Long-term follow-up after cyclophosphamide and cyclosporine-A therapy in steroid-dependent and -resistant nephrotic syndrome

Immunosuppressive agents for frequently relapsing/steroid-dependent nephrotic syndrome in children: a systematic review and network meta-analysis

Aim

This study aimed to systematically compare the efficacy of various immunosuppressive agents in treating pediatric frequently relapsing or steroid-dependent nephrotic syndrome (FRSDNS).

Methods

We conducted systematic searches of PubMed, Embase, the Cochrane Library, and the Web of Science up to May 23, 2023. Outcome measures included relapses within 1 year, mean cumulative exposure to corticosteroids, patients with treatment failure at 1 year, relapse-free survival during 1 year, and adverse events. The quality of the included studies was evaluated using the modified Jadad scale, the Methodological Index for Non-Randomized Studies (MINORS), and the modified Newcastle-Ottawa Scale (NOS).

Results

Rituximab was found to be the most likely (92.44%) to be associated with the fewest relapses within 1 year and was also most likely (99.99%) to result in the lowest mean cumulative exposure to corticosteroids. Rituximab had the highest likelihood (45.98%) of being associated with the smallest number of patients experiencing treatment failure at 1 year. CsA was most likely (57.93%) to achieve the highest relapse-free survival during 1 year, followed by tacrolimus (26.47%) and rituximab (30.48%). Rituximab showed no association with serious side effects and had comparable adverse effects to ofatumumab and tacrolimus.

Conclusion

Rituximab may be the most favorable immunosuppressive agent for treating pediatric FRSDNS. Nephrologists should consider this drug, along with their clinical experience, patient characteristics, and cost considerations, when choosing a treatment approach.

Biologics in steroid resistant nephrotic syndrome in childhood: review and new hypothesis-driven treatment

Nephrotic syndrome affects about 2-7 per 100,000 children yearly and accounts for less than 15% of end stage kidney disease. Steroids still represent the cornerstone of therapy achieving remission in 75-90% of the cases The remaining part result as steroid resistant nephrotic syndrome, characterized by the elevated risk of developing end stage kidney disease and frequently presenting disease recurrence in case of kidney transplant. The pathogenesis of nephrotic syndrome is still far to be elucidated, however, efficacy of immune treatments provided the basis to suggest the involvement of the immune system in the pathogenesis of the disease. Based on these substrates, more immune drugs, further than steroids, were administered in steroid resistant nephrotic syndrome, such as antiproliferative and alkylating agents or calcineurin inhibitors. However, such treatments failed in inducing a sustained remission. In last two decades, the developments of monoclonal antibodies, including the anti-CD20 rituximab and inhibitor of B7-1 abatacept, represented a valid opportunity of treatment. However, also the effectiveness of biologics resulted limited. We here propose a new hypothesis-driven treatment based on the combining administration of rituximab with the anti-CD38 monoclonal antibody daratumumab (NCT05704400), sustained by the hypothesis to target the entire B-cells subtypes pool, including the long-lived plasmacells.

Analysis and Study on Epidemiological Features and Prognosis of Nephrotic Syndrome in Xinjiang and Heilongjiang

Backgrounds

The pathogenesis of nephrotic syndrome (NS) is complex, and there are differences between regions. This study attempted to collect clinicopathological data of patients diagnosed with NS in Xinjiang and Heilongjiang in the past 2 years, so as to explore the onset features of NS and treatment and prognosis of patients in the two regions.

Methods

Clinical data of 375 patients diagnosed with NS using renal biopsy in Xinjiang and Heilongjiang from March 2019 to March 2021 were collected. Clinical data of patients before treatment were collected, and the chi-square test was utilized to compare the differences in the sex distribution of two groups. The U test was utilized to compare abnormal distribution continuous data between two groups, such as age, hemoglobin, plasma albumin, proteinuria, and triglycerides. Independent sample t-test was utilized to compare normal distribution continuous data between two groups, such as serum total protein, serum creatinine, blood urea nitrogen, glomerular filtration rate, and total cholesterol. The independent sample t-test was also used to compare the immunoglobulin levels and complement levels between the two groups after treatment, including IgA, IgG, IgM, C3, and C4. Kaplan-Meier method was used to analyze and plot the cumulative curves of complete remission rate and partial remission rate.

