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 IgA nephropathy and IgA vasculitis nephritis.

IgA nephropathy and IgA vasculitis with nephritis, albeit rare, represent two relatively frequent glomerular conditions in childhood. Compared to adults, pediatric IgA nephropathy has a more acute presentation, most frequently with synpharyngitic macrohematuria and histologically with more intense inflammation and less intense chronic damage. Management of these conditions is controversial and supported by little high-quality evidence. The paucity of evidence is due to the disease heterogeneity, its inter-ethnic variability, and the difficulty of extrapolating data from adult studies due to the peculiarities of the condition in children. IgA vasculitis with nephritis is a kidney manifestation of a systemic disorder, typical of the pediatric age, in which both the diagnosis of kidney involvement and its management are poorly defined, and an interdisciplinary approach is crucial. Both conditions can have a profound and long-lasting impact on kidney function and the global health of affected children. The International Pediatric Nephrology Association has therefore convened a diverse international group of experts from different disciplines to provide guidance on the recommended management of these conditions in children and to establish common definitions and define priorities for future high-quality, evidence-based collaborative studies for the benefit of children.

Longitudinal analysis of blood pressure and lipids in childhood nephrotic syndrome.

BACKGROUND: In the current study, longitudinal BP and lipid measurements were examined in a NEPTUNE cohort of children with newly diagnosed nephrotic syndrome (cNEPTUNE). We hypothesized that hypertensive BP and dyslipidemia would persist in children with nephrotic syndrome, regardless of steroid treatment response. METHODS: A multi-center longitudinal observational analysis of data obtained from children < 19 years of age with new onset nephrotic syndrome enrolled in the Nephrotic Syndrome Study Network (cNEPTUNE) was conducted. BP and lipid data were examined over time stratified by disease activity and steroid exposure. Generalized estimating equation regressions were used to find determinants of hypertensive BP and dyslipidemia. RESULTS: Among 122 children, the prevalence of hypertensive BP at any visit ranged from 17.4% to 57.4%, while dyslipidemia prevalence ranged from 40.0% to 96.2% over a median of 30 months of follow-up. Hypertensive BP was found in 46.2% (116/251) of study visits during active disease compared with 31.0% (84/271) of visits while in remission. Dyslipidemia was present in 88.2% (120/136) of study visits during active disease and in 66.0% (101/153) while in remission. Neither dyslipidemia nor hypertensive BP were significantly different with/without medication exposure (steroids and/or CNI). In regression analysis, male sex and urine protein:creatinine ratio (UPC) were significant determinants of hypertensive BP over time, while eGFR was found to be a determinant of dyslipidemia over time. CONCLUSIONS: Results demonstrate persistent hypertensive BPs and unfavorable lipid profiles in the cNEPTUNE cohort regardless of remission status or concurrent steroid or calcineurin inhibitor treatment.

Precision nephrology identified tumor necrosis factor activation variability in minimal change disease and focal segmental glomerulosclerosis.

The diagnosis of nephrotic syndrome relies on clinical presentation and descriptive patterns of injury on kidney biopsies, but not specific to underlying pathobiology. Consequently, there are variable rates of progression and response to therapy within diagnoses. Here, an unbiased transcriptomic-driven approach was used to identify molecular pathways which are shared by subgroups of patients with either minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS). Kidney tissue transcriptomic profile-based clustering identified three patient subgroups with shared molecular signatures across independent, North American, European, and African cohorts. One subgroup had significantly greater disease progression (Hazard Ratio 5.2) which persisted after adjusting for diagnosis and clinical measures (Hazard Ratio 3.8). Inclusion in this subgroup was retained even when clustering was limited to those with less than 25% interstitial fibrosis. The molecular profile of this subgroup was largely consistent with tumor necrosis factor (TNF) pathway activation. Two TNF pathway urine markers were identified, tissue inhibitor of metalloproteinases-1 (TIMP-1) and monocyte chemoattractant protein-1 (MCP-1), that could be used to predict an individual's TNF pathway activation score. Kidney organoids and single-nucleus RNA-sequencing of participant kidney biopsies, validated TNF-dependent increases in pathway activation score, transcript and protein levels of TIMP-1 and MCP-1, in resident kidney cells. Thus, molecular profiling identified a subgroup of patients with either MCD or FSGS who shared kidney TNF pathway activation and poor outcomes. A clinical trial testing targeted therapies in patients selected using urinary markers of TNF pathway activation is ongoing.

Racial and Ethnic Disparities in Acute Care Utilization Among Patients With Glomerular Disease.

