Two-year cyclosporin treatment in children with steroid-dependent nephrotic syndrome

Childhood nephrotic syndrome

Idiopathic nephrotic syndrome is the most common glomerular disease in children. Corticosteroids are the cornerstone of its treatment, and steroid response is the main prognostic factor. Most children respond to a cycle of oral steroids, and are defined as having steroid-sensitive nephrotic syndrome. Among the children who do not respond, defined as having steroid-resistant nephrotic syndrome, most respond to second-line immunosuppression, mainly with calcineurin inhibitors, and children in whom a response is not observed are described as multidrug resistant. The pathophysiology of nephrotic syndrome remains elusive. In cases of immune-mediated origin, dysregulation of immune cells and production of circulating factors that damage the glomerular filtration barrier have been described. Conversely, up to a third of cases of steroid-resistant nephrotic syndrome have a monogenic origin. Multidrug resistant nephrotic syndrome often leads to kidney failure and can cause relapse after kidney transplant. Although steroid-sensitive nephrotic syndrome does not affect renal function, most children with steroid-sensitive nephrotic syndrome have a relapsing course that requires repeated steroid cycles with significant side-effects. To minimise morbidity, some patients require steroid-sparing immunosuppressive agents, including levamisole, mycophenolate mofetil, calcineurin inhibitors, anti-CD20 monoclonal antibodies, and cyclophosphamide. Close monitoring and preventive measures are warranted at onset and during relapse to prevent acute complications (eg, hypovolaemia, acute kidney injury, infections, and thrombosis), whereas long-term management requires minimising treatment-related side-effects. A subset of patients have active disease into adulthood.

IPNA clinical practice recommendations for the diagnosis and management of children with steroid-sensitive nephrotic syndrome

Idiopathic nephrotic syndrome is the most frequent pediatric glomerular disease, affecting from 1.15 to 16.9 per 100,000 children per year globally. It is characterized by massive proteinuria, hypoalbuminemia, and/or concomitant edema. Approximately 85-90% of patients attain complete remission of proteinuria within 4-6 weeks of treatment with glucocorticoids, and therefore, have steroid-sensitive nephrotic syndrome (SSNS). Among those patients who are steroid sensitive, 70-80% will have at least one relapse during follow-up, and up to 50% of these patients will experience frequent relapses or become dependent on glucocorticoids to maintain remission. The dose and duration of steroid treatment to prolong time between relapses remains a subject of much debate, and patients continue to experience a high prevalence of steroid-related morbidity. Various steroid-sparing immunosuppressive drugs have been used in clinical practice; however, there is marked practice variation in the selection of these drugs and timing of their introduction during the course of the disease. Therefore, international evidence-based clinical practice recommendations (CPRs) are needed to guide clinical practice and reduce practice variation. The International Pediatric Nephrology Association (IPNA) convened a team of experts including pediatric nephrologists, an adult nephrologist, and a patient representative to develop comprehensive CPRs on the diagnosis and management of SSNS in children. After performing a systematic literature review on 12 clinically relevant PICO (Patient or Population covered, Intervention, Comparator, Outcome) questions, recommendations were formulated and formally graded at several virtual consensus meetings. New definitions for treatment outcomes to help guide change of therapy and recommendations for important research questions are given.

Study protocol: mycophenolate mofetil as maintenance therapy after rituximab treatment for childhood-onset, complicated, frequently-relapsing nephrotic syndrome or steroid-dependent nephrotic syndrome: a multicenter double-blind, randomized, placebo-controlled trial (JSKDC07)

Background

Idiopathic nephrotic syndrome (INS) is the most common chronic glomerular disease in children. Approximately 80–90% of patients with childhood INS have steroid-sensitive nephrotic syndrome (SSNS), and can obtain remission with steroid therapy, while the remainder have steroid-resistant nephrotic syndrome (SRNS). Furthermore, approximately 50% of children with SSNS develop frequently-relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS). Children with FRNS/SDNS are usually treated with immunosuppressive agents such as cyclosporine, cyclophosphamide, or mizoribine in Japan. However, 10–20% of children receiving immunosuppressive agents still show frequent relapse and/or steroid dependence during or after treatment, which is defined as complicated FRNS/SDNS. Furthermore, 30% of SRNS patients who obtain remission after additional treatments such as cyclosporine also turn out to be complicated FRNS/SDNS. For such complicated FRNS/SDNS patients, rituximab (RTX) is currently used; however, recurrence after RTX treatment also remains an open issue. Because long-term use of existing immunosuppressive drugs has limitations, development of a novel treatment for maintenance therapy after RTX is desirable. Mycophenolate mofetil (MMF) is an immunosuppressive drug with fewer side effects than cyclosporine or cyclophosphamide. Importantly, recent studies have reported the efficacy of MMF in children with nephrotic syndrome.

Methods

We conduct a multicenter, double-blind, randomized, placebo-controlled trial to evaluate the efficacy and safety of MMF after RTX therapy in children with complicated FRNS/SDNS. Patients are allocated to either RTX plus MMF treatment group, or RTX plus placebo treatment group. For the former group, MMF is administered at a dose of 1000–1200 mg/m²/day (maximum 2 g/day) twice daily for 17 months after RTX treatment. The primary endpoint is time-to-treatment failure (development of frequent relapses, steroid dependence or steroid resistance).

Discussion

The results will provide important data on the use of MMF as maintenance therapy after RTX to prevent complicated FRNS/SDNS patients from declining into treatment failure. In future, MMF in conjunction with RTX treatment may permit increased duration of remission in ‘complicated’ FRNS/SDNS cases.

Trial registration

This trial was prospectively registered to UMIN Clinical Trials Registry on June 23, 2014 (UMIN Trial ID: UMIN000014347).

Efficacy and safety of rituximab in childhood-onset, difficult-to-treat nephrotic syndrome: A multicenter open-label trial in Korea

BACKGROUND

The anti-CD20 monoclonal antibody rituximab (RTX) has been proposed as a rescue therapy for difficult-to-treat nephrotic syndrome (NS). We conducted a clinical trial to evaluate the efficacy and safety of RTX in children with difficult-to-treat NS dependent on or resistant to steroids and calcineurin inhibitors (CNIs).

METHODS

A multicenter open-label trial was performed at 8 major pediatric nephrology centers in Korea. The investigation consisted of a randomized controlled trial for steroid- and CNI-dependent NS (DDNS; randomization into the RTX group and the control group, at a ratio of 2:1) and a single-arm study of steroid and CNI-resistant NS (DRNS). DDNS patients in the RTX group and DRNS patients received a single dose of intravenous RTX (375 mg/m of body surface area) for B-cell depletion. A second RTX dose was administered at week 2 if the first dose failed to achieve depletion of CD19(+) cells. The primary endpoint was rate of maintaining remission at 6 months after treatment for DDNS and rate of remission achievement for DRNS.

RESULTS

Sixty-one children with DDNS were enrolled while in remission and randomized to the control group (21 patients) or the RTX group (40 patients). At 6 months after treatment, the remission rates were 74.3% in the RTX group and 31.3% in the control group (P = .003). The mean duration of remission maintenance was significantly higher in the RTX group than in the control group (9.0 vs 2.9 months, P = .004). Of the 23 patients with DRNS enrolled in the single-arm study and treated with RTX, 9 (39.1%) achieved partial or complete remission within 6 months. Depletion of B cells occurred in all patients with RTX therapy. Thirty patients (50.8% of 59 patients analyzed) experienced mild and transient infusion reaction during RTX administration, and most adverse events were mild.

CONCLUSIONS

RTX administration was safe and effective in patients with difficult-to-treat NS. One or 2 doses of RTX may be sufficient to deplete B cells and achieve better control of pediatric NS.

Idiopathic nephrotic syndrome in children

The incidence of idiopathic nephrotic syndrome (NS) is 1·15-16·9 per 100 000 children, varying by ethnicity and region. The cause remains unknown but the pathogenesis of idiopathic NS is thought to involve immune dysregulation, systemic circulating factors, or inherited structural abnormalities of the podocyte. Genetic risk is more commonly described among children with steroid-resistant disease. The mainstay of therapy is prednisone for the vast majority of patients who are steroid responsive; however, the disease can run a frequently relapsing course, necessitating the need for alternative immunosuppressive agents. Infection and venous thromboembolism are the main complications of NS with also increased risk of acute kidney injury. Prognosis in terms of long-term kidney outcome overall is excellent for steroid-responsive disease, and steroid resistance is an important determinant of future risk of chronic or end-stage kidney disease.

