression in this model, eighteen Sprague Dawley (SD) rats were assigned into three groups. Twelve rats received a single intraperitoneal injection of PAN (15 mg/100 g). The other six rats received an equal volume of saline (normal control group; control). CsA solution was administered intraperitoneally once a day for 20 days after the PAN injection (n=6, PAN+CsA). The remaining six rats received PAN, but they didn't receive CsA (n=6, PAN). Compared to control rats (35.1+/-5.4 mg/day), the 24-hour urinary protein excretion on day 18 was significantly higher in the PAN rats (1021.9+/-128.9 mg/day, p<0.01), and the CsA treatment partly reversed the increase in proteinuria in the PAN rats (556.4+/-102.3 mg/day, p<0.05). Glomerular ZO-1 protein expressions were significantly increased in the PAN rats as compared to the control group on day 20 (176%, p<0.01). CsA treatment for 20 days in the PAN rats inhibited the increase in ZO-1 protein expression by 71.1% (p<0.05). CsA treatment significantly diminished the glomerular ZO-1 expression in the PAN rats as assessed by immunohistochemistry. CsA treatment significantly reduced proteinuria and the diminished glomerular ZO-1 expression in a PAN nephrosis rat model. These findings suggest the potential role of the slit diaphragm associated proteins in the development of the nephrotic syndrome, and CsA decreased the proteinuria probably by a direct action on the expression of these proteins in podocytes. Further investigations are needed to clarify the role of slit diaphragm associated proteins in the development of PAN nephrosis.

Cyclosporine A and chlorambucil in the treatment of idiopathic focal segmental glomerulosclerosis

BACKGROUND

The therapy of nephrotic syndrome in focal segmental glomerulosclerosis (FSGS) is still a matter of controversy.

METHODS

We performed a prospective randomized study of the treatment of nephrotic syndrome due to FSGS. We compared 2 specific treatment protocols to assess the effect of treatment on proteinuria and renal function. Fifty-seven patients were randomly assigned to 2 groups: group 1 (n = 34) received steroids and cyclosporine, and group 2 (n = 23) received steroids and chlorambucil for 6 months. When treatment was refractory to chlorambucil, the patients in this group were treated with cyclosporine. Creatinine, blood urea nitrogen, proteinuria, lipids, and arterial hypertension were monitored at regular intervals.

RESULTS

Patients showed a mean serum creatinine of 1.5 +/- 0.2 mg/dL (132.6 +/- 17.7 micromol/L) and proteinuria of 4.8 +/- 2.8 g/24 h with no differences between the groups. At the end of the chlorambucil therapy, patients in group 2 had creatinine levels of 1.8 +/- 0.6 mg/dL (159.1 +/- 53 micromol/L) and proteinuria levels of 3.4 +/- 1 g/24 h. All patients in this group were given cyclosporine. After 4 years the mean creatinine level in group 1 was 1.7 +/- 0.4 mg/dL (150.3 +/- 35.4 micromol/L) and the proteinuria level was 2.5 +/- 1 g/24 h. In group 2, the mean creatinine level was 1.9 +/- 0.6 mg/dL (168 +/- 53 micromol/L) (not significant [NS]) and the mean proteinuria level was 2.3 +/- 1.1 g/24 h (NS). Full remission occurred in 23% of the patients in group 1 (n = 8) and 17% of the patients in group 2 (n = 4; NS). Partial remission was observed in 38% of the patients in group 1 (n = 13) and 48% in group 2 (n = 11; NS). The number of patients who developed end-stage renal disease was comparable in both groups: 4 of 34 patients in group 1 after 2.5 +/- 0.8 years, and 5 of 23 patients in group 2 (NS).

CONCLUSION

Additional treatment with chlorambucil was found to be ineffective in FSGS. Patients responded to treatment with steroids or cyclosporine, but additional treatment with chlorambucil did not improve the patient's outcome. Future studies must focus on the long-term prognosis of these patients.