RATIONALE & OBJECTIVE: The effects of race, ethnicity, socioeconomic status (SES), and disease severity on acute care utilization in patients with glomerular disease are unknown. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 1,456 adults and 768 children with biopsy-proven glomerular disease enrolled in the Cure Glomerulonephropathy (CureGN) cohort. EXPOSURE: Race and ethnicity as a participant-reported social factor. OUTCOME: Acute care utilization defined as hospitalizations or emergency department visits. ANALYTICAL APPROACH: Multivariable recurrent event proportional rate models were used to estimate associations between race and ethnicity and acute care utilization. RESULTS: Black or Hispanic participants had lower SES and more severe glomerular disease than White or Asian participants. Acute care utilization rates were 45.6, 29.5, 25.8, and 19.2 per 100 person-years in Black, Hispanic, White, and Asian adults, respectively, and 55.8, 42.5, 40.8, and 13.0, respectively, for children. Compared with the White race (reference group), Black race was significantly associated with acute care utilization in adults (rate ratio [RR], 1.76 [95% CI, 1.37-2.27]), although this finding was attenuated after multivariable adjustment (RR, 1.31 [95% CI, 1.03-1.68]). Black race was not significantly associated with acute care utilization in children; Asian race was significantly associated with lower acute care utilization in children (RR, 0.32 [95% CI 0.14-0.70]); no significant associations between Hispanic ethnicity and acute care utilization were identified. LIMITATIONS: We used proxies for SES and lacked direct information on income, household unemployment, or disability. CONCLUSIONS: Significant differences in acute care utilization rates were observed across racial and ethnic groups in persons with prevalent glomerular disease, although many of these difference were explained by differences in SES and disease severity. Measures to combat socioeconomic disadvantage in Black patients and to more effectively prevent and treat glomerular disease are needed to reduce disparities in acute care utilization, improve patient wellbeing, and reduce health care costs.

COL4A gene variants are common in children with hematuria and a family history of kidney disease.

BACKGROUND: Inherited kidney diseases are a common cause of chronic kidney disease (CKD) in children. Identification of a monogenic cause of CKD is more common in children than in adults. This study evaluated the diagnostic yield and phenotypic spectrum of children who received genetic testing through the KIDNEYCODE sponsored genetic testing program. METHODS: Unrelated children < 18 years of age who received panel testing through the KIDNEYCODE sponsored genetic testing program from September 2019 through August 2021 were included (N = 832). Eligible children met at least one of the following clinician-reported criteria: estimated GFR ≤ 90 ml/min/1.73 m2, hematuria, a family history of kidney disease, or suspected or biopsy confirmed Alport syndrome or focal segmental glomerulosclerosis (FSGS) in the tested individual or family member. RESULTS: A positive genetic diagnosis was observed in 234 children (28.1%, 95% CI [25.2-31.4%]) in genes associated with Alport syndrome (N = 213), FSGS (N = 9), or other disorders (N = 12). Among children with a family history of kidney disease, 30.8% had a positive genetic diagnosis. Among those with hematuria and a family history of CKD, the genetic diagnostic rate increased to 40.4%. CONCLUSIONS: Children with hematuria and a family history of CKD have a high likelihood of being diagnosed with a monogenic cause of kidney disease, identified through KIDNEYCODE panel testing, particularly COL4A variants. Early genetic diagnosis can be valuable in targeting appropriate therapy and identification of other at-risk family members. A higher resolution version of the Graphical abstract is available as Supplementary information.

The association of low birthweight and prematurity on outcomes in children and adults with nephrotic syndrome-a NEPTUNE cohort study.

BACKGROUND: In single-center studies, both preterm birth and low birth weight (LBW) are associated with worse outcomes in childhood nephrotic syndrome. Using the Nephrotic Syndrome Study Network (NEPTUNE) observational cohort, we tested the hypothesis that in patients with nephrotic syndrome, hypertension, proteinuria status, and disease progression would be more prevalent and more severe in subjects with LBW and prematurity singly or in combination (LBW/prematurity). METHODS: Three hundred fifty-nine adults and children with focal segmental glomerulosclerosis (FSGS) or minimal change disease (MCD) and available birth history were included. Estimated glomerular filtration rate (eGFR) decline and remission status were primary outcomes, and secondary outcomes were kidney histopathology, kidney gene expression, and urinary biomarkers. Logistic regression was used to identify associations with LBW/prematurity and these outcomes. RESULTS: We did not find an association between LBW/prematurity and remission of proteinuria. However, LBW/prematurity was associated with greater decline in eGFR. This decline in eGFR was partially explained by the association of LBW/prematurity with APOL1 high-risk alleles, but the association remained after adjustment. There were no differences in kidney histopathology or gene expression in the LBW/prematurity group compared to normal birth weight/term birth. CONCLUSION: LBW and premature