Nephrotoxicity in children with frequently relapsing nephrotic syndrome receiving long-term cyclosporine treatment

BACKGROUND

Steroid-sparing drugs, such as cyclosporine, are recommended as treatment for children with frequently relapsing nephrotic syndrome (FRNS) and steroid-related toxicities. We recently reported a high rate of relapsing nephrotic syndrome 2 years after discontinuation of cyclosporine treatment, suggesting that long-term treatment is necessary. Cyclosporine-associated nephrotoxicity (CAN) is a potential side effect of long-term cyclosporine treatment.

METHODS

We retrospectively reviewed pediatric patients with FRNS treated with cyclosporine for ≥3 years at a single center between 1999 and 2012. The cyclosporine dose was adjusted to maintain the whole-blood cyclosporine trough level at 80-100 ng/ml for 6 months, at 60-80 ng/ml for 18 months, and then at around 50-60 ng/ml thereafter. Maintenance dose of prednisolone was not prescribed. CAN was graded in terms of arteriolar hyalinosis and the degree of interstitial fibrosis.

RESULTS

Thirty-six children (28 males) were enrolled in the study. The median age at the start of long-term cyclosporine treatment was 9.4 years. The median duration of the longest period of cyclosporine treatment was 4.5 years. Most CAN cases were characterized by arteriolar hyalinosis. The frequency of CAN was positively correlated with the duration of cyclosporine treatment, with an odds ratio (95% confidence interval) for CAN of 3.84 (0.79-18.74) after 2-5 years and 6.60 (1.18-36.94) after >5 years of cyclosporine treatment (vs. 0-2 years).

CONCLUSIONS

Although the frequency of CAN was correlated with the duration of cyclosporine treatment in our pediatric patient population, most cases of CAN involved arteriolar hyalinosis. We conclude that long-term cyclosporine treatment is useful for treating FRNS in children, providing its dose is controlled and kidney biopsies are regularly performed.

Cyclosporine A induced histological changes of Cathepsin L and CD2AP expression in renal glomeruli and tubules

BACKGROUND

Cyclosporine A (CsA) is used globally as an immunosuppressant for the treatment of immune-mediated nephrotic syndrome (NS). However, its long-term use causes nephrotoxicity characterized by tubulointerstitial injury and glomerulosclerosis. The present study aimed to investigate the associations between histomorphological findings and immunohistological expression of Cathepsin L (CatL) and CD2-associated protein (CD2AP) in patients with NS mediated with CsA.

METHODS

A total of 18 patients with child-onset NS were divided into two groups after treatment with CsA for 2 years (group A; n = 10) and more than 4 years (group B; n = 8), respectively. Analyses of relationships between tubulointerstitial disorders and expression of CatL and CD2AP proteins were performed using immunohistochemistry of paired renal specimens.

RESULTS

Glomeruli with arteriole hyalinization were significantly increased in both groups depending on dosage periods, although degrees of tubule and interstitial injury did not differ between groups. CD2AP expression was significantly greater in podocytes (P = 0.046) and was significantly less in proximal tubule cells (P = 0.014) in patients of group B compared with those of group A. Moreover, CD2AP expression was significantly increased in lateral tubule cells in both groups (group A, P = 0.02; group B, P = 0.001), and CatL expression in glomeruli and tubule cells did not change with the duration of CsA treatment in either patient group.

CONCLUSIONS

CD2AP expression in renal tubules may histologically associate with tissue hypoxia and reflected recovery from CsA-mediated renal injury in patients, even with mild histological features of tubulointerstitial disorder.

Rituximab Treatment for Nephrotic Syndrome in Children

In the past 10 years, many reports have suggested that rituximab, a chimeric anti-CD20 monoclonal antibody, is effective for children with complicated, frequently relapsing or steroid-dependent nephrotic syndrome (FRNS/SDNS). However, those reports were case reports, case series, retrospective surveys, and single-arm or short-term trials. Therefore, well-designed controlled trials are required to establish the value of rituximab in this condition. To evaluate the efficacy and safety of rituximab in childhood-onset, complicated FRNS/SDNS, a multicenter, double-blind, randomized, placebo-controlled trial was carried out by the Research Group of Childhood-onset Refractory Nephrotic Syndrome (RCRNS) in Japan (RCRNS01). RCRNS01 showed that rituximab is safe and effective for the treatment of childhood-onset, complicated FRNS/SDNS. In 2014, the use of rituximab for patients with complicated FRNS/SDNS was approved, first in the world, by the Ministry of Health, Labour and Welfare, Japan.

Rituximab for childhood-onset, complicated, frequently relapsing nephrotic syndrome or steroid-dependent nephrotic syndrome: a multicentre, double-blind, randomised, placebo-controlled trial

BACKGROUND

Rituximab could be an effective treatment for childhood-onset, complicated, frequently relapsing nephrotic syndrome (FRNS) and steroid-dependent nephrotic syndrome (SDNS). We investigated the efficacy and safety of rituximab in patients with high disease activity.

METHODS

We did a multicentre, double-blind, randomised, placebo-controlled trial at nine centres in Japan. We screened patients aged 2 years or older experiencing a relapse of FRNS or SDNS, which had originally been diagnosed as nephrotic syndrome when aged 1-18 years. Patients with complicated FRNS or SDNS who met all other criteria were eligible for inclusion after remission of the relapse at screening. We used a computer-generated sequence to randomly assign patients (1:1) to receive rituximab (375 mg/m(2)) or placebo once weekly for 4 weeks, with age, institution, treatment history, and the intervals between the previous three relapses as adjustment factors. Patients, guardians, caregivers, physicians, and individuals assessing outcomes were masked to assignments. All patients received standard steroid treatment for the relapse at screening and stopped taking immunosuppressive agents by 169 days after randomisation. Patients were followed up for 1 year. The primary endpoint was the relapse-free period. Safety endpoints were frequency and severity of adverse events. Patients who received their assigned intervention were included in analyses. This trial is registered with the University Hospital Medical Information Network clinical trials registry, number UMIN000001405.

FINDINGS

Patients were centrally registered between Nov 13, 2008, and May 19, 2010. Of 52 patients who underwent randomisation, 48 received the assigned intervention (24 were given rituximab and 24 placebo). The median relapse-free period was significantly longer in the rituximab group (267 days, 95% CI 223-374) than in the placebo group (101 days, 70-155; hazard ratio: 0·27, 0·14-0·53; p<0·0001). Ten patients (42%) in the rituximab group and six (25%) in the placebo group had at least one serious adverse event (p=0·36).

INTERPRETATION

Rituximab is an effective and safe treatment for childhood-onset, complicated FRNS and SDNS.

FUNDING

Japanese Ministry of Health, Labour and Welfare.

Cyclosporine C2 monitoring for the treatment of frequently relapsing nephrotic syndrome in children: a multicenter randomized phase II trial

BACKGROUND AND OBJECTIVES

An open-label, multicenter, randomized phase II trial was conducted from July 1, 2005 to March 29, 2011 to compare two protocols for treating children with frequently relapsing nephrotic syndrome using microemulsified cyclosporine.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Ninety-three children with frequently relapsing nephrotic syndrome were randomly assigned to group A (n=46) or group B (n=47). In both groups, the 2-hour postdose cyclosporine level was monitored. For group A, the cyclosporine target was set to 600-700 ng/ml for the first 6 months and 450-550 ng/ml for the next 18 months; for group B, it was set to 450-550 ng/ml for the first 6 months and 300-400 ng/ml for the next 18 months. The primary end point was the sustained remission rate. At the end of the study, if there was no difference in safety profile between the two groups and the sustained remission rate in group A was superior to group B with a decision threshold of 8%, then the regimen for group A would be determined the better treatment.

RESULTS

Eight children from an ineligible institution, where cyclosporine levels were not measured, were excluded from all analyses. At 24 months, the sustained remission rate was nonsignificantly higher in group A (n=43) than group B (n=42; 64.4% versus 50.0%; hazard ratio, 0.57; 95% confidence interval, 0.29 to 1.11; P=0.09), and the progression-free survival rate was significantly higher (88.1% versus 68.4%; hazard ratio, 0.33; 95% confidence interval, 0.12 to 0.94; P=0.03). The relapse rate was significantly lower in group A than group B (0.41 versus 0.95 times/person-year; hazard ratio, 0.43; 95% confidence interval, 0.19 to 0.84; P=0.02). The rate and severity of adverse events were similar in both treatment groups.