Results

For 275 NS patients from Xinjiang, the male-to-female ratio was 0.81 : 1. For 84 patients from Heilongjiang, the male-to-female ratio was 1.05 : 1. The onset ages of patients in Xinjiang and Heilongjiang were 22-45 years old and 22-47 years old, respectively. Respectively, there were 221 cases (80.36%) and 66 cases (78.57%) of primary NS in Xinjiang and Heilongjiang. There were 54 cases (19.64%) and 18 cases (21.43%) of secondary NS in Xinjiang and Heilongjiang, respectively. There was no statistically significant difference in cause distribution between the two regions (p = 0.756). After treatment, immunoglobulin levels (IgA (p = 0.009), IgG (p = 0.002), IgM (p < 0.001)) and complement C3 (p < 0.001) and C4 (p < 0.001) levels in Xinjiang and Heilongjiang were statistically significant. 129 cases in Xinjiang (46.91%) and 55 cases in Heilongjiang (65.48%) were treated with glucocorticoid (GC) combined with immunosuppressive therapy, respectively. After receiving treatment, 67 (24.36%) of 275 patients in Xinjiang achieved complete remission, 166 (60.36%) achieved partial remission, 22 (26.19%) of 84 patients in Heilongjiang achieved complete remission, and 56 (66.67%) achieved partial remission, and there was no statistically significant difference in remission rate between the two regions (p = 0.159). Patients in Xinjiang and Heilongjiang achieved complete remission at an average of 10.34 weeks (9.98-10.70) and 9.95 weeks (9.26-10.65), respectively. There was no significant difference in complete remission rates between the two regions (p = 0.663). Patients in Xinjiang and Heilongjiang achieved partial remission at an average of 8.76 weeks (8.38-9.14) and 7.99 weeks (7.33-8.65), respectively. There was no significant difference in the partial remission rate between the two regions (p = 0.065).

Conclusion

The causes of NS in Xinjiang and Heilongjiang were similar. After treatment, there were differences in immunoglobulin levels (IgA, IgG, IgM) and complement levels (C3, C4) in the two regions. The main treatment methods used in the two regions were GC combined with immunosuppressive therapy. The prognosis of patients in the two regions was similar. The complete remission rate and partial remission rate after treatment in the two regions were similar, and the average time required to achieve complete remission and partial remission was also similar.

Oral cyclophosphamide therapy in 100 children with steroid-sensitive nephrotic syndrome: experience from a developing country

BACKGROUND

Oral cyclophosphamide (CYP) is an important therapeutic agent in treatment of steroid-sensitive nephrotic syndrome having a steroid-dependent (SD) or frequent relapsing (FR) course. This retrospective observational study aimed to determine response to oral CYP and factors associated with positive response in these patients.

METHODS

We studied 100 children (male; 75) with FR (19%) and SD (81%) NS treated with CYP in the Pediatric Nephrology clinic. Responders were defined as children in whom steroids were stopped for at least 6 months following CYP and factors affecting response were analysed. Relapse-free survival was estimated by Kaplan-Meier method.

RESULTS

Median age at onset of NS was 3 years (IQR 2-5.2). Median age at CYP was 5.7 years (IQR 3.7-7.9). Fifty percent of patients were in the responder group at 6 months of CYP. Relapse-free survival post CYP therapy was 31% at 1 year, 11% at 2 years. Factors predicting good response were age at onset of NS > 3 years with 61.2% response at 6 months (p = 0.028) and older age at CYP initiation (> 5 years) with 61% response (p = 0.008). Multivariate regression analysis showed age at start of CYP > 5 years was an independent factor for good response (p = 0.044, OR = 2.903, CI -1.03 to 8.18).

CONCLUSIONS

Judicious selection of patients, especially with age of onset of NS more than 3 years and initiation of CYP after age of 5 years, can predict better response in this group of patents.

CD80 Insights as Therapeutic Target in the Current and Future Treatment Options of Frequent-Relapse Minimal Change Disease

Minimal change disease (MCD) is the most common cause of idiopathic nephrotic syndrome in children, and it is well known for its multifactorial causes which are the manifestation of the disease. Proteinuria is an early consequence of podocyte injury and a typical sign of kidney disease. Steroid-sensitive patients react well with glucocorticoids, but there is a high chance of multiple relapses. CD80, also known as B7-1, is generally expressed on antigen-presenting cells (APCs) in steroid-sensitive MCD patients. Various glomerular disease models associated with proteinuria demonstrated that the detection of CD80 with the increase of urinary CD80 was strongly associated closely with frequent-relapse MCD patients. The role of CD80 in MCD became controversial because one contradicts finding. This review covers the treatment alternatives for MCD with the insight of CD80 as a potential therapeutic target. The promising effectiveness of CD20 (rituximab) antibody and CD80 inhibitor (abatacept) encourages further investigation of CD80 as a therapeutic target in frequent-relapse MCD patients. Therapeutic-based antibody towards CD80 (galiximab) had never been investigated in MCD or any kidney-related disease; hence, the role of CD80 is still undetermined. A new therapeutic approach towards MCD is essential to provide broader effective treatment options besides the general immunosuppressive agents with gruesome adverse effects.

