Long-term outcome of mycophenolate mofetil after a single dose of rituximab in childhood-onset refractory idiopathic nephrotic syndrome.

Background: Maintenance therapy using immunosuppressive agents after rituximab can be effective for sustaining remission in childhood-onset refractory frequently relapsing nephrotic syndrome/steroid-dependent nephrotic syndrome (FRNS/SDNS). We evaluated the long-term outcome of mycophenolate mofetil (MMF) after rituximab.

Methods: We conducted a multicenter, retrospective cohort study of patients with childhood-onset refractory FRNS/SDNS who received MMF as maintenance therapy after a single dose of rituximab and were followed up ≥ 2 years at three pediatric renal centers.

Relationship between clinical and pathologic findings and the presence of genetic variants in patients with steroid-resistant nephrotic syndrome.

Background: Genetic analysis, crucial in determining treatment strategies for steroid-resistant nephrotic syndrome (SRNS), can be performed in limited facilities and requires a long time. Predicting the presence or absence of genetic variants by clinical and pathologic features is preferable.

Methods: In this multicenter, retrospective study, we compared the clinical or pathologic features between the patients with and without genetic variants in children with SRNS and evaluated the efficacy of immunosuppressive treatment and long-term kidney outcomes.

Successful living donor kidney transplantation in a 14-year-old boy with Fontan circulation.

We report successful living donor kidney transplantation (KT) in a 14-year-old boy with Fontan circulation. He was diagnosed with complete transposition of the great arteries (type 3) at birth. After Blalock-Taussig shunt placement, he developed acute kidney injury, which recovered to stage 4 chronic kidney disease.

Impact of organ dysfunction on outcomes in pediatric hypernatremia: a retrospective observational study.

Background: Hypernatremia is associated with increased mortality risk in pediatric patients. However, its impact on outcomes remains unclear. This study aimed to clarify the clinical backgrounds of contemporary children with hypernatremia and identify prognostic factors, including the impact of organ dysfunction on mortality.

Feasibility of peritoneal dialysis and survival outcomes following laparotomy in children with kidney failure: a single-center, retrospective, observational study in Japan.

Background: Children with kidney failure may have congenital or acquired gastrointestinal comorbidities requiring laparotomy, which can complicate the initiation/continuation of peritoneal dialysis (PD) because of peritoneal adhesions.

Methods: This retrospective observational study included patients younger than 18 years who initiated PD after laparotomy or underwent laparotomy after PD initiation between February 1, 2006, and July 31, 2024. The primary endpoint was post-laparotomy PD failure, and the secondary endpoint was death.

Differences in kidney prognosis between congenital and infantile nephrotic syndrome.

Background: More than half of patients with congenital nephrotic syndrome (CNS) or infantile nephrotic syndrome (infantile NS) have a monogenic aetiology. This study aimed to clarify differences in the clinical course, genetic background, and genotype-phenotype correlation between CNS and infantile NS.

Methods: We enrolled patients who were diagnosed with CNS or infantile NS and referred to our hospital for genetic analysis and investigated the clinical characteristics and genetic background of patients with identified causative genes.

Long-term need and potential for withdrawal of enteral feeding in children with chronic kidney disease stage 5D or 5T.

Background: Children with chronic kidney disease (CKD) stage 5 may require long-term enteral tube feeding. However, the factors associated with the need for tube feeding and the potential for its withdrawal are unclear.

Methods: This single-center, retrospective cohort study included patients with CKD stage 5D or 5T aged <18 years between 2004 and 2021.

Case of maternal uniparental isodisomy with autosomal recessive Alport syndrome combined with congenital myasthenia and Oguchi disease.

Uniparental isodisomy (UPiD) is a genetic condition in which an individual inherits two identical copies of a chromosome, or part of a chromosome, from one parent. UPiD can result in the development of autosomal recessive disorders if the chromosome inherited from one parent has a pathogenic variant. Herein, we present a 20 year-old female patient who had no significant family history including kidney, muscular, or ocular diseases.

Recovery from rituximab-associated persistent hypogammaglobulinaemia in children with nephrotic syndrome.

Background: There are limited data on the long-term outcomes and risk factors for non-recovery after development of rituximab (RTX)-associated persistent hypogammaglobulinaemia among children with idiopathic nephrotic syndrome (NS).

Methods: A nationwide Japanese survey was conducted to determine the prognosis of patients with childhood-onset idiopathic NS who developed persistent hypogammaglobulinaemia after RTX administration. Specifically, predictors of IgG level recovery and risk factors for serious infection were examined.

Efficacy of rituximab and risk factors for poor prognosis in patients with childhood-onset steroid-resistant nephrotic syndrome: a multicenter study.

Background: The efficacy of rituximab in steroid-resistant nephrotic syndrome (SRNS) is controversial. We previously reported that rituximab in combination with methylprednisolone pulse therapy (MPT) and immunosuppressants was associated with favorable outcomes. We determined risk factors for poor response following rituximab treatment, which remains unknown.

