Rituximab versus tacrolimus as corticosteroid-sparing therapy for children with steroid-dependent nephrotic syndrome: A systematic review and meta-analysis of randomized and nonrandomized controlled trials.

Objectives: Prolonged use of corticosteroids induced complicated course in children with steroid-dependent nephrotic syndrome (SDNS), and the use of tacrolimus, a first-line alternative calcineurin inhibitor (CNI) agent was related to some unwanted adverse effects. Rituximab, a second alternative treatment has been proven to reliably reduce the number of relapses within 12 months with minimal adverse effects. Materials and Methods: Our review follows Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. All the databases were derived from MEDLINE, Proquest, EBSCOhost, Wiley, and Google Scholar within the past 11 years. The risk of bias was evaluated using the Revised Cochrane Risk of Bias Tool for Randomized Trials (RoB 2) and Risk of Bias in Non-Randomized Studies of Interventions. Meta-analysis used Review Manager (version 5.4) with a random effect model to obtain a pooled mean difference (MD) and odds ratio with 95% confidence intervals (CIs). Results: Four studies were included based on our eligibility criteria, and only three were included in the quantitative analysis. Three studies had low and one study had a moderate risk of bias. Pooled data results indicated that Rituximab was superior to tacrolimus in reducing the number of patients with 1-2 relapses (MD = 0.44, [95% CI: 0.21-0.91]) and had higher eGFR values (MD = 6.67; [CI - 2.92-10.61]). However, Rituximab showed insignificant superiority compared to tacrolimus in reducing the number of patients with 3 relapses, sustained remission, cumulative steroid use, serum cholesterol, and serum albumin concentrations. Conclusion: Rituximab exhibits more advantages in treating SDNS compared to tacrolimus, although the treatment options are highly individualized. Both regimens must also be weighed against their potential side effects to achieve a better overall health status.

[Steroid-Dependent Nephrotic Syndrome Due to Minimal Change Glomerulonephritis Treated with Rituximab].

47-year-old woman suffering from minimal lesion glomerulonephritis previously undergone high-dose steroid therapy and subjected to exacerbations of nephrotic syndrome after therapy discontinuation. It was decided to initiate off-label treatment with Rituximab at a dosage of 375 mg/m2 administred at zero-time, one-month and three months with good therapeutic response and resolution of the clinical laboratory picture. The therapy was well tolerated and had no side effects. This scheme could be an alternative to the conventional therapeutic scheme with steroids or other classes of immunosuppressive drugs, especially in order to avoid problems related to prolonged exposure to steroid therapy.

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.

Association between the time of initial relapse and subsequent relapses in patients with childhood-onset idiopathic nephrotic syndrome.

BACKGROUND: Nephrotic syndrome relapse within 6 months is a known risk factor for steroid-dependent nephrotic syndrome/frequently relapsing nephrotic syndrome (SDNS/FRNS), but the risk of early development of SDNS/FRNS and initiation of immunosuppression therapy remains unknown. METHODS: Patients with childhood-onset idiopathic nephrotic syndrome who had the first relapse within 6 months were enrolled. We analyzed the relationship between the time of the first relapse or the time of initial remission and incidence of SDNS/FRNS or initiation of immunosuppression therapy. RESULTS: Forty-five patients were enrolled. Twenty out of 23 patients (87%) with the first relapse within 30 days after discontinuing initial steroid therapy experienced a second relapse within 30 days after discontinuing steroid therapy. Additionally, most patients in this group (96%) experienced a second relapse within 6 months after the onset and were diagnosed as SDNS/FRNS at this time. In this group, the incidence of SDNS/FRNS development within 6 months was 96%. In contrast, the incidence of SDNS/FRNS development within 6 months was 18% in patients with the first relapse more than 30 days after steroid discontinuation. The incidence of initiation of immunosuppressive agents within 6 months was 83% in the former group and 14% in the latter group. CONCLUSIONS: Most patients with the first relapse within 30 days after discontinuing steroid therapy developed SDNS/FRNS and were administered immunosuppressive agents within 6 months. Thus, it might be reasonable to start immunosuppression therapy in this group without waiting for the second relapse.