Multicenter analysis of the efficacy and safety of a non-standard immunosuppressive therapy with rituximab in children with steroid-resistant nephrotic syndrome

The aim of the study was a multicenter analysis of the efficacy and safety of a non-standard immunosuppressive therapy with rituximab (Rtx) in children with steroid-resistant nephrotic syndrome (SRNS) with particular emphasis on the possibility of permanent discontinuation or dose reduction of other immunosuppressive drugs such as glucocorticoids and cyclosporine A after 6 months of observation. The study group consisted of 30 children with idiopathic nephrotic syndrome, who were unresponsive to standard immunosuppressive treatment, and hospitalized in the years 2010-2017 in eight paediatric nephrology centres in Poland. The children were administered a single initial infusion of rituximab at the dose of 375 mg/m² of the body surface area. Proteinuria, the daily supply of glucocorticoids, and cyclosporine were assessed at the moment of the start of the treatment and after 6 months since its commencement. Before Rtx therapy, complete remission was found in 13 patients (43%) and partial remission was found in 8 patients (26%). These numbers increased to 16 (53%) and 12 (40%), respectively. At the start of the treatment 23 patients (76.6%) were treated with cyclosporine A. After 6 months, this number decreased to 15 patients (35%). At the start of the treatment, 18 patients (60%) were treated with prednisone. After 6 months, this number decreased to 8 patients (44%). Children with SRNS may potentially benefit from Rtx treatment despite relative risk of side effects. The benefits may include reduction of proteinuria or reduction of other immunosuppressants.

Cyclophosphamide versus cyclosporine A therapy in steroid-resistant nephrotic syndrome: a retrospective study with a mean 5-year follow-up

Objective

To compare the clinical efficacy of cyclophosphamide (CTX) and cyclosporine A (CSA) in initial treatment of children with steroid-resistant nephrotic syndrome (SRNS).

Methods

Prospectively maintained databases were reviewed to retrospectively compare two cohorts with SRNS that received peroral administration of 2 to 2.5 mg/kg/d CTX for 3 to 6 months or 1 to 5 mg/kg/d CSA for 2 years until the primary analysis cut-off date during 2007 to 2011. The time to first on-study relapse of SRNS was the primary endpoint. The effective rate was the second endpoint.

Results

A total of 127 children with SRNS were included (CTX-treated cohort: n = 62; CSA-treated cohort: n = 65), with a mean 5-year follow-up. CTX-treated children showed a significantly delayed time to first on-study relapse of SRNS compared with CSA-treated children (hazard ratio 0.66, 95% confidence interval 0.32–1.75). The relapse rate (rate/year) in CTX-treated children (1.1 ± 0.1) at the 24-month follow-up was significantly higher than that with CSA (0.4 ± 0.2). This difference persisted until the final follow-up.

Conclusions

CSA is associated with a significantly lower relapse rate and significantly higher effective rate compared with CTX, especially in children with minimal change disease.

Inducible ATF3-NFAT axis aggravates podocyte injury

Abstract

Podocyte injury and loss contribute to proteinuria, glomerulosclerosis, and eventually kidney failure. Activating transcription factor 3 (ATF3) is a stress inducible transcription factor that is transiently expressed following stimulation. However, we show for the first time an induction of ATF3 in podocytes from patients with chronic kidney disease, including minimal change disease, focal segmental glomerulosclerosis, and diabetic nephropathy. The role of ATF3 induction in podocytes under chronic conditions is currently unknown. Compared with the control (C57 or BKS), ATF3 expression was elevated in animal model of proteinuria (LPS-treated C57 mice) and the model of diabetic nephropathy (db/db mice). Similarly, ATF3 was increased in high glucose (HG)-treated, lipopolysaccharide (LPS)-treated, or Ionomycin-treated podocytes in vitro. Overexpression of ATF3 increased podocyte apoptosis and decreased expression of podocin, the cell marker of podocyte; in contrast, ATF3–small interfering RNA knockdown reduced podocyte apoptosis and increased podocin expression. The translocation of ATF3 to the nucleus was increased upon stimulation. ATF3 directly modulates the regulation of NFATc1 gene promoter activity and alters the expression of Wnt6 and Fzd9, direct target genes of NFATc1 signaling. The ATF3 binding site of NFATc1 gene promoter is located at the region 671–775 base pairs upstream of the transcription start site. These results indicate a novel inducible axis of ATF3–NFAT in podocyte injury and loss.