Frequency and prognosis of peritoneal dialysis-associated peritonitis in children.

Background: Peritonitis is the leading cause of peritoneal dialysis (PD) discontinuation. However, few data concern risk factors of peritonitis development and catheter removal caused by treatment failure in pediatric patients.

Methods: This single-center, retrospective study analyzed data from pediatric patients who underwent chronic PD between March 2002 and June 2022.

Living-donor liver transplantation for methylmalonic acidemia patient with hepatocellular carcinoma: A case report and literature review.

Background: Methylmalonic acidemia (MMA) is an autosomal recessive disorder caused by defects in propionyl-CoA (P-CoA) catabolism; of note, liver neoplasms rarely occur as a long-term complication of the disorder. Herein, we report the case of a patient with MMA and hepatocellular carcinoma (HCC) who was successfully treated with a living-donor liver transplant (LDLT) following prior kidney transplantation.

Case Report: A 25-year-old male patient with MMA underwent LDLT with a left lobe graft because of metabolic instability and liver neoplasms.

Feasibility of discontinuing immunosuppression in children with idiopathic nephrotic syndrome.

Background: Despite adverse events associated with the long-term use of immunosuppressants, their long-term discontinuation remains challenging in children with idiopathic nephrotic syndrome. Relapse and resumption of immunosuppressants after discontinuation and associated risk factors were analyzed.

Methods: This single-center retrospective cohort study included children with frequently relapsing/steroid-dependent nephrotic syndrome (FRNS/SDNS) or steroid-resistant nephrotic syndrome (SRNS) who initiated immunosuppressant treatment between 2010 and 2020.

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.

Rituximab in combination with cyclosporine and steroid pulse therapy for childhood-onset multidrug-resistant nephrotic syndrome: a multicenter single-arm clinical trial (JSKDC11 trial).

Background: Only 80% of children with idiopathic nephrotic syndrome respond well to glucocorticoid therapy. Multidrug-resistant nephrotic syndrome (MRNS) is associated with a poor kidney prognosis. Several retrospective studies have identified rituximab as an effective treatment for MRNS; however, prospective studies are required to assess its efficacy and safety.

Complications and prognosis of patients diagnosed with autosomal recessive polycystic kidney disease in neonatal period.

There are no clinical guidelines for performing nephrectomy in patients with autosomal recessive polycystic kidney disease (ARPKD). Few reports have described the clinical course of ARPKD diagnosed in the neonatal period in detail. Here, we report seven patients diagnosed with ARPKD and treated at our center during the neonatal period.

Risk factors for early dialysate leakage around the exit site after catheter placement in pediatric peritoneal dialysis: a single-center experience.

Background: Dialysate leakage, a major complication in peritoneal dialysis (PD), causes difficulty in continuing PD. However, literature evaluating risk factors for leakage in detail and the appropriate break-in period to avoid leakage in pediatric patients is scarce.

Methods: We conducted a retrospective study on children aged < 20 years who underwent Tenckhoff catheter placement between April 1, 2002, and December 31, 2021, at our institution.

Postoperative management and complications after abdominal surgery in children receiving peritoneal dialysis.

Background: Patients on peritoneal dialysis (PD) may develop PD-related complications that necessitate abdominal surgery. However, when to resume PD and how to prescribe PD fluid after surgery in pediatric patients are unknown.

Methods: Patients on PD who underwent small-incision abdominal surgery between May 2006 and October 2021 were included in this retrospective observational study.

CD4 + and CD8 + T-lymphocyte number as predictive marker of relapse after rituximab treatment in childhood-onset refractory nephrotic syndrome.

Background: Rituximab is a promising option for refractory idiopathic nephrotic syndrome. However, no simple predictive markers for relapse after rituximab have been established. To determine such markers, we investigated the relationship between CD4 + and CD8 + cell counts and relapse after rituximab administration.

Live attenuated vaccines in patients receiving immunosuppressive agents.

The use of live attenuated vaccines in patients with immunosuppressive agents is contraindicated in package inserts and guidelines in Japan and other countries. However, patients receiving immunosuppressants have a high risk of infectious disease becoming severe, and the necessity to prevent infectious disease is high. To date, 2,091 vaccinations have been reported in 25 reports of live attenuated vaccines in people receiving immunosuppressants.

A multicenter retrospective study of calcineurin inhibitors in nephrotic syndrome secondary to podocyte gene variants.

While 44-83% of children with steroid-resistant nephrotic syndrome (SRNS) without a proven genetic cause respond to treatment with a calcineurin inhibitor (CNI), current guidelines recommend against the use of immunosuppression in monogenic SRNS. This is despite existing evidence suggesting that remission with CNI treatment is possible and can improve prognosis in some cases of monogenic SRNS. Herein, our retrospective study assessed response frequency, predictors of response and kidney function outcomes among children with monogenic SRNS treated with a CNI for at least three months.