Adult survivors of childhood-onset steroid-dependent and steroid-resistant nephrotic syndrome treated with cyclosporine: a long-term single-center experience.

BACKGROUND: Although evidence has confirmed that cyclosporine (CS) is efficacious against childhood-onset steroid-dependent and steroid-resistant nephrotic syndrome (SD/SRNS), some patients may continue to relapse during adulthood. However, predictive factors for adult active disease and kidney complications, such as chronic kidney disease (CKD) and hypertension, in this cohort remain unknown. METHODS: We conducted a retrospective study on the long-term outcomes of 81 young adults with childhood-onset SD/SRNS treated with CS. The primary endpoint was the probability of active disease into adulthood. The secondary endpoint was the probability of developing kidney complications. RESULTS: At the last follow-up (median age, 23.2 years; median disease duration, 15.8 years), 44 adult patients (54%) continued to have active disease, whereas 16 patients developed CKD or hypertension, respectively. The proportion of patients developing kidney complications was similar between the active disease and long-term remission groups. Young age at NS onset and history of relapse during the initial CS (median, 31 months) were independent predictive factors for active disease. Acute kidney injury at NS onset, focal segmental glomerulosclerosis, and irreversible CS nephrotoxicity were identified as risk factors for the development of CKD, whereas older age was identified as a risk factor for the development of CKD and hypertension. CONCLUSIONS: More than 50% of adult survivors treated with CS continued to have active disease, and each 20% developed CKD or hypertension. A long-term follow-up is necessary for patients with SD/SRNS to identify the development of kidney complications later in adulthood that can be attributed to prior disease and CS treatment in childhood, irrespective of disease activity. A higher resolution version of the Graphical abstract is available as Supplementary information.

Review of the Role of Rituximab in the Management of Adult Minimal Change Disease and Immune-Mediated Focal and Segmental Glomerulosclerosis.

Background: Minimal change disease and primary FSGS are podocytopathies but are also immune-mediated diseases. Rituximab acts via multiple mechanisms by tilting the balance between autoreactive B and T cells in favor of regulatory B and T cells. The consequences are decreased production of cytokines, chemokines, and permeability factors by these cells. In the past decade, we have seen the discovery of autoantibodies mediating nephrotic syndrome (anti-annexin A2 antibody, anti-UCHL1 antibody, and anti-nephrin antibody), and rituximab decreases their production. Rituximab also binds to podocyte SMPDL3b and has direct podocyte actions. Summary: Rituximab's role in managing these primary podocytopathies has been discussed in this brief review. Rituximab has been used extensively in children and adults with frequently relapsing and steroid-dependent nephrotic syndrome. However, rituximab is not very promising in adult steroid-resistant nephrotic syndrome. Although ofatumumab would cause prolonged B-cell depletion and is fully humanized, it is unclear if it is superior to rituximab in preventing relapse of nephrotic syndrome. Key Messages: Rituximab therapy can induce prolonged remission in adults with frequently relapsing and steroid-dependent nephrotic syndrome. However, no good data exist on using rituximab in steroid-resistant nephrotic syndrome.

A successful treatment for chronic active Epstein-Barr virus disease with Nephrotic Syndrome.

Chronic active Epstein-Barr virus (CAEBV) disease is more likely to occur when a patient is on immunosuppressive therapy for any disease or is susceptible to infection, and the prognosis is poor without appropriate treatment, including hematopoietic stem cell transplantation (HSCT). In addition to HSCT, several other chemotherapy regimens have been reported, but all of them are difficult to maintain in remission. Without HSCT, survival rates have been reported to be 50% in 5 years and 25% in 15 years. This is a report of a 13-year-old boy who developed CAEBV disease during cyclosporine A (CyA) treatment for the steroid-dependent nephrotic syndrome (SDNS). Since SDNS precluded HSCT or chemotherapy, CyA was tapered off based on the belief that alleviating his immunosuppressed state would decrease the CAEBV disease. We decided to gradually reduce the CyA dose to activate T-cell immunity, while periodically monitoring the EBV viral load. Finally, we found an appropriate dose that could suppress both CAEBV disease and SDNS, and it lasted for more than 9 years. No case has been reported to date in which a patient developed CAEBV disease while receiving immunosuppressive drugs for the primary disease, and both diseases were controlled only by reducing the dose of immunosuppressive drugs. In this report, we show that dose reduction of immunosuppressive agents without chemotherapy or HSCT is an effective option for the treatment of CAEBV disease in patients receiving immunosuppressive agents.