Key messages

• The stress factor ATF3 is induced in podocytes from proteinuric patients, including diabetes.

• ATF3 increased podocyte apoptosis and injury.

• ATF3 directly modulates the regulation of NFATc1 gene promoter activity.

High-Dose Rituximab Ineffective for Focal Segmental Glomerulosclerosis: A Long-Term Observation Study

BACKGROUND

A beneficial effect of rituximab (RTX) on focal segmental glomerulosclerosis (FSGS) in pediatric patients or in transplant recipients has been reported in isolated cases. However, the use of RTX in adult patients with idiopathic FSGS needs further investigation.

METHODS

Eight patients who had biopsy-proven FSGS (63.9 ± 14.0, range 40-81 years, 4 women, 4 men) with major risk factors precluding corticosteroids or conventional immunosuppression were treated with a high dose of RTX (8 weekly doses of 375 mg/m2) and prospectively followed up for at least 2 years (29.1 ± 8.8 months, range 24-42 months).

RESULTS

RTX failed to improve proteinuria in 7 out of 8 patients, who had persistent nephrotic proteinuria. In one case, a rapidly deteriorating renal function was also observed. Only one patient showed an improvement in renal function and a remarkable reduction in proteinuria. There were no differences in clinical or laboratory characteristics or in the CD20 B lymphocyte count after RTX between the responder and the 7 nonresponder patients.

CONCLUSIONS

Only a minority (1 of 8) in our series of adult patients with FSGS showed positive effects of high doses of RTX. Future studies are warranted to investigate more promising therapeutic options in the management of FSGS.

New biologics in the treatment of rare glomerular diseases of childhood

Minimal change disease and focal segmental glomerulosclerosis are rare but important causes of end-stage kidney disease in children. Though their pathogenesis is still unclear, evidence of immune abnormalities provided the background for the use of immunosuppressive drugs, such as corticosteroids, calcineurin inhibitors, antiproliferative and alkylating agents. Unfortunately, these treatments fail to achieve a sustained remission in a significant portion of patients and are burdened by significant toxicities. Recent developments of new biologics, including anti-CD20 monoclonal antibodies rituximab and ofatumumab, offered the opportunity to selectively target immune cell subsets or activation pathways, leading to more effective and safer hypothesis-driven treatments.

Podocyte-actin dynamics in health and disease

Genetic studies of hereditary forms of nephrotic syndrome have identified several proteins that are involved in regulating the permselective properties of the glomerular filtration system. Further extensive research has elucidated the complex molecular basis of the glomerular filtration barrier and clearly established the pivotal role of podocytes in the pathophysiology of glomerular diseases. Podocyte architecture is centred on focal adhesions and slit diaphragms - multiprotein signalling hubs that regulate cell morphology and function. A highly interconnected actin cytoskeleton enables podocytes to adapt in order to accommodate environmental changes and maintain an intact glomerular filtration barrier. Actin-based endocytosis has now emerged as a regulator of podocyte integrity, providing an impetus for understanding the precise mechanisms that underlie the steady-state control of focal adhesion and slit diaphragm components. This Review outlines the role of actin dynamics and endocytosis in podocyte biology, and discusses how molecular heterogeneity in glomerular disorders could be exploited to deliver more rational therapeutic interventions, paving the way for targeted medicine in nephrology.

Macrophage migration inhibitory factor urinary excretion revisited – MIF a potent predictor of the immunosuppressive treatment outcomes in patients with proliferative primary glomerulonephritis

Background

Macrophage migration inhibitory factor (MIF) is a cytokine that shares many activities with other pro-inflammatory cytokines in primary glomerulonephritis (GN). This study assesses the influence of immunosuppressive treatment on serum and urine MIF in patients with proliferative (PGN) and non-proliferative (NPGN) glomerulonephritis, and evaluates the potential of MIF in predicting outcomes.