Serial estimates of serum permeability activity and clinical correlates in patients with native kidney focal segmental glomerulosclerosis

A serum or plasma factor in certain patients with focal segmental glomerulosclerosis (FSGS) has been found to increase glomerular albumin permeability (P(alb)) and causes proteinuria in experimental animals. High P(alb) is associated with recurrence of FSGS after transplantation, but serial studies of P(alb) activity in patients with native kidney FSGS have not been performed, and the relationship between P(alb) and remission of proteinuria is not known. This study was designed to determine P(alb) activity before, during, and after 24 wk of treatment with cyclosporine or placebo given as part of a randomized controlled trial in steroid-resistant FSGS patients with nephrotic range proteinuria. Pretreatment P(alb) averaged 0.36 +/- 0.22 and was not significantly different between treatment groups and was not altered during or after the test medication. There was no association between P(alb) activity and remission or relapse in proteinuria. The average P(alb) activity in native kidney FSGS was lower than in previously reported patients with posttransplant recurrence of the disease, and its level did not vary during the course of the study. The antiproteinuric effect of cyclosporine appeared independent of changes in P(alb). This finding is consistent with a direct effect of cyclosporine on glomerular barrier function and/or that within this group of patients the variations in proteinuria are not reflected in changes in Palb because of its limits in terms of reproducibility and responsiveness.

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.

Steroid-resistant, cyclosporine-responsive, relapsing nephrotic syndrome

Eighteen children with steroid-resistant nephrotic syndrome received cyclosporine A (CsA), including 7 patients with minimal change disease, 4 with focal segmental glomerulosclerosis and 7 with mesangial hypercellurarity. Doses were adjusted to maintain whole blood trough levels at 80-200 ng/ml and ranged from 5 to 10 mg/kg (mean 7 mg/kg). Fourteen patients responded after 2 months of therapy with either a complete or partial remission, and received a total of 12 months of CsA with low-dose corticosteroids. Remission rates were similar among the three histological types, although complete remissions occurred more commonly in minimal change disease, while the other two histological types tended to have partial responses. Serum creatinine values ranged from 0.3 to 1.2 mg/dl at the start of treatment and were stable in 17 of 18 patients during CsA therapy. CsA was discontinued after 12 months in 11 responders. Relapses were a significant problem. Nine patients had 16 relapses, all occurring within 6 months after discontinuing CsA; 13 of 16 relapses responded to CsA and corticosteroids. Five children had multiple relapses. Three patients who initially responded to treatment had CsA-resistant relapses. There were no differences among the histological types with respect to the occurrence of relapses or response to CsA after relapsing. Four patients developed chronic renal failure, including 2 of 4 who failed initial therapy and 2 of 3 who developed CsA-resistant relapses. In conclusion, initial therapy with CsA was effective in resolving nephrotic syndrome in steroid-resistant patients. However, CsA dependency, frequent relapses and the development of chronic renal failure presented significant problems.

Alternative treatment to corticosteroids in steroid sensitive idiopathic nephrotic syndrome

A review was undertaken of the use of alternative immunosuppressive treatment in addition to corticosteroids in a cohort of 429 children with steroid sensitive nephrotic syndrome (SSNS) treated between 1980 and 1994. Two hundred and twenty two children (52%) received at least one course of alternative treatment, 98 (23%) two, and 43 (10%) three. Cyclophosphamide was administered to 196 children (46%); in 181 it was the first course of alternative treatment and in 104 (57%) of those it was also the last ('final course'). Levamisole was given to 56 children (13%) and cyclosporin to 53 (12%). Fifteen children in whom cyclosporin failed were treated with chlorambucil. A few patients received azathioprine or vincristine. Ten children developed secondary steroid resistance, of whom five progressed to chronic renal failure. Acute complications included reversible renal failure, septicaemia, peritonitis, convulsions, and cerebral thrombosis. There were three deaths. It is concluded that half of the referred children with SSNS were deemed to require at least one course of alternative immunosuppressive treatment, and that side effects of the treatment and complications of SSNS are infrequent but occasionally fatal.