Long-Term Efficacy and Safety of Rituximab Versus Tacrolimus in Children With Steroid Dependent Nephrotic Syndrome.

Introduction: In the Rituximab for Relapse Prevention in Nephrotic Syndrome (RITURNS) trial, we demonstrated superior efficacy of single-course rituximab over maintenance tacrolimus in preventing relapses in children with steroid dependent nephrotic syndrome (SDNS) during a 1-year observation. Here we present the long-term outcomes of all 117 trial completers, who were followed up for another 2 years. Methods: Relapsing patients in the rituximab arm received a second course of rituximab, either with (n = 44) or without mycophenolate mofetil (MMF) cotreatment (n = 15). In the tacrolimus arm, second line rituximab monotherapy was initiated after relapses (n = 32) or electively (n = 24). Results: All 12-month relapse-free patients in the rituximab arm relapsed in the second postexposure year, resulting in similar median relapse-free survival times in the 2 trial arms (62 vs. 59 weeks). Second line rituximab in the tacrolimus arm was less effective than first-line therapy in patients switched to rituximab following a relapse (relapse-free survival 55 vs. 63 weeks, P < 0.01). B-cell counts 6 months post-rituximab predicted relapse risk both for first and second line therapy. MMF cotreatment yielded much improved 2-year relapse-free survival as compared to rituximab monotherapy (67% vs. 9%, P < 0.0001). Higher grade 2 adverse event rates were observed post-rituximab versus on tacrolimus (0.87 vs. 0.53 per year). Conclusion: The superior therapeutic effect of rituximab in SDNS vanishes during the second year post-exposure. Rituximab appears to yield longer remission when applied as first line as compared to second line therapy. Maintenance MMF following rituximab induces long-term disease remission.

Predictive factors of long-term disease remission after rituximab administration in patients with childhood-onset complicated steroid-dependent nephrotic syndrome: a single-center retrospective study.

BACKGROUND: Despite the fact that rituximab (RTX)-associated adverse events may be relatively frequent in younger patients, recent studies have reported RTX as a suitable first-line steroid-sparing agent for maintaining remission in children with steroid-dependent nephrotic syndrome (SDNS). However, the impact of age at RTX initiation on the long-term outcome remains unknown in this cohort. METHODS: We retrospectively reviewed the clinical course of 61 patients with complicated SDNS who received a single dose of RTX (375 mg/m2) followed by maintenance immunosuppressive agents (IS) from January 2008 to March 2021. In patients who achieved > 12 months of prednisolone-free remission, IS tapering within 6 months was tried to achieve. The primary endpoint was the probability of achieving long-term treatment-free remission at the last follow-up. RESULTS: After RTX initiation, 52 patients (85.2%) relapsed after a median of 665 days, and 44 patients (72.1%) received additional RTX doses (total, 226 infusions). At the last follow-up (median observation period, 8.3 years; median age, 18.3 years), 16 patients (26.2%) achieved long-term remission. Multivariate analysis showed that older age at RTX initiation was the independent predictive factor for achieving long-term remission (odds ratio, 1.25; p < 0.05). The proportion of those who achieved long-term remission was significantly higher in patients aged ≥ 13.5 years than in those aged < 13.5 years at RTX initiation (52.6 vs 14.3%, p < 0.05). Persistent severe hypogammaglobulinemia did not develop in older children (≥ 13.5 years) at RTX initiation. CONCLUSION: For older children with complicated SDNS, RTX appeared to be a suitable disease-modifying therapy without persistent adverse events.

Rituximab therapy in adults with steroid-dependent nephrotic syndrome.