Methods

Eighty-four patients (45 males and 39 females) with primary GN were included. Urinary excretion of MIF (ng/mg of urinary creatinine) was measured both pre- and post-treatment with combined steroids and cyclophosphamide. After a 12-month follow-up, the patients were retrospectively divided into four subgroups: responders of proliferative GN (R-PGN), non-responders of proliferative GN (NR-PGN), responders of non-proliferative GN (R-NPGN) and non-responders of non-proliferative GN (NR-NPGN).

Results

The median pre-treatment urinary MIF values were higher in PGN than in NPGN (3.6 versus 2.2; ANOVA P = 0.039). The highest pre-treatment urinary excretion of MIF was observed in NR-PGN (median 6.1), which was significantly higher than other subgroups (ANOVA P < 0.05). The treatment significantly reduced MIF urinary excretion only in R-PGN (P < 0.01). In NR-PGN, pre- (5.9 ± 2.9 pg/mgCr) and post-treatment mean MIF excretion (4.9 ± 2.3 pg/mgCr) exceeded the calculated cut off value (3.3 pg/mgCr).

Conclusion

MIF urinary excretion appears to be a prognostic marker of therapy outcomes only in proliferative glomerulonephritis, in which lower urinary MIF may be linked with good prognosis, whereas a higher MIF urinary excretion value was a marker of unfavorable therapy outcomes. In Non-Responders, urinary MIF measurements may help to reconsider the choice of the immunosuppressive regimen at early stages of the treatment and act as an impulse to search for new therapeutic strategies.

Rituximab treatment for relapsing minimal change disease and focal segmental glomerulosclerosis: a systematic review

BACKGROUND

Minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) remain a therapeutic challenge, since steroids and other immunosuppressive agents exhibit an unfavorable adverse event spectrum. The aim of this review was to systematically summarize and analyze data from preexisting studies reporting the outcome of rituximab (RTX) treatment in these patients.

METHODS

Study data on adult patients with either steroid-dependent or frequently relapsing MCD/FSGS were identified by a PubMed and Embase search. The number of relapses was calculated and the use of immunosuppressive co-medication prior to and after RTX treatment was quantified.

RESULTS

We identified 14 studies including 86 patients with frequently relapsing and steroid-dependent MCD or FSGS. Treatment with RTX reduced the number of relapses per year from 1.3 (0-9) relapses prior to treatment compared to 0 (0-2) after therapy (p < 0.001). Proteinuria decreased from 2.43 (0-15) g/day to 0 (0-4.89) g/day (p < 0.001), while serum albumin increased from 2.9 (1.2-4.6) at baseline to 4.0 (1.8-5.09) g/l after RTX (p = 0.001). The use of immunosuppression used at the time of RTX administration was also reduced after RTX therapy (p < 0.001). Baseline serum albumin was lower (p = 0.018), whereas the number of immunosuppressants prior to RTX was higher (p = 0.018) in patients with relapse after RTX.

CONCLUSIONS

The published data suggest that RTX is effective in reducing the number of relapses and sparing immunosuppression in frequently relapsing and steroid-dependent nephrotic syndrome due to MCD and FSGS. These promising findings have to be confirmed in controlled and prospective studies.

S-Fas urinary excretion helps to predict the immunosuppressive treatment outcomes in patients with proliferative primary glomerulonephritis

Deregulation of soluble apoptosis stimulating fragment (sFas) plays an important role in glomerulonephritis (GN). The study assed the influence of immunosuppressive treatment on serum and urine sFas in patients with proliferative (PGN) and non-proliferative (NPGN) GN, and evaluated the potential of sFas measurements in predicting outcomes. Eighty-four patients with GN (45 males and 39 females) were included. Serum concentration (ng/mL) and urinary excretion (ng/mg of urinary creatinine) of sFas were measured before and after the treatment. After 12 months of therapy with steroids and cyclophosphamide, patients were divided into two subgroups according to the treatment results: Responders (R) and Non-Responders (NR). The sFas urinary excretion was reduced after treatment in both PGN and NPGN (from 17.12 ± 15 to 5.3 ± 4.2, P = 0.008 and from 10.11 ± 6.1 to 3.4 ± 3.0, P = 0.039; respectively) whereas the sFas serum concentration remained unchanged. In PGN, pre-treatment urinary sFas concentration was significantly lower in the Responders than in Non-Responders (2.3 ± 3.1 vs 19.4 ± 14.1, P = 0.003), and was lower still than in both R (P = 0.044) and NR (P = 0.042) subgroups with NPGN. The immunosuppressive treatment reduced sFas urinary excretion in proliferative and non-proliferative GN and results suggest that the lower urinary sFas may be linked with favorable therapy outcomes in patients with PGN.