CONCLUSION

The sustained remission rate was not significantly different between the two treatment groups, but the regimen with the higher 2-hour postdose cyclosporine level target improved progression-free survival and reduced the relapse rate.

Cyclosporin A may cause injury to undifferentiated glomeruli persisting in patients with Alport syndrome

BACKGROUND/AIMS

Alport syndrome (AS) is a renal disorder caused by a genetic abnormality of type IV collagen α3 and α4, or α5 genes and shows a poor prognosis. Since the defect of type IV collagen synthesis disturbs the maturation process of the glomerular capillary loop, residual immature glomeruli persist after birth. The therapeutic efficacy of cyclosporin A (CyA) for AS patients seems to be controversial. We recently noted that renal specimens obtained from a child with AS who was treated with CyA and then developed CyA nephropathy included an increased number of undifferentiated embryonic-type glomeruli.

METHODS

We analyzed renal histologic and immunohistologic findings in children with AS who did (n = 3) or did not (n = 2) develop CyA-induced nephropathy despite appropriately low serum CyA concentrations (<100 ng/mL) being maintained over a period of 2 years. To discriminate embryonic-type from mature glomeruli, staining for type IV collagen α1, laminin β1, and laminin β2 accompanied by light microscopic observation were employed. Staining patterns were used to semiquantitatively assess glomerular immaturity (glomerular immaturity index, or GII).

RESULTS

In initial biopsy specimens, residual embryonic-type glomeruli were observed in each patient. Patients with early-onset CyA nephropathy had a high GII (median value 2.91 vs 1.23 ± 0.62 normal kidney tissues). In the follow-up biopsy after CyA treatment, surviving embryonic-type, collapsing embryonic-type, and sclerotic glomeruli that had failed to differentiate were observed. Taken together, the number of these glomeruli essentially equaled the total number of embryonic-type glomeruli in specimens obtained before CyA treatment.

CONCLUSIONS

Our findings indicate a need for caution in CyA therapy for patients with AS, even for a relatively short course of administration, because some patients may have an unexpected number of embryonic-type glomeruli that predispose to CyA nephropathy.

Two-year follow-up of a prospective clinical trial of cyclosporine for frequently relapsing nephrotic syndrome in children

BACKGROUND AND OBJECTIVES

Although the safety and efficacy of cyclosporine in children with frequently relapsing nephrotic syndrome (FRNS) have been confirmed, no prospective follow-up data on relapse after cyclosporine have appeared. This study is a prospective follow-up trial after 2-year treatment with cyclosporine to investigate cyclosporine dependency after its discontinuation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Participants who had undergone 2-year protocol treatment with microemulsified cyclosporine for FRNS between January 2000 and December 2005 were followed for an additional 2 years. The primary end point was relapse-free survival after the complete discontinuation of cyclosporine, and the secondary end point was regression-free survival (time to regression to FRNS).

RESULTS

After exclusion of 7 patients who showed regression to FRNS during the 2-year treatment period, 49 children (median age, 6.5 years) were followed, and classified as children without (n=32; group A) and with (n=17; group B) relapse during the initial cyclosporine treatment. Overall, relapse-free survival probability at 24 months after cyclosporine discontinuation was 15.3% and regression to FRNS-free survival probability was 40.8%. By group, the probability of relapse-free survival was significantly higher in group A (17.9%) than in group B (8.3%) (P<0.001).

CONCLUSIONS

Children with FRNS who receive cyclosporine are at high risk of relapse after discontinuation, particularly those who experience relapse during cyclosporine treatment.

Complete remission induced by tacrolimus and low-dose prednisolone in adult minimal change nephrotic syndrome: A pilot study

Background

Few clinical trials have examined the replacement of steroids with other immunosuppressive drugs as a primary treatment modality for minimal change disease (MCD) in adults. We studied the efficacy of tacrolimus to induce complete remission (CR) in adults with MCD.

Methods

We enrolled 14 adults with MCD and nephrotic-range proteinuria. All patients were treated with oral tacrolimus 0.05 mg/kg twice daily and prednisolone 0.5 mg/kg/day. CR was defined as a urine protein to creatinine ratio of<0.2 g protein/g creatinine (g/g cr). The primary outcome was cumulative percentage of CR during 16 weeks.

Results

The mean urine protein to creatinine ratio at enrollment was 10.9 g/g cr (range: 4.2–18.1 g/g cr). The trough tacrolimus level was maintained at 5.99±2.63 ng/mL. CR was achieved by 13/14 (92.8%) patients within 8 weeks. The cumulative CR rate was 7.7% (1/14), 64.2% (9/14), 71.3% (10/14), and 92.9% (13/14) at 1 week, 2 weeks, 4 weeks, and 8 weeks, respectively. The one remaining patient achieved CR at 20 weeks after treatment, who was followed up for a further 4 weeks. The mean time to achieve CR in the 14 patients was 4.64±5.11 (1–20) weeks. Three cases suffered adverse events of abdominal pain, diarrhea, or new-onset diabetes mellitus.

Conclusion

Tacrolimus and low-dose prednisolone therapy induced CR rapidly (71.3% by 4 weeks and 100% by 20 weeks) and effectively in adult patients with MCD.

Rituximab for childhood refractory nephrotic syndrome

Several therapies including immunosuppressive agents have been shown to be effective and safe for frequently relapsing nephrotic syndrome/steroid-dependent nephrotic syndrome (FRNS/SDNS) and steroid-resistant nephrotic syndrome in children. It is evident, however, that a substantial number of children are still refractory to treatment despite these therapies. Rituximab is a chimeric monoclonal antibody, which inhibits CD20-mediated B-cell proliferation and differentiation. It was first introduced for the treatment of B-cell non-Hodgkin's lymphoma and was subsequently administered to patients with autoimmune diseases, such as rheumatoid arthritis, lupus erythematosus, or immunocomplex glomerulonephritis. Recently, a number of case reports and non-controlled clinical trials have suggested that rituximab may be effective for children with refractory nephrotic syndrome. Controlled prospective trials, however, are required to establish the value of rituximab in refractory nephrotic syndrome. The purpose of the present study was therefore to evaluate the efficacy and safety of rituximab in childhood-onset refractory nephrotic syndrome. The Research Group of Childhood-onset Refractory Nephrotic Syndrome (RCRNS) conducted a randomized, double-blind, placebo-controlled, multi-center clinical trial (RCRNS-01) and an open-label, multi-center, pharmacokinetic clinical trial (RCRNS-02). These two trials were investigator-initiated, registration-directed clinical trials designed to apply Ministry of Health, Labour and Welfare approval for the use of rituximab for childhood-onset refractory FRNS/SDNS in Japan. RCRNS-01 could be the first study to clarify whether rituximab is effective and safe for childhood-onset refractory FRNS/SDNS.

Novel multidrug therapy for children with cyclosporine-resistant or -intolerant nephrotic syndrome

An effective treatment for children with refractory nephrotic syndrome (NS), especially in those with cyclosporine (CsA)-resistant or CsA-intolerant NS, has yet to be established. Recently, the efficacy of multidrug therapy consisting of tacrolimus (Tac), mycophenolate mofetil (MMF) in combination with prednisolone (PDN) in adult patients with refractory NS has been reported. We successfully treated 14 consecutive children with refractory CsA-resistant or CsA-intolerant NS using combination therapy consisting of relatively low-dose Tac, mizoribine (MZR), which has a mechanism of action very similar to that of MMF, and PDN. There were no serious clinical toxicities. Of the 14 children, 9 with a mean age of 13.0 years had steroid-dependent NS (SDNS) and 5 with a mean age of 9.6 years had steroid-resistant NS (SRNS). All SDNS patients had minimal change disease (MCD), 4 with SRNS had focal segmental glomerulosclerosis (FSGS), and the remaining child had MCD on renal biopsy. All patients were in a prospective cohort, but were evaluated retrospectively. The mean follow-up from the initiation of multidrug therapy was 18.4 months in SDNS and 18.6 months in SRNS patients. At the last observation point, the calculated relapse rate and minimum dose of PDN required for maintenance of clinical remission after the start of multidrug therapy were significantly decreased compared with those prior to this therapy, while on CsA, in SDNS patients (0.4 ± 0.5 times/year vs 2.9 ± 1.5 times/year, P = 0.0077, and 0.3 ± 0.2 mg/kg on alternate days vs 0.5 ± 0.2 mg/kg on alternate days, P = 0.0184 respectively). All SDNS and two SRNS patients (40%) achieved complete remission, allowing further decreases in the minimal doses of PDN required for maintenance of clinical remission in most our patients. However, one patient with FSGS remained refractory to multidrug therapy and subsequently developed end-stage renal disease. These clinical observations, although preliminary and involving a small number of patients, suggest that multidrug therapy consisting of relatively low-dose Tac, MZR, and PDN might be effective and safe for treating children with refractory CsA-resistant or CsA-intolerant NS. However, further studies involving larger numbers of patients are needed.