Lack of effect of isradipine on cyclosporin pharmacokinetics

The influence of isradipine as a long acting form (IcazR LP 5 mg) on cyclosporin pharmacokinetics was studied in six hypertensive renal transplant patients (mean age 37 yrs; mean body weight 62 kg). These patients received a mean daily cyclosporin dose of 307 mg in two equal intakes. Isradipine was orally administered once a day at a dose of 5 mg before the morning cyclosporin intake. Cyclosporin kinetics was assessed over a 0-12-h period, the day before (D-1) and 13 days (D+13) after isradipine treatment. Whole blood concentrations of cyclosporin were determined by radioimmunoassay (RIA) using the SandimmuneR-RIA kit (specific and non-specific monoclonal antibodies). Area under the blood concentration-time curve (AUC), the maximum blood concentration (Cmax) and the time to reach Cmax (Tmax) on D-1 and D+13 were not significantly different whatever the specificity of the RIA method. For example, the mean AUC +/- sd values were 5,247 +/- 2,255 (D-1) vs 5,317 +/- 1,675 (D+13) microgram.1(-1).h for the specific and 20,905 +/- 8,317 vs 19,327 +/- 5,758 microgram.1(-1).h for the non-specific determinations. Therefore, the pharmacokinetics of cyclosporin is not influenced by co-administration of isradipine at a therapeutic dosage. Moreover, the clinical results show that isradipine treatment was effective after 13 days administration (mean systolic blood pressure 132 vs 158 mm Hg, P < 0.05 and mean diastolic blood pressure 77 vs 93 mm Hg, P < 0.05 in supine position), and well tolerated throughout the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term low-dose cyclosporin A in steroid dependent nephrotic syndrome of childhood

Therapy of steroid-dependent idiopathic nephrotic syndrome is often unsatisfactory. Since 1986 we have treated nine children (six male and three female), aged 3-16 years, with cyclosporin A (CsA) during 2.0-5.2 (median 3.1) years. All had minimal change disease on renal biopsy and had previously received cyclophosphamide. Mean daily dosage of CsA was 4.1 mg/kg (range 2.7-5.8) and mean whole blood trough level was 220 ng/ml (range 141-271). The relapse rate decreased from 3.4/patient year before CsA to 0.55 on CsA. Discontinuation of CsA or reduction below 2 mg/kg daily was always followed by a relapse. The overall relapse rate, including the period with very low-dose CsA, was 0.95/patient year. Four patients required additional low-dose alternate-day prednisone. Repeat renal biopsy showed minimal change disease in eight patients and focal segmental glomerulosclerosis in one; CsA-toxicity was mild in two and moderate in one. The latter was the only patient with slightly reduced glomerular filtration rate. Two boys with delayed puberty spontaneously matured and reached expected final height. We conclude that long-term low-dose CsA is very effective and steroid-sparing. Its use is justified in selected patients, particularly in those with numerous relapses and in male patients before and during puberty, as long as renal function and CsA-toxicity are carefully monitored.

Cyclosporin reduces proteinuria in rats with aminonucleoside nephrosis

The effect of cyclosporin (CS) was assessed in Sprague-Dawley rats with puromycin aminonucleoside (PA) nephrosis induced by a single intraperitoneal injection of PA. Three groups of rats were injected intraperitoneally with CS (10 mg/kg body weight) daily, beginning 1 day before PA administration, or 5 or 10 days after PA administration, for 10 days. CS significantly reduced proteinuria in rats with PA nephrosis in comparison with untreated nephrotic controls. After discontinuation of the CS treatment, proteinuria gradually increased, reaching values similar to those in control nephrotic rats. CS pretreatment did not prevent the induction of PA-induced nephrotic syndrome. Light microscopy and assessment of anionic sites in the glomerular basement membrane revealed no differences between normal rats, nephrotic controls, and CS-treated rats. These results show that CS can reduce proteinuria in PA nephrosis, but cannot ameliorate the glomerular changes.