Prospective 5-year follow-up of cyclosporine treatment in children with steroid-resistant nephrosis

BACKGROUND

Cyclosporine has improved remission rates in children with steroid-resistant nephrotic syndrome (SRNS). However, little prospective long-term follow-up data is available.

METHODS

We prospectively followed and analyzed 5-year outcomes of all 35 patients enrolled in our previous prospective multicenter trial with cyclosporine and steroids in children with SRNS. At enrollment, 23 cases were classified as minimal change (MC), five as diffuse mesangial proliferation (DMP), and seven as focal segmental glomerulosclerosis (FSGS).

RESULTS

Renal survival at 5 years (median 7.7 years) was 94.3 %. Patient status was complete remission (CR) in 31 (88.6 %) (MC/DMP, 25; FSGS, 6); partial remission in one (FSGS); and non-remission in three (MC/DMP), including chronic kidney disease and end-stage kidney disease in one each. Among 31 patients with CR, 22 (71.0 %) were receiving treatment with immunosuppressants at 5 years, including cyclosporine in 19, and seven of these 22 continued to show frequent relapse. Response to cyclosporine at 4 months predicted 5-year outcome in 31 of 35 patients.

CONCLUSIONS

Although SRNS treatment with cyclosporine provides high renal survival and remission rates, many children require ongoing immunosuppression. Management has advanced from the prevention of end-stage kidney disease to the long-term maintenance of remission and management of relapse after induction therapy.

Tacrolimus versus cyclophosphamide in steroid-dependent or steroid-resistant focal segmental glomerulosclerosis: a randomized controlled trial

BACKGROUND

The efficacy and safety of tacrolimus (TAC) and cyclophosphamide (CTX) were prospectively examined in steroid-dependent or steroid-resistant primary focal segmental glomerulosclerosis (FSGS).

METHODS

Patients with biopsy-proven FSGS were enrolled and randomly divided into two groups: CTX and TAC. Patients treated with CTX (0.5-0.75 g/m(2)·month, i.v.) received prednisone at 0.8 mg/kg·day, while patients treated with TAC (0.1 mg/kg·day) received prednisone at 0.5 mg/kg·day. The plasma concentration of TAC was monitored and maintained at 5-10 ng/ml. After a 6-month treatment the patients were evaluated. Patients with complete remission (CR) and partial remission (PR) continued the treatment for 12 months with the dose tapered, whereas the patients with no response were excluded from the study and underwent an alternative treatment.

RESULTS

A total of 33 patients were recruited and 27 completed the 12-month follow-up. The TAC-treated patients (n = 15) showed a quick remission. The initial remission time averaged 1.23 ± 0.21 versus 2.21 ± 0.77 months in the CTX group (n = 18), but no significant difference was achieved (p > 0.05). At 6 months, the two groups showed a similar outcome. Ten patients from each group showed remission (7 CR and 3 PR). At 12 months, the CTX group had 9 CR and 3 PR while the TAC group had 6 CR and 5 PR. Remission rates in TAC tended to be higher than that in CTX, but there was no difference. CTX patients had a high prevalence of infections (50.0 vs. 13.3% in TAC, p < 0.05). In contrast, TAC-treated patients showed a high incidence of hyperglycemia (26.7 vs. 0.0% in CTX, p < 0.05).

CONCLUSION

These results suggest that CTX and TAC had a similar efficacy in steroid-dependent and steroid-resistant FSGS as manifested by reduced proteinuria, improved serum albumin level and renal function.

Second-line options for refractory steroid-sensitive and -resistant nephrotic syndrome