Predictive factors for ciclosporin-associated nephrotoxicity in children with minimal change nephrotic syndrome

Aims

To identify the predictive factors for ciclosporin A (CyA)-associated nephrotoxicity (CAN) in children with minimal change nephrotic syndrome (MCNS).

Methods

The clinical and laboratory findings of 58 children (median age 3.2 years, range 1.1–13.1 years, male:female 48:10) with MCNS who were treated with CyA from 1992 to 2002 were analysed retrospectively. Forty-eight (83%) of them were steroid dependent and 10 (17%) were steroid resistant. The starting dose of CyA was 5 mg/kg per day, and the desired drug level was kept at 100–200 ng/ml. Serial renal biopsies were performed before and after CyA therapy.

Results

Twenty-two patients (38%) had CAN (group I) and 36 (62%) did not (group II). There were no differences in the age at onset, sex, initial response to steroids, duration of CyA therapy and relapse rates. However, the median CyA trough levels were significantly higher in group I than in group II (218.0±15.2 vs 171.8±6.7 ng/ml, p=0.01). Changes in creatinine clearance were more decreased in group I than in group II (−39.4±8.2 vs 2.7±4.3 ml/min per 1.73 m2, p<0.0001). Multiple logistic regression analysis also revealed the median CyA trough level was an independent risk factor for the development of CAN (OR 1.025, 95% CI 1.007 to 1.044, p=0.007).

Conclusions

The median CyA trough level was an independent and significant risk factor for the development of CAN in children with MCNS receiving moderate-dose CyA.

Cyclosporin A therapy for Henoch-Schönlein nephritis with nephrotic-range proteinuria

To evaluate the therapeutic role of cyclosporin A (CyA) for the treatment of Henoch-Schönlein nephritis (HSN), 29 patients (18 boys, 11 girls) with nephrotic-range proteinuria were analyzed retrospectively. Mean age was 8.6 years (range 2.0-15.5 years) at diagnosis of Henoch-Schönlein purpura (HSP). All patients had developed the nephrotic-range proteinuria at a mean interval of 4.4 months (range 0-50.7 months) after the diagnosis of HSP. Mean duration of CyA treatment was 12.3 months (range 2.6-55.0 months). Mean follow-up times were 3.7 years (range 1.2-12.9 years) from the beginning of the CyA treatment. Steroids were tapered off and stopped gradually after initiation of CyA. All patients responded to the CyA treatment within a mean of 1.8 months (range 1 week to 3.5 months). Twenty-three patients achieved stable remission with mean follow-up duration of 3.2 years and 6 patients seemed to become CyA-dependent, since they developed proteinuria when the treatment was stopped. Renal function was preserved in all patients but one who developed end-stage renal disease after poor compliance with CyA. We concluded that CyA treatment for HSN showing nephrotic-range proteinuria is very effective and a safe method, although some patients become CyA-dependent.

Effect of cyclosporine therapy with low doses of corticosteroids on idiopathic nephrotic syndrome

Cyclosporine (CyA) has an immunosuppressive effect that might suggest a therapeutic role in idiopathic glomerular conditions. We focused on the optimization of CyA treatment control in patients with idiopathic nephrotic syndrome by using trough-level CyA measurements (C0) and the 2-h postdose levels (C2). Twenty-two patients (14 male, 8 female) with idiopathic nephrotic syndrome and the mean age of 51 +/- 18 months (mean [M] +/- standard deviation [SD]) were enrolled in our study during a period of 10 months (range: 3-18 months). All of the patients received CyA (2-3 mg/kg) in combination with methylprednisolone. In the present study protocol CyA concentrations (C0, C2), renal function, lipid profile, and degree of proteinuria were determined. The mean proteinuria of our patients before treatment was 11 972 +/- 7953 mg/24 H (+/-SD) and the mean creatinine level (Cr) was 0.99 +/- 0.37 mg/dL (+/-SD). Proteinuria decreased significantly already from the first month of therapy with CyA to 3578 +/- 2470 mg/24 H (M+/- SD), and during the whole study period this reduction was significant (0.56 +/- 0.37 gr/24 H (M +/- SD), P < 0.05). At the same time renal function preserved, 1.09 +/- 0.48 mg/dL (M +/- SD). The blood levels of C0 were 135.10 +/- 97.36 ng/mL (M +/- SD) and the blood levels of C2 were 725 +/- 256 ng/mL (M +/- SD) at the first month of therapy. At the same time renal function preserved, 1.09 +/- 0.48 mg/dL (M +/- SD). Total cholesterol levels reduced significantly during study period (276.89 +/- 45.57 to 200.67 +/- 40.27 mg/dL [M +/- SD]). The mean number of antihypertensive medication remained the same. The whole therapeutic protocol did not provoke any kind of side effects and CyA was quite tolerated by our patients. Treatment of idiopathic nephrotic syndrome with low doses of CyA with methylprednisolone leads to remission of proteinuria without deterioration of renal function. Blood levels of C0 for monitoring and treatment of nephrotic syndrome agrees with recent literature, while our study focus on establishing the proper levels of C2 for the treatment of nephrotic syndrome. The efficacy of CyA is combined with safety and tolerance.

Benefits of once-daily administration of cyclosporine a for children with steroid-dependent, relapsing nephrotic syndrome

Cyclosporine A (CsA) is an effective steroid-sparing agent for patients with steroid-dependent, relapsing nephrotic syndrome (SDRNS). The efficacy and safety of single-daily dose administration (SDD protocol) of CsA in selected patients with SDRNS has been reported. However, the efficacy of initial CsA treatment for children with SDRNS using the SDD protocol remains to be elucidated. The SDD protocol might be associated with lower clinical toxicity, compared to the conventional twice-daily dose administration (TDD protocol). Here we evaluated the efficacy and safety of the SDD protocol versus the TDD protocol in patients with SDRNS. The data from 19 patients (9.9 +/- 4.2 years old) were retrospectively collected and analyzed. Ten patients treated according to the SDD protocol for a mean of 27 months (SDD group), while 9 patients treated with the TDD protocol for a mean of 35 months (TDD group) as an initial CsA treatment. Although the mean daily CsA dose was significantly lower in the SDD group (1.5 +/- 0.4 mg/kg/day vs. 3.7 +/- 0.7 mg/kg/day, P < 0.01), there were no differences between the two groups in the mean minimum dose of prednisolone required for maintenance of clinical remission nor in the calculated relapse rate. One patient in the TDD group developed biopsy-proven mild CsA nephrotoxicity, whereas no patient in the SDD group showed nephrotoxicity. Despite a small number of patients, this study may support that the SDD protocol is at least as effective as the conventional TDD protocol, and is more cost-effective for selected children with SDRNS.

Cyclosporine and steroid therapy in children with steroid-resistant nephrotic syndrome

We conducted a prospective, multicenter trial to evaluate the efficacy and safety of a 12-month course of cyclosporine in children with steroid-resistant nephrotic syndrome (SRNS). Thirty-five patients were enrolled, of whom 28 had minimal change or diffuse mesangial proliferation (MC/DMP), and seven had focal segmental glomerulosclerosis (FSGS). All patients received cyclosporine and prednisolone; patients with FSGS additionally received methylprednisolone pulse therapy (MPT). The dose of cyclosporine was adjusted to maintain a trough level of 120-150 ng/ml during the initial 3 months of treatment, followed by 80-100 ng/ml during months 4-12. The primary end point was the remission rate at month 12. Remission was achieved in 23 of 28 (82.1%) patients in the MC/DMP group and in six of the seven (85.7%) patients in the FSGS group. Follow-up renal biopsies were performed in 26 patients (nine at month 12, 17 at month 24), and cyclosporine-related nephrotoxicity was detected in one (3.8%). Major adverse events comprised severe bacterial infections (two patients) and posterior reversible encephalopathy syndrome (one patient). In conclusion, a high remission rate was achieved in our patient cohort using a combined cyclosporine/ prednisolone treatment regimen in children with SRNS who had MC/DMP and a combined cyclosporine/prednisolone plus MPT regimen in children who had FSGS.