Practical aspects in the use of cyclosporin in paediatric nephrology

Many factors must be considered for the effective and safe use of cyclosporin A (CsA) in paediatric nephrology. Detailed knowledge of the variable bioavailability, tissue distribution, and metabolism, as well as causes which lead to their alteration are necessary. Factors which affect the activity of the mixed function oxidase system cytochrome P-450 must be considered, i.e. liver dysfunction and many drugs. Precise knowledge of the CsA determination method and the spectrum of metabolites is essential. In children with renal transplants, a body surface area-related dose will better meet the dose requirements than a body weight related-dose. For drug level monitoring whole blood rather than plasma should be used, and the parent drug level should be the main determinant; elevated metabolite levels may be important in suspected nephrotoxicity or liver dysfunction. Pharmacokinetic profiles are necessary to discover absorption problems or increased CsA clearance rates which necessitate shorter dosing intervals. In children with steroid-dependent minimal change nephrotic syndrome, remission without steroids is maintained as long as CsA is given. The appropriate starting dosage is 150 mg/m2 per day; trough level monitoring is mandatory to prevent nephrotoxicity and to confirm adequate immunosuppressive drug levels which should be 80-160 ng/ml (parent drug level). Although the benefit of CsA has been reported in some cases of lupus erythematosus, its use should be restricted to severe cases only until its efficacy and safety has been confirmed in controlled trials.

The treatment of minimal change nephrotic syndrome: lessons learned from multicentre co-operative studies

Minimal change nephrotic syndrome (MCNS) is the most frequent type of nephrotic syndrome in childhood. Treatment aims to induce remission, prevent relapses and avoid side-effects. MCNS is responsive to immunosuppressive therapy with glucocorticosteroids, alkylating drugs and cyclosporine A. From results of multicentre controlled studies it became evident that the initial treatment with prednisone should be intensive, i.e. for 12 weeks, in order to reduce the risk of subsequent relapses. Treatment of relapses should be standardized in order to categorize the patient's disease for further treatment. In case "frequent relapsers" develop signs of steroid-toxicity, they should be treated with alkylating drugs: frequent relapsers without steroid dependency with cyclophosphamide or chlorambucil for 8 weeks, steroid-dependent cases with cyclophosphamide for 12 weeks. If frequent relapses re-occur after cytotoxic drug therapy, treatment with cyclosporine A should be considered. Starting dose is 100-150 mg/m2 per day and needs to be adjusted to the whole blood trough level. Treatment with cyclosporine A must be strictly controlled in order to avoid chronic nephrotoxicity. Cyclosporine A does not cure MCNS. It is only effective as long as it is administered; therefore long-lasting treatment is necessary in most cases.

Cyclosporin reduces renal blood flow through vasoconstriction of arcuate arteries in the hydronephrotic rat model

Besides its beneficial effects in organ transplantation cyclosporin (CyA) exhibits nephrotoxic (and other) side effects. CyA nephrotoxicity is associated with a decrease in glomerular filtration rate. Two mechanisms of action have emerged. First, tubular destruction with secondary reduction in renal blood flow and glomerular filtration rate; second, decrease in renal blood flow with secondary interstitial fibrosis. We studied the effect of an acute infusion of CyA in the hydronephrotic rat kidney model, which lacks tubular structures completely. Hence, only the direct vascular effects of CyA were determined. Five groups (G) of rats were studied by television microscopy. G I (n = 7) received CyA (30 mg/kg, i.v.) dissolved in cremophore/plasma; G II (n = 5), time control 1, received cremophore/plasma instead of CyA; G III (n = 8), received CyA 30 mg/kg followed by 20 mg/kg CyA i.v. dissolved in an ethanol/tween solution; G IV (n = 3), time control 2 received ethanol/tween alone in the experimental period; in G V, CyA was applied locally onto the surface of the kidney with concentrations increasing from 10(-7) to 10(-5) M. CyA caused profound reduction in the diameter of arcuate arteries in groups I and III, in contrast to the time control groups II and IV. The vasoconstriction could be partially reversed by the calcium-channel blocker nitrendipine, and completely reversed with acetyl-choline. Glomerular blood flow decreased due to CyA and could not be completely normalized by either drug. Increasing the dosage from 30 to 50 mg/kg was not associated with further reduction in blood flow. Local application of CyA (G V) did not demonstrate vasoconstriction.(ABSTRACT TRUNCATED AT 250 WORDS)