Although initially, many children with idiopathic nephrotic syndrome respond to steroid therapy, a repeated course for patients with relapses often causes significant steroid toxicity. Patients with frequent relapses or steroid dependency thus require alternative treatment, and so far, cyclophosphamide or levamisole have been regarded as first-choice options, although the latter is no longer available in many countries. Data are accumulating that mycophenolic acid may be an alternative for these patients. Calcineurin inhibitors (cyclosporine A or tacrolimus) are usually effective and are often used after cytotoxic treatment, but long-term treatment is necessary, raising concerns regarding the accumulation of side effects. Still, some patients show a tendency to relapse even on this maintenance regimen and some even have a refractory course that creates a medical dilemma. For this situation, recent data have demonstrated an effect of monoclonal antibodies directed to B cells - rituximab, a drug that may also prove to be a therapeutic option in less complicated cases. Patients that do not respond to initial steroid treatment need genetic testing and a renal biopsy, since focal segmental glomerulosclerosis may be present. Treatment options include pulse methylprednisolone, often in addition to calcineurin inhibitors (mainly cyclosporine but also, recently, tacrolimus). Cyctotoxic treatment, especially intravenous cyclophosphamide, has been found to be effective in steroid-resistant nephrotic syndrome by some studies but is inferior to calcineurin inhibitors. In addition, mycophenolic acid and rituximab have been used in children with primary focal segmental glomerulosclerosis; however, response seems to be inferior in comparison with patients with steroid-sensitive nephrotic syndrome. Taken together, idiopathic nephrotic syndrome, including steroid-sensitive as well as steroid-resistant patients, is a potentially serious disorder. Although much progress has been made in recent years and a wide arsenal of immunological interventions is available, some patients have a treatment refractory course. Prospective studies or at least standardization of treatment for complicated cases is urgently needed.

Pharmacokinetics of cyclosporin--a microemulsion in children with idiopathic nephrotic syndrome

OBJECTIVE

We present a prospective study of a microemulsion of cyclosporin to treat idiopathic nephrotic syndrome in ten children with normal renal function who presented cyclosporin trough levels between 50 and 150 ng/ml and achieved complete remission with cyclosporin. To compare the pharmacokinetic parameters of cyclosporin in idiopathic nephrotic syndrome during remission and relapse of the nephrotic state.

METHOD

The pharmacokinetic profile of cyclosporin was evaluated with the 12-hour area under the time-concentration curve (auc0-12) using seven time-point samples. This procedure was performed on each patient during remission and relapse with the same cyclosporin dose in mg/kg/day. The 12-hour area under the time-concentration curve was calculated using the trapezoidal rule. All of the pharmacokinetic parameters and the resumed 4-hour area under the time-concentration curve were correlated with the 12-hour area under the time-concentration curve. ClinicalTrials.gov: NCT01616446.

RESULTS

There were no significant differences in any parameters of the pharmacokinetic of cyclosporin during remission and relapse, even when the data were normalized by dose. The best correlation with the 12-hour area under the time-concentration curve was the 4-hour area under the time-concentration curve on remission and relapse of the disease, followed by the 2-hour level after cyclosporin (c2) dosing in both disease states.

CONCLUSIONS

These data indicate that the same parameters used for cyclosporin therapeutic monitoring estimated during the nephrotic state can also be used during remission. Larger controlled studies are needed to confirm these findings.

Recurrent focal segmental glomerulosclerosis: a discrete clinical entity

Focal segmental glomerulosclerosis refers to a set of particular histopathologic lesions in which steroid-resistant podocyte injury leads to patchy adhesions between the glomerular tuft and Bowman's capsule, followed by progressive glomerulosclerosis and proteinuric renal failure. Because of the nonspecific nature of this lesion, it has been difficult to classify the various forms of primary nephrotic syndrome in children. However, with the recognition of hereditary FSGS caused by mutations podocyte slit diaphragm genes, it is increasingly clear that the steroid-resistant form of FSGS that recurs in the renal allografts (R-FSGS) constitutes a distinct clinical entity. Capitalizing on recent studies in which patients have been screened for slit diaphragm gene mutations, this review focuses on the natural history and pathogenesis of R-FSGS.

Mycophenolate mofetil (MMF) treatment efficacy in children with primary and secondary glomerulonephritis

INTRODUCTION

The aim of our study was to analyse the efficacy and safety of mycophenolate mofetil (MMF) as part of the complex immunosuppressive therapy in children with different types of primary and secondary glomerulonephritis, who were not eligible for the standard treatment routine suggested by evidence-based guidelines.

MATERIAL AND METHODS

The study group comprised 85 children with proteinuric glomerulopathies hospitalized between 2007 and 2010, who were non-responders to immunosuppressive therapy. The dose of MMF was established as 1 g/m(2)/24 h. Remission was defined as negative proteinuria in three consecutive urinalyses.

RESULTS

The patients were divided into 4 groups: idiopathic nephrotic syndrome (n = 35), primary glomerulonephritis (n = 15), auto-antibody associated glomerulonephritis (n = 20) and lupus nephropathy (LN, n = 15). Ten patients from the first group (29%) and 5 patients each from the second and third group (34% and 25% respectively) did not respond to MMF therapy. On the other hand, all the children diagnosed with LN have reached clinical and biochemical remission.