Risk factors for cyclosporin A nephrotoxicity in children with steroid-dependant nephrotic syndrome

BACKGROUND AND OBJECTIVES

Cyclosporin A (CsA) is a well-established treatment for steroid-dependent nephrotic syndrome (SDNS) that may, however, cause chronic ischemic renal lesions. The objective of the study was to assess the prevalence of CsA nephrotoxicity (CsAN) in protocol biopsies of children with SDNS.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

From 1990 through 2008, we performed 71 renal biopsies in 53 patients with SDNS. The mean CsA C2 levels were 466 +/- 134 ng/ml, and the mean duration of treatment was 4.7 +/- 2.0 yr before biopsy (range 2.9 to 12.7 yr).

RESULTS

CsAN was observed in 22 (31%) of 71 renal biopsies. Of these, 11 corresponded to isolated vascular or tubular lesions, and 11 corresponded to combined vascular and tubular lesions. The majority of CsAN lesions were mild (17 of 22). In no cases were lesions graded as severe. By regression analysis, CsAN was positively associated with the use of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) and with hyperuricemia and negatively associated with minimal-change lesions. By multivariate analysis, only association with the use of ACEIs or ARBs retained significance. Stratification of the population according to CsA C2 levels showed increased risk for CsAN for C2 levels >600 ng/ml.

CONCLUSIONS

Mild to moderate CsAN occurs in approximately one third of patients who have SDNS and are treated with CsA for >3 yr. Our data suggest that patients who require high dosages of CsA or treatment for hypertension, in particular when ACEIs/ARBs are used, are at higher risk for CsAN.

Successful use of single-dose rituximab for the maintenance of remission in a patient with steroid-resistant nephrotic syndrome

We present the case of a 23-year-old man with steroid-resistant nephrotic syndrome due to minimal change disease who was treated with rituximab. The patient was resistant to conventional therapy. We therefore treated him with a single dose of rituximab (375 mg/m(2)). One month after the administration of rituximab, complete remission was achieved. However, six months later, the patient was administered a second dose of rituximab as the peripheral B cell counts began to recover. Thereafter, at present, that is, one year after the first rituximab administration, complete remission has been maintained. We conclude that rituximab may be an effective treatment agent for resistant nephrotic syndrome and the peripheral B cell count may be a useful marker in such patients for preventing disease relapse.

Cyclosporine-A-induced nephrotoxicity in children with minimal-change nephrotic syndrome: long-term treatment up to 10 years

The impact of cyclosporine A (CsA) therapy in patients with steroid-dependent nephrotic-syndrome (SDNS) on long-term renal function is controversial. Data beyond 5 years are rare. Long-term renal function was evaluated in children with SDNS with and without CsA therapy, especially beyond 5 years. Twenty children were treated with CsA (study group) for a mean of 5.4 +/- 2.2 years (ten patients for 5-11 years). Glomerular filtration rate (GFR) was calculated before and after 3 and 12 months and at latest follow-up of therapy. Fifteen children with cyclophosphamide-treated SDNS without CsA served as controls. In the study group, GFR decreased within 12 months from 136 +/- 19 to 120 +/- 31, to 114 +/- 14 ml/min per 1.73 m(2) at latest follow-up (p < 0.0001). Patients with CsA > 5 years had a GFR of 111 +/- 14 ml/min per 1.73 m(2) at latest follow-up without a GFR below 90 ml/min per 1.73 m(2). No CsA toxicity was found in biopsies. In the control group, GFR dropped within 3 months, from 137 +/- 27 to 130 +/- 24, to 126 +/- 19 ml/min per 1.73 m(2) at latest follow-up (p = 0.1). Patients with and without nephrotoxic CsA therapy showed a drop in GFR. In CsA-treated patients, GFR was about 12% lower at latest follow-up compared with patients without nephrotoxic therapy but always remained within normal range. CsA seems to be safe, even in long-term treatment for more than 5 years.

Unexpected efficacy of rituximab in multirelapsing minimal change nephrotic syndrome in the adult: first case report and pathophysiological considerations

Nephrotic syndrome secondary to minimal change disease (MCNS) usually is considered to have a good renal prognosis, but frequency of relapses and steroid dependency are therapeutic challenges to physicians. Treatment of patients with multiple relapses remains controversial because few control studies are available. We report the case of a 23-year-old woman of Malian origin who experienced more than 30 relapses of MCNS. Long-term remission was observed only with rituximab (anti-CD20 antibody) treatment after step-by-step use of all currently available medications for MCNS were unsuccessful. Our observation is the first report of efficacy of rituximab during multirelapsing MCNS in an adult patient with a significant follow-up and no adjuvant therapy. This case suggests a role of B cells in MCNS, possibly by regulating T-cell function.

Management of steroid-resistant focal segmental glomerulosclerosis in children using tacrolimus

BACKGROUND

The use of tacrolimus in steroid-resistant (SR) focal segmental glomerulosclerosis (FSGS) has been reported in single and small series case reports.

AIM

To determine the efficacy of tacrolimus in the management of SR FSGS in children.

STUDY DESIGN

This was a prospective study of 20 children with SR FSGS treated with tacrolimus (0.2-0.4 mg/kg/day in two divided doses over 12 h adjusted to a trough level between 7 and 15 ng/ml) for 12 months in combination with low-dose steroids. Other therapies included angiotensin-converting enzyme inhibitors, folic acid, multivitamins and lipid-lowering agents.

RESULTS

The mean age at study entry was 11.1 years (range 5.6-16.8). The mean duration of nephrotic syndrome before initiation of tacrolimus therapy was 4.7 years (range 2.1-7.6). At the end of the treatment period, 8 (40%) children were in complete remission, 9 (45%) were in partial remission, and 3 (15%) failed to respond. The average follow-up period following cessation of tacrolimus treatment was 27.5 months (range 13.7-43.7). At last hospital follow-up, 5 (25%) children were in complete remission, 10 (50%) in partial remission, and 2 (10%) in relapse. Three children died from dialysis-related complications following cessation of tacrolimus treatment. Adverse events included sepsis (2), nausea (2), diarrhea (2), anemia (4) and worsening of hypertension (4).

CONCLUSION

Tacrolimus is a safe and effective treatment for SR FSGS. However, like cyclosporine, some children tend to relapse following cessation of treatment.

Expression of P-glycoprotein in lymphocytes from children with nephrotic syndrome, depending on their steroid response

The aim of this study was to examine the expression of P-glycoprotein (P-gp) in CD3 lymphocytes of children with nephrotic syndrome (NS) in relation to their clinical response to glucocorticoid (GC) treatment. The examinations were performed on two groups. The study group (I) consisted of 88 children aged 2.0-20.0 years with NS, divided according to their clinical response to GC: NFR-non-frequent relapse NS; FR-frequent relapse NS; SD-steroid-dependent NS. The control group (II) consisted of 18 healthy children never treated with GC. We measured P-gp expression on CD3 lymphocytes of patients with NS using a flow cytometry assay. The CD3/P-gp was significantly higher than in controls. The difference was higher in SD (P=0.0001) and FR - (P=0.0002) group. The difference in NFR was smaller. Mean CD3/P-gp (in percent) was twice as high in SD children than in NFR, and the difference, as between FR and NFR, was statistically significant (P<0.01). Worse response to GC or dependency may be due to overexpression of P-gp. Further examinations are necessary to establish whether increased P-gp activity is a result of MDR-1 polymorphism and to determine GC response, or to ascertain if such activity is only a result of GC therapy.

Independent risk factors for chronic cyclosporine induced nephropathy in children with nephrotic syndrome

BACKGROUND

Cyclosporine A (CsA) has been widely used in children with steroid dependent and steroid resistant nephrotic syndrome (NS) because of its efficacy in relieving these patients from systemic side effects of steroids. However, its long term use is controversial, since chronic CsA induced nephropathy (CsAN) may develop in a considerable number of patients.

AIMS AND METHODS

In order to clarify the risk factors for the development of CsAN, the clinical characteristics of children with steroid dependent or steroid resistant NS taking CsA (target blood trough levels 50-150 ng/ml) for more than six months, managed at a single centre, were retrospectively analysed.