Introduction: Patients with steroid-dependent nephrotic syndrome (SDNS) suffer frequent relapse with adverse effects caused by long-term prednisolone treatment. Recently, the chimeric monoclonal antibody against the protein CD20 (rituximab - RTX) was observed to be efficacious and safe in the treatment of patients with SDNS. We summarized the scientific literature to evaluate RTX therapy in the clinical management of SDNS. Material and methods: PubMed, EMBASE, and Cochrane Library databases were investigated from interception to 2019-6-6, without language limitation. The analysis was restricted to adults ≥ 19 years of age. Data were administered and analyzed through the Review manager 5.3 software. Results: After RTX treatment, relapse times, prednisolone dose, and proteinuria decreased, whereas serum albumin was increased. The clinical parameters blood pressure and total cholesterol diminished also, whereas bone mineral density was improved. Overall, RTX ameliorated the adverse effects of prednisolone. Moreover, the Th1/Th2 ratio was changed except for the CD19 and CD20 cell counts. Additionally, most of the adverse effects of RTX were mild and well tolerated. Conclusions: In the studies that we considered, we concluded that RTX treatment was effective and safe in the therapy of patients with SDNS. Nevertheless, more randomized controlled trials are required to explore the mechanism of RTX action and verify its efficacy.

Incidence of relapse and frequently relapsing/steroid-dependent nephrotic syndrome in Chinese children with steroid-sensitive nephrotic syndrome: A cohort study.

AIM: This study aimed to investigate the incidence of relapse and FR/SDNS in Chinese children with SSNS and to develop clinical prediction models for relapse and FR/SDNS. METHODS: This retrospective cohort study involved 339 newly onset SSNS patients between 2006 and 2016. The incidence of relapse and FR/SDNS were estimated using the Kaplan-Meier method. Prediction models were constructed based on Cox proportional-hazards regression. RESULTS: The median follow-up time was 8.7 years. The cumulative incidence of relapse at 1-, 2-, and 5-year was 51.0%, 62.5%, and 66.6%. The cumulative incidence of FR/SDNS at 1-, 2-, and 5-year was 18.4%, 29.0%, and 32.9%. The final prediction model for first relapse included four variables (serum albumin, triglycerides, IgM, and time to first remission). The model's discriminative ability was low (Harrell's C index = 0.62). The final prediction model for FR/SDNS included four variables (serum albumin, lipoprotein(a), time to first remission, and time to first relapse). The discrimination and calibration of the prediction model for FR/SDNS were acceptable (Harrell's C index = 0.73, Brier score at 1- and 2-year were 0.11 and 0.17). CONCLUSION: The first relapse and FR/SDNS mainly occurred in the first 2 years after initial SSNS onset. The prediction model for relapse developed using common clinical parameters performed poorly, while the prediction model for FR/SDNS might be useful.

Immunophenotypic Alterations in Adult Patients with Steroid-Dependent and Frequently Relapsing Nephrotic Syndrome.

Immune dysregulation plays a key role in the pathogenesis of steroid-dependent/frequently relapsing nephrotic syndrome (SDNS/FRNS). However, in contrast with evidence from the pediatric series, no major B- or T-cell alterations have been described for adults. In these patients, treatment with rituximab allows safe discontinuation of steroids, but long-term efficacy is variable, and some patients experience NS relapses after B cell reconstitution. In this study, we aimed to determine disease-associated changes in the B and T cell phenotype of adult patients with SDND/FRNS after steroid-induced remission. We also investigated whether any of these changes in immune cell subsets could discriminate between patients who developed NS relapses after steroid-sparing treatment with rituximab from those who did not. Lymphocyte subsets in SDNS/FRNS patients (n = 18) were compared to those from patients with steroid-resistant NS (SRNS, n = 7) and healthy volunteers (HV, n = 15). Before rituximab, SDND/FRNS patients showed increased frequencies of total and memory B cells, mainly with a CD38-negative phenotype. Within the T-cell compartment, significantly lower levels of FOXP3+ regulatory T cells (Tregs) were found, mostly due to a reduction in CD45RO+ memory Tregs compared to both SRNS and HV. The levels of CD45RO+ Tregs were significantly lower at baseline in patients who relapsed after rituximab (n = 9) compared to patients who did not (n = 9). In conclusion, patients with SDND/FRNS displayed expansion of memory B cells and reduced memory Tregs. Treg levels at baseline may help identify patients who will achieve sustained remission following rituximab infusion from those who will experience NS relapses.