CONCLUSIONS

Alternative rescue MMF therapy should always be taken into consideration in proteinuric patients who are non-responders to steroids, cyclosporine A and cyclophosphamide in whom the initial glomerular filtration rate is higher than 60 ml/min/1.73m(2). It is recommended that MMF be administered as part of the standard treatment regimen in patients diagnosed with lupus nephropathy. In these groups of patients, the potent benefits of this therapy are higher than expected side-effects.

New therapies in steroid-sensitive and steroid-resistant idiopathic nephrotic syndrome

Although many children with idiopathic nephrotic syndrome (INS) respond initially to steroid therapy, repeated courses for patients with relapses often cause significant steroid toxicity. Patients with frequent relapses who develop steroid dependency thus require alternative treatment. The first such options have been considered to be cyclophosphamide or levamisole, although the latter is no longer available in many countries. There is also an increasing body of data indicating that mycophenolic acid (MPA) may be an alternative for these patients. Calcineurin inhibitors (cyclosporine A or tacrolimus) are usually effective and often used after cytotoxic treatment, but long-term treatment with these agents is necessary, raising concerns of a possible accumulation of side effects. Some patients show a tendency to relapse even on such maintenance regimens, and some even have a refractory course that creates a medical dilemma. For this situation, recent data indicate that monoclonal antibodies directed to B-cells (e.g. rituximab) may have some effect and that such drugs may also prove to be a therapeutic option in less complicated cases. Patients that do not respond to steroid treatment need genetic testing and a renal biopsy since focal segmental glomerulosclerosis (FSGS) may be present. Treatment options include pulse methylprednisolone, often in addition to calcineurin inhibitors, mainly in the form of cyclosporine, but tacrolimus has also come into recent favor. Some studies have found cytotoxic treatment, especially intravenous cyclophosphamide, to be effective in steroid resistant nephrotic syndrome, but it seems to be inferior to calcineurin inhibitors. MPA and rituximab have also been used in children with primary FSGS, but the response seems to be inferior to that in patients with steroid sensitive nephrotic syndrome. Taken together, INS in both steroid-sensitive and steroid-resistant patients is a potentially complicated disorder, and despite a wide arsenal of immunological interventions, some patients have a treatment refractory course. Prospective studies or at least standardized treatment for complicated cases is urgently needed.

Some optimal culture conditions for production of cyclosporin a by Fusarium roseum

A suitable chemically defined culture medium was selected and some optimal conditions for the production of the highly immunosuppressive compound, cyclosporin A (Cyc A) are reported. Medium of the following composition was favorable for the production of Cyc A by Fusarium roseum: glucose, 30; NaNO3, 2; KH2PO4, 1; MgSO4.7H2O, 0.5 and KCL, 0.5 (g/l). Maximum productivity of Cyc A was achieved at pH 6.0 when 50 ml of the fermentation medium/250 ml flask, inoculated with five fungal agar discs (6 mm, diameter) of 7-days old F. roseum culture after incubation at 30 ºC at 120 rpm for 7 days.

Acute, subacute and chronic effect of cyclosporin-A on mean arterial pressure of rats with severe spinal cord contusion

Cyclosporin-A (CsA) protects and regenerates the neural tissue after spinal cord (SC) injury. These beneficial effects are achieved when CsA is administered at a dose of 2.5mg/kg/12h during the first 2 days after lesion. In view of these observations, it is realistic to envision that, CsA could be tested in SC-clinical trials. Since CsA is a drug strongly related to hypertension, results imperative to evaluate experimentally the effect of the above CsA-dose regimen on blood pressure. For this purpose, one hundred and twenty adult rats were subjected (10 groups) or not (10 groups) to SC-injury. Five injured and five Sham-operated groups received CsA. The remaining groups received only vehicle. Mean arterial pressure (MAP) was recorded from these animals at acute (6 and 24h post surgery; p.s.), subacute (96h), or chronic (30 days) stages of injury. In the latter, the therapy (CsA or vehicle) was administered only during the first 2 days p.s. or daily during 30 days of follow-up. The results of this study showed that SC-injury by itself induces a significant decrease of MAP during the acute and subacute phases of injury. CsA therapy was able to reestablish MAP parameters to control values in these phases. Regardless the therapy, a reestablishment of MAP was observed in chronic stages. Only the daily administration of CsA induced a significant increase in MAP, however; such variation remained into the normal ranges of MAP for rats. The potential benefits offered by CsA support its usefulness after SC-injury.