RESULTS

Thirteen of 30 children (24 boys and 6 girls) taking CsA (mean duration 43 months, range 6-144) had CsAN defined as the presence of CsA associated arteriopathy with or without striped tubulointerstitial lesions. The multivariate analysis revealed that CsA treatment for more than 36 months and an age younger than 5 years at the start of CsA treatment were independent risk factors for the development of CsAN. The univariate analysis also showed that patients with CsAN had more frequent relapses during CsA treatment than those without CsAN.

CONCLUSION

An alternative treatment should be seriously considered after a 36 month administration of CsA in order to prevent CsAN. Data also suggest that CsA treatment in children younger than 5 years should be avoided if possible.

Renal biopsy findings in children receiving long-term treatment with cyclosporine a given as a single daily dose

Long-term treatment of childhood nephrotic syndrome (NS) and rheumatic diseases with cyclosporine A (CsA) given as a single daily dose may yield better results and allow safer use of the drug than the conventional twice-daily dosing. However, the safety of such long-term treatment from the histological standpoint remains to be established. Posttreatment renal biopsy was conducted in a total of eight children (5 with minimal change NS, 2 with focal segmental glomerulosclerosis and 1 with X-linked immune dysregulation, polyendocrinopathy and enteropathy) receiving CsA as a single daily dose, after a mean treatment duration of 20 months (9-36 months). The initial daily dose of CsA (Neoral) was 2.0 mg/kg, given as a single daily dose before breakfast. The dose was subsequently adjusted to achieve a peak (between 1 and 2 hrs post-dosing, C1-C2) blood level of around 800 ng/ml. The mean daily CsA dose, mean C1-C2 blood level, and mean trough blood level in the subjects were 1.9 +/- 0.6 mg/kg, 803.8 +/- 117.2 ng/ml and 36.1 +/- 12.7 ng/ml, respectively. The result revealed no evidence of CsA-related nephrotoxicity, including arteriopathy, striped interstitial fibrosis or tubular atrophy, in any of the study participants. Also, no significant changes were observed in the mean estimated glomerular filtration rate as compared to the pretreatment values (127.6 +/- 14.9 ml/min/1.73 m(2) vs 115.6 +/- 22.8 ml/min/1.73 m(2), and except for mild hypertrichosis, no significant adverse effects of CsA were observed. These findings lend further support to the safety of long-term low-dose CsA treatment (median treatment duration in this study, 20 months), with the drug administered as a single daily dose while maintaining a peak (C1-C2) blood level of around 800 ng/ml.

Impact of the cyclosporine-ketoconazole interaction in children with steroid-dependent idiopathic nephrotic syndrome

BACKGROUND

Children with steroid-dependent nephrotic syndrome experience serious side effects from steroid therapy. Cyclosporine A (CsA), which is an effective agent in the treatment of steroid-dependent nephrotic syndrome, is expensive and, consequently, often unaffordable in developing countries. Many studies have documented the benefit of ketoconazole administration in transplant adults treated with CsA. We have conducted a retrospective study with the objective of addressing cost-savings, safety, and the efficacy of the co-administration of ketoconazole and CsA to children with steroid-dependent nephrotic syndrome.

METHODS

This study included 102 nephrotic patients who were steroid-dependent and who received cyclosporine therapy. The commonest pathologic lesions were focal segmental glomerulosclerosis (64 patients) and minimal change disease (36 patients). Among the patients participating in the study, 78 received daily ketoconazole therapy (ketoconazole group) in the form of a 50-mg dose accompanied by an initial one-third decrease in the CsA dose, while 24 received CsA alone (non- ketoconazole group). All of the patients were children (below 18 years), and the male-to-female ratio was 3:1. The mean duration of treatment was 22.9 months. The characteristics of both groups were comparable.

RESULTS

Co-administration of ketoconazole significantly reduced mean doses of CsA by 48% with a net cost savings of 38%. It also resulted in a significant improvement in the CsA response and a more successful steroid withdrawal as well as a decrease in the frequency of renal impairment. Liver function tests remained normal in both groups up to and including the final follow-up (mean of 33.6 months).

CONCLUSIONS

The co-administration of ketoconazole to CsA in children with idiopathic steroid-dependent nephrotic syndrome safely results in a significant reduction in CsA cost, which causes great concern in developing countries. It may also improve CsA response.

Long-term effects of cyclosporine in children with idiopathic nephrotic syndrome: a single-centre experience

BACKGROUND

Because of its potential nephrotoxicity, the long-term use of cyclosporine (CsA) as treatment for nephrotic syndrome (NS) is controversial. The clinical outcome of the patients with NS treated with CsA is unclear.

METHODS

This study reports the results of long-term CsA treatment in 117 children with idiopathic NS, who received CsA therapy for more than 2 years (median, 34 months). The mean age of children at initiation of CsA therapy was 11+/-4 years. The starting dose of CsA was 5 mg/kg/day, adjusted to maintain a trough level of 100-150 ng/ml in the first 2 months, 50-100 ng/ml thereafter. Later, a level as low as 30 ng/ml was accepted so long as it maintained remission. All patients received CsA between 1993 and 2003. Indications for treatment included steroid-dependent nephrotic syndrome (SDNS) in 74 patients and steroid-resistant nephrotic syndrome (SRNS) in 43 patients. Initial renal histology showed minimal change disease (MCD) in 38 patients and focal segmental glomerulosclerosis (FSGS) in 79 patients. Most patients were receiving moderate doses of prednisone. Sixty patients received cyclophosphamide prior to CsA. The observation periods were 5.8+/-3 years and 6.1+/-1.9 years before and after CsA treatment, respectively.

RESULTS

Complete remission [proteinuria <4 mg/h/m2/body surface area (BSA)], partial remission (proteinuria between 4.1 and 40 mg/h/m2/BSA) and resistance to CsA (proteinuria > or = 45 mg/h/m2/BSA) were observed in 82.1, 5.1 and 12.8%, respectively. Hypertension, renal impairment (>30% rise of serum creatinine), gingival hyperplasia and hypertrichosis occurred in 10.3, 6.0, 32.5 and 70.1%, respectively. Steroids were stopped in 102 patients, of which 31 relapsed. Out of 29 patients for whom CsA was intentionally discontinued while in remission, 22 relapsed. Of these, six patients were resistant to a second course of CsA. Post-therapy biopsies, performed in 45 patients (33 with SDNS and 12 with SRNS), showed mild stripped interstitial fibrosis and tubular atrophy in two SDNS patients (4.4%). At the last follow-up, one child had developed end-stage renal failure and two had chronic renal insufficiency.

CONCLUSIONS

Long-term CsA therapy in low doses is effective in the treatment of children with idiopathic NS, but the rate of relapse is high after drug withdrawal. Hypertension developed in 10% of patients and renal insufficiency in 6% (most patients with FSGS).

Mycophenolate mofetil therapy in frequently relapsing steroid-dependent and steroid-resistant nephrotic syndrome of childhood: current status and future directions

Clinicians are often faced with therapeutic dilemmas and challenges while treating children with frequently relapsing steroid-dependent nephrotic syndrome (SDNS) and steroid-resistant nephrotic syndrome (SRNS). In the past, children with SDNS have been treated with long-term alternate day steroids cyclophosphamide, cyclosporine (CSA), chlorambucil, levamisole, and azathioprine. The essential aim of these therapies is to maintain remission while limiting exposure to steroids. These medications have variable efficacy and undesirable toxicity profiles. Recently, mycophenolate mofetil (MMF) has emerged as a new therapeutic option for the management of SDNS in a few uncontrolled clinical trials. Preliminary data are encouraging. MMF was found to be useful in maintaining remission and has a steroid-sparing effect. Clearly, more data are needed to further characterize the safety and efficacy of MMF, define adequate length of treatment, and optimize drug exposure and monitoring. The management of SRNS is primarily aimed at decreasing proteinuria and inducing remission, if possible. By doing so, one would aim to preserve renal function. CSA therapy is known to be useful in this regard but has undesirable side effects, the most concerning being nephrotoxicity. MMF in combination with steroids and angiotensin-converting enzyme-inhibitor drugs is known to have some efficacy in the management of SRNS. These preliminary data have prompted the National Institutes of Health to sponsor a multicentric controlled trial to compare the safety and efficacy of MMF with that of CSA in the treatment of steroid-resistant focal segmental glomerulosclerosis (FSGS). If MMF therapy is found to be efficacious, it would help obviate the need for CSA and its associated nephrotoxicity. Clearly, MMF has emerged as an important new therapeutic option for the treatment of childhood nephrotic syndrome and FSGS. Further data are required to assess those conditions most likely to respond.