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.

Pioglitazone enhances proteinuria reduction in complicated pediatric nephrotic syndrome.

BACKGROUND: Nephrotic syndrome (NS) is a common pediatric kidney disease, yet current treatments for complicated NS are only partially effective and have significant toxicity. There is no Food and Drug Administration (FDA)- or European Medicines Agency (EMA)-approved safe and effective treatment for NS. Thiazolidinediones (TZDs) have been shown to reduce proteinuria in both diabetic and non-diabetic kidney disease and in preclinical studies to directly protect podocytes from injury and reduce proteinuria. Here, we report on the potential utility of the addition of the TZD pioglitazone (PIO) to enhance proteinuria reduction in 8 children and young adults with steroid dependent NS and steroid resistant NS. METHODS: Clinical data were analyzed in comparable time periods before and after the addition of PIO to their medical regimens. Eight NS patients with minimal change NS (n = 2), focal segmental glomerulosclerosis (FSGS) (n = 4), or collapsing FSGS (n = 2) were evaluated. RESULTS: Prior to PIO initiation, all children and young adults had already received multiple immunosuppressive medications (mean = 3.75). Five of eight patients (63%; "Responders") had notable proteinuria reduction within 1 month of PIO initiation (62% reduction; P = 0.04) and normalization within 6 months (97% reduction; P = 0.04). PIO-related benefits among the responders included notable increases in serum albumin (2.5 to 3.7 g/dl; P = 0.08), dramatic reductions in hospitalizations for IV albumin infusions and diuresis (11 to 0; P < 0.01), and considerable reduction in total immunosuppression (43% reduction; P > 0.1). Importantly, no patients experienced any adverse events attributable to PIO during a total of 136 patient-months of treatment. CONCLUSIONS: While confirmatory safety and efficacy studies are needed, these findings suggest pioglitazone (a non-immunosuppressive drug) may be useful to enhance proteinuria reduction in some children and young adults with complicated NS. A higher resolution version of the Graphical abstract is available as Supplementary information.

Persistent SARS-CoV-2 Infection in a Patient with Nephrotic Syndrome under Rituximab Therapy: Successful Treatment with a Combination of Remdesivir and Monoclonal Antibodies.

Rituximab is an effective treatment for frequently relapsing/steroid-dependent nephrotic syndrome, but there is concern about infections caused by humoral immunodeficiency. We herein report a case of prolonged (>7 weeks) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A 24-year-old man with minimal change disease treated with rituximab developed SARS-CoV-2 infection. The clinical response to remdesivir was soon transiently abolished. Treatment with casirivimab and imdevimab (REGEN-COV) monoclonal antibodies in combination with remdesivir resulted in complete clearance of the infection. The REGEN-COV antibody cocktail may improve the outcome of SARS-CoV-2 infection in patients with humoral immunodeficiency.

Associations Between Cessation of Second-Line Therapies and Relapse Rates of Childhood Refractory Minimal-Change Nephrotic Syndrome: A Single-Center, Retrospective Chart Review.

Background: Most patients (≥85%) with minimal-change nephrotic syndrome (MCNS) respond to corticosteroid treatment. However, about 10% to 20% of patients with MCNS have steroid-resistant nephrotic syndrome and 25% to 43% of patients have steroid-dependent nephrotic syndrome or frequent-relapse steroid-sensitive nephrotic syndrome. Patients with refractory MCNS are treated with various second-line therapies. Objectives: This study aimed to evaluate the associations between the use of various second-line therapies and relapse rates in Chinese patients with childhood refractory MCNS. Methods: In this study, patients with childhood nephrotic syndrome renal biopsy proved to be "minimal change" from a single tertiary-care center between January 2002 and July 2018 were identified. A Total of 56 medical charts of patients treated with 1 of these second-line immunosuppressors: cyclophosphamide (CYC), mycophenolate mofetil (MMF), or tacrolimus (TAC) were reviewed. Patients were divided into CYC (n = 24), MMF (n = 20), and TAC (n = 12) groups according to the second-line therapy administered. Baseline characteristics, immune status, immunocomplex deposition in the renal tissue, and treatment outcomes were analyzed. Results: The ratio of patients with steroid-resistant nephrotic syndrome and steroid-dependent nephrotic syndrome in the CYC, MMF, and TAC groups did not differ significantly (P = 0.721). The immunofluorescence assay did not show any significant differences in immunocomplex deposition identified in renal biopsy specimens among the 3 groups. The rate of steroid-free remission in the TAC group (75%) was higher than that in the MMF (55%) and CYC (25%) groups (P = 0.012). At the last follow-up, two-thirds of children in the TAC group had a relapse following discontinuation of therapy. In the TAC group, patients for whom steroids were withdrawn had significantly higher levels of immunoglobulin G at the onset of nephrotic syndrome than those for whom steroids were continued (P = 0.017). In the MMF group, children with relapse had a significantly higher percentage of CD16+CD56+-positive cells than those without relapse (P = 0.042). The relapse rate after treatment discontinuation was significantly different among the 3 groups (P = 0.035). Notably, the relapse rate after treatment discontinuation in the CYC group was lower than those in the other 2 groups (P = 0.035). Conclusions: In this small population of Chinese patients with childhood refractory MCNS, the relapse rate following TAC therapy was higher than that following MMF or CYC therapy. Different proportions of CD16+CD56+-positive cells might be associated with relapse rates in patients with MCNS receiving MMF treatment. (Curr Ther Res Clin Exp. 2022; 83:XXX-XXX).

Rituximab-induced serum sickness in a girl with nephrotic syndrome.

Rituximab (RTX) has been used to treat B cell lineage lymphoma/leukemia or autoimmune or autoinflammatory disorders. RTX therapy has been extensively applied to cases of frequently relapsing nephrotic syndrome (FRNS) and steroid-dependent nephrotic syndrome. Rituximab-induced serum sickness (RISS) has been recognized as a rare severe type-3 hypersensitivity reaction in patients treated with RTX. We herein report a 10-year-old girl with RISS in FRNS. She was diagnosed with RISS based on characteristic symptoms, such as a fever, rash, arthritis, or proteinuria, during RTX therapy associated with a high level of human anti-chimeric antibody. Even after recovering from acute symptoms by RISS, she suffered from worsening relapses of nephrotic syndrome. The symptoms of RISS are non-specific, resembling viral infections, autoinflammatory diseases and Kawasaki disease, especially in children. While RISS is a rare complication among patients with nephrotic syndrome, it should be carefully considered as a severe complication in patients being treated with RTX.

Clinical efficacy of mycophenolate mofetil versus levamisole therapy in frequently relapsing and steroid dependent childhood nephrotic syndrome - A retrospective comparative analysis.

BACKGROUND: Children with frequently relapsing (FR) or steroid dependent (SD) nephrotic syndrome (NS) often develop side effects of corticosteroids. Various steroid-sparing agents are in practice, but only a few studies exist so far which have compared the safety and efficacy of these two commonly used agents. METHODS: We did a retrospective medical records review of children with FRNS or SDNS who had levamisole or mycophenolate mofetil (MMF) as a steroid-sparing agent with a minimum follow-up period of 12 months. The aim was to compare the course of our patients on MMF and levamisole. Our primary objective was to determine the number of children in sustained remission and those with the infrequently relapsing course on levamisole and MMF and, the median time to relapse in months in the two groups. The secondary objective was to compare time to first relapse and number of relapses in FRNS and SDNS group children on MMF and levamisole. RESULTS: A total of 88 children (34% female) with diagnosis FR/SDNS (44 each) were included in the study. Thirty-nine patients took levamisole, while 49 received MMF therapy. The median age of presentation at the relapsing course was 4.2 years. The proportion of children with sustained remission or infrequent relapsing (IFR) course on MMF was 73.6%, compared to 48.71% on levamisole (p-value .015). In addition, the median time to first relapse was 12 months (24, 1.5) and 4.5 months (24, 1) on respective medications. CONCLUSION: Clinical outcome was superior in the MMF group than levamisole, especially in SDNS patients, and also MMF was more efficacious in maintaining sustained remission.