Mycophenolate mofetil in children with steroid-dependent and/or frequently relapsing nephrotic syndrome

BACKGROUND

Mycophenolate mofetil (MMF) has emerged as a new agent for treatment of a variety of glomerular diseases. This study examines the safety and efficacy of MMF in treating pediatric patients with steroid-dependent (SD) and/or frequently relapsing (FR) nephrotic syndrome (NS).

METHODS

We retrospectively reviewed the medical records of 18 patients with SDNS and/or FRNS treated with MMF for at least 3 months. MMF was used in 11 patients with SDNS (n=10) and FRNS (n=1), including 7 males and 4 females.

RESULTS

Mean age at time of diagnosis of NS was 3.3 years (range, 1.1-8.5 years), and at the start of MMF 5.9 years (range, 2.9-10 years). Seven patients had a renal biopsy prior to starting MMF; all had mesangial proliferative glomerulonephritis. Mean follow-up after starting MMF was 12.2 months (range, 4-24 months). Mean MMF dose was 948 mg/m2/day (range, 500-1087 mg/m2/day). MMF resulted in improvement in 9 of 11 patients, with 8 patients weaned off steroids completely, with a reduction in the mean relapse rate from 4.7 relapses/patient/year (range, 2.4-6) before MMF to 1.05 relapses/patient/year (range, 0-4.5) after MMF therapy (P=0.0001). The relative risk for relapse before MMF was 4.7 (P=0.0002). None of the patients had significant adverse events or intolerance to MMFtherapy.

CONCLUSION

We conclude that MMF is a safe and effective option for treatment of children with SDNS and/or FRNS.

Mycophenolate mofetil in steroid/cyclosporine-dependent/resistant nephrotic syndrome

Attempts to minimize the effects of prolonged steroid use in steroid-dependent nephrotic syndrome (SDNS) and the need to overcome steroid resistance (SRNS) justifies immunosuppressant therapy. We report our experience in a cohort of patients with SD/SRNS during the administration of mycophenolate mofetil (MMF) in a prospective protocol initiated in January 2001. Twenty-six children with idiopathic nephrotic syndrome were included (21 steroid dependent and 5 steroid resistant), whose response did not change after sequential treatment with cyclophosphamide (CPM) and cyclosporine (CsA). Histopathologic patterns were: 11 minimal change disease (MCD), 1 diffuse mesangial proliferation (DMP), 13 focal segmental glomerulosclerosis (FSGS) and membranous 1 glomerulonephritis (MGN). The median age of onset of NS was 2.8 years (range 1.2-12.5), and treatment with MMF was performed at a median age of 11.4 years (range 5-17) with an initial dose of 600 mg/m(2)/12 h, adjusted to maintain levels of mycophenolic acid (MPA) at 2.5-5 mcg/ml. The planned duration of study to assess treatment efficacy was 6 months. The mean MMF dose required was 624 (SD=136) mg/m(2)/12 h (range 415-970), which maintained mean C(0)-MPA levels of 2.9 (SD=1.17) mcg/ml (range 1.2-5.9 mcg/ml). In the five patients with SRNS, only one achieved complete remission. In the patients with SDNS, steroid sparing was achieved in 15 and 9 remained in remission on MMF monotherapy. Withdrawal of MMF resulted in immediate relapse in 47%. In our study, MMF was a useful immunosuppressant due to its fewer undesirable effects and similar efficacy to other drugs used. It appears effective for the maintenance of remission in SDNS patients, with a response similar to that of CsA.

Effectiveness of high trough levels of cyclosporine for 5 months in a case of steroid-dependent nephrotic syndrome with severe steroid toxicity

Glucocorticoid treatment for steroid-dependent nephrotic syndrome (NS) is associated with severe adverse effects, such as bone fractures and epidural lipomatosis. Furthermore, a high trough level of cyclosporine (CsA) over an extended period of time is known to induce CsA nephropathy. We present a girl with steroid-dependent NS and steroid-induced vertebral compression fractures and epidural lipomatosis who was treated with a high-dose of prednisolone after experiencing several relapses. A high CsA trough level (between 147 and 225 ng/mL) over a period of only 5 months was effective in improving the vertebral compression fractures, alleviating the epidural lipomatosis by enabling the discontinuation of prednisolone treatment. Thus, high trough levels of CsA over a short period of time may enable prednisolone to be discontinued in cases of steroid-dependent NS without causing any clinical, histological, serum and/or urinary CsA-related adverse effects.

Cyclosporine therapy monitored with abbreviated area under curve in nephrotic syndrome

Cyclosporin A (CsA) is an effective therapy for children with long-lasting nephrotic syndrome (NS). Long-term treatment can result in chronic CsA nephropathy (CsAN) and there is controversy concerning its incidence and severity. Trough levels are commonly used to monitor the drug concentration. We report a retrospective clinical and histological analysis of 18 children (12 males, 6 females) with steroid-dependent nephrotic syndrome (15 patients) and partially steroid-sensitive nephrotic syndrome (3 patients) treated with CsA for a long-term period (mean 4.9 years, range 2.2-6.9). Before CsA treatment all patients had normal creatinine clearance. CsA was started at a dose of 5 mg/kg per day administered orally in two divided doses and adjusted to maintain the mean CsA blood concentration between 250 and 350 ng/ml obtained from abbreviated area under the curve (AUC). A renal biopsy was performed after a mean period of 3.9 years (range 2.2-6.2) from the start of CsA treatment. Tubular, interstitial, and arteriolar lesions were evaluated in order to assess CsAN. The mean CsA dose and the mean CsA blood concentration were 4.4 mg/kg per day (range 3.6-5.8) and 276.6 ng/ml (range 162-346), respectively. No child had a worsening creatinine clearance during CsA treatment and follow-up after CsA discontinuation. If compared with the year before the start of CsA treatment, NS relapses and prednisone (PDN) dose significantly decreased during CsA treatment, 4/year versus 0.8/year (P <0.0001) and 0.9 mg/kg per day versus 0.2 mg/kg per day (P <0.0001), respectively. Histological analysis showed 15 patients with minimal change disease and 3 with focal segmental glomerulosclerosis. Clear-cut lesions diagnostic of CsAN were never found and only mild lesions were observed in 5 children (suggestive of CsAN in 2 patients and consistent with CsAN in 3 patients). Long-term CsA treatment is confirmed to be effective in preventing NS relapses and reducing PDN dose. Renal function is not a reliable indicator of CsAN. With the mean CsA blood concentrations used in our patients CsAN presented a low incidence (28%) and was generally mild. Renal biopsy should be performed 2-3 years from the start of long-term CsA treatment, especially if the mean CsA blood concentrations are not regularly monitored.

Single-dose daily administration of cyclosporin A for relapsing nephrotic syndrome

Cyclosporin A (CsA) has been reported to be effective as a steroid-sparing agent in frequently relapsing nephrotic syndrome (FRNS). However, low efficacy has sometimes been observed in selected patients with steroid-dependent FRNS. We speculated that a low peak level of CsA in the blood might be the cause, and conducted a prospective pilot study on such steroid-dependent FRNS patients to examine whether single-dose daily administration of CsA would yield a sufficient peak blood level, and therefore a satisfactory steroid-sparing effect. Five children with steroid-dependent FRNS, aged 7-16 years, were enrolled in the study. All had been treated with prednisolone combined with twice daily CsA ( T), which was subsequently replaced with the single-dose daily administration protocol ( S), because of a poor steroid-sparing effect. Although the mean daily CsA dosage with the S protocol was significantly lower than with the T protocol ( S 2.4+/-1.1 mg/kg per day vs. T 3.6+/-0.8 mg/kg per day, P<0.05), the mean peak blood level tended to be higher with the S protocol than the T protocol ( S 764+/-122 ng/ml vs. T 358+/-250 ng/ml, P=0.1797) without mean trough blood level elevation. As a result, the minimum dose of prednisolone required for maintenance of clinical remission tended to be lower with the S than the T protocol ( S 0.4+/-0.2 mg/kg on alternate days vs. T 0.6+/-0.4 mg/kg on alternate days, P=0.0656). No evidence of CsA nephrotoxicity was observed in a repeat renal biopsy performed 9 months after commencement of the S protocol in one patient. These clinical observations, although on a small number of patients and preliminary, suggest that single-dose daily administration of CsA might be an attractive protocol in selected patients with steroid-dependent FRNS in whom CsA administration by the conventional protocol is associated with a poor steroid-sparing effect.

Effectiveness and safety of ciclosporin as therapy for autoimmune diseases of the liver in children and adolescents

BACKGROUND

Conventional treatment for autoimmune hepatitis results in a significant percentage of failures and several, poorly tolerated, side-effects. Therapy for autoimmune cholangitis and giant cell hepatitis associated with autoimmune haemolysis is poorly documented. Ciclosporin is a promising treatment for all of these diseases.

METHODS

We reviewed the records of 12 patients treated in our unit between 1987 and 2001. Eight had autoimmune hepatitis, two had autoimmune cholangitis and two had giant cell hepatitis. Indications for ciclosporin were treatment failure (four patients) and contraindications to/refusal of steroids (eight patients). Ciclosporin was administered in five untreated cases and in seven patients during relapse. The mean duration of ciclosporin administration was 35.6 months (8-89 months). The median follow-up was 6.5 years (1.5-15 years).

RESULTS

All patients achieved complete remission in a median period of 4.5 weeks (2-12 weeks). No treatment withdrawal due to side-effects occurred. Three patients required a combination of ciclosporin with conventional treatment due to severe liver function impairment. Tolerance to ciclosporin was excellent. A 20% transient elevation of serum creatinine occurred in one case, gingival hypertrophy in two and moderate hypertrichosis in two.

CONCLUSIONS

Ciclosporin may be considered as a safe treatment for all autoimmune liver diseases and as an effective alternative for front-line therapy.

Cyclosporin A for the treatment of severe Henoch-Schönlein glomerulonephritis

We evaluated the efficacy of cyclosporin A (CyA) for treating pediatric patients with severe Henoch-Schönlein glomerulonephritis (HSP-GN) and nephrotic-range proteinuria. Seven pediatric HSP-GN patients (5 boys, 2 girls) were treated with CyA, with a mean age of 10.6 years at diagnosis (range 7.2-15.2 years) and mean follow-up times of 6.0 years (range 4.4-8.9 years) from diagnosis and 5.2 years (range 3.4-7.7 years) from the beginning of the CyA treatment. All had developed nephrotic-range proteinuria within 1-3 months of the HSP diagnosis. A renal biopsy was performed on all the patients, and two showed rapidly progressive glomerulonephritis. They all received additional angiotensin converting enzyme inhibitor medication and one to three types of immunosuppressive treatment had been tried in five of the seven patients before CyA was initiated at a mean interval of 0.7 years after diagnosis (range 0.1-2.0 years). All the patients responded to the CyA treatment within a mean of 1.4 months (range 1 week to 4 months). Four patients achieved a stable remission and had been without CyA treatment for a mean of 3.7 years (range 2.9-5.3 years) by the end of the follow-up. Three patients seemed to become CyA dependent, since they developed proteinuria when the treatment was stopped. CyA treatment had been started significantly earlier ( P=0.045) in the former group (mean 0.2 years, range 0.1-0.3 years) than in the latter (mean 1.5 years, range 1.2-2.0 years). Renal function was preserved in all patients, the glomerular filtration rate, plasma cystatin C, serum albumin, and serum creatinine being within normal limits at the end of the follow-up. We conclude that CyA treatment for severe treatment-resistant HSP-GN is promising, since four of the seven patients enjoy stable remission and all have retained their renal function after a mean follow-up of 6.0 years. However, some patients seem to develop CyA-dependent nephritis.

Risk factors for cyclosporine-induced tubulointerstitial lesions in children with minimal change nephrotic syndrome

BACKGROUND

Cyclosporine (CsA) is effective for the treatment of children with steroid-dependent and -resistant nephrotic syndrome (NS), but it can result in chronic CsA nephrotoxicity including CsA-induced tubulointerstitial lesions. The factors responsible for the development of CsA-induced tubulointerstitial lesions are unknown.

METHODS

To identify the risk factors for the development of CsA-induced tubulointerstitial lesions in children with minimal change NS who had been treated with long-term moderate-dose CsA, we compared several clinical and laboratory factors of 37 patients with and without CsA-induced tubulointerstitial lesions by the Mann-Whitney U test, Fisher's exact test, and stepwise logistic-regression analysis.

RESULTS

Thirteen patients had CsA-induced tubulointerstitial lesions and 24 patients had none. Among clinical and laboratory factors, the duration of CsA treatment (P = 0.003) and the duration of heavy proteinuria during CsA treatment (P = 0.024) were related to the development of CsA-induced tubulointerstitial lesions as determined by the univariate analyses. Indeed, CsA-induced tubulointerstitial lesions were found in 2 of 18 (11%) patients who had been treated with CsA for less than 24 months, but in 11 of 19 patients (58%) who had been treated for more than 24 months (P = 0.005). They were also found in 4 of 23 patients (17%) who had heavy proteinuria for less than 30 days during CsA treatment, but in 9 of 14 patients (64%) who had heavy proteinuria for more than 30 days (P = 0.006). Stepwise logistic-regression analysis revealed that the duration of CsA treatment for more than 24 months (chi2 = 6.203, P = 0.013) and the duration of heavy proteinuria during CsA treatment for more than 30 days (chi2 = 5.871, P = 0.015) were independent risk factors for the development of CsA-induced tubulointerstitial lesions.

CONCLUSIONS

Duration of the CsA treatment and the duration of heavy proteinuria during CsA treatment were independent significant risk factors for the development of CsA-induced tubulointerstitial lesions in children with MCNS who had been treated with long-term moderate-dose CsA.

Immunohistochemical analysis of renin activity in chronic cyclosporine nephropathy in childhood nephrotic syndrome

Although the pivotal role of activation of the intrarenal renin-angiotensin system (RAS) has been demonstrated in the rat model of chronic cyclosporine (CyA) nephropathy, it is still unclear whether intrarenal RAS activation is responsible for chronic CyA nephropathy in humans. Therefore, the distribution of renin in formalin-fixed, paraffin-embedded renal biopsy specimens obtained from 26 children who had idiopathic nephrotic syndrome (NS) and who were treated with long-term moderate-dose CyA was examined with the use of immunohistochemistry with rabbit polyclonal anti-human renin antibody. Nineteen patients had steroid-dependent NS, and 7 had steroid-resistant NS. However, CyA treatment led all of the latter patients into complete remission. All of the patients underwent renal biopsies at the start and the end of CyA treatment. In the pre-CyA specimens, immunoreactivity to renin was detected mainly in those parts of arterioles within the anatomically well-defined juxtaglomerular apparatus. In the post-CyA specimens, it was also detected in those parts of the vessels upstream from the juxtaglomerular apparatus. Moreover, the ratio of the number of renin-positive cells to the number of glomeruli (histologic renin index) increased significantly with long-term CyA treatment (from 1.26+/-0.24 to 4.30+/-0.40, P<0.0001). Eleven of the post-CyA specimens showed mild or moderate CyA-associated arteriolopathy (CAA), whereas 15 showed no CAA. The histologic renin index was significantly higher in specimens with CAA than in those without CAA (5.16+/-0.59 versus 3.67+/-0.48, P = 0.031). Seven CAA-positive patients underwent repeat biopsies 6 to 12 mo after discontinuing the CyA. Their specimens showed an improvement in the CAA and significantly lower histologic renin index compared with the post-CyA (from 4.18+/-0.69 to 2.10+/-0.25, P = 0.018). Eleven of the post-CyA specimens showed mild to moderate interstitial fibrosis, and 15 showed no fibrosis. There was no significant difference in immunoreactivity to renin between the specimens with interstitial fibrosis and those without. However, patients with interstitial fibrosis had significantly longer periods of heavy proteinuria during CyA therapy, because of either steroid-resistant NS or frequent relapses of NS (83+/-18 versus 35+/-12 d, P = 0.030). These findings indicate that long-term CyA treatment for idiopathic NS in children may stimulate renin production in arterioles. They also suggest that CyA-stimulated intrarenal RAS activation is responsible for the development of CAA and that CyA-induced interstitial fibrosis is potentiated by long-term heavy proteinuria and is at least partly independent of CyA-stimulated intrarenal RAS activation.

Overview of new immunosuppressive therapies

This review covers the new immunosuppressive drugs that have appeared in the past 5 years. It begins with the newest formulation (Neoral, Sandoz Pharmaceuticals, East Hanover, NJ, USA) of the clinically "mature" drug cyclosporin A and then reviews the literature on tacrolimus, sirolimus, and mycophenolate mofetil. In each case, the emphasis is on the evolution of experience with the drug and on the questions that the drug poses for pediatricians considering the risk-benefit ratio of the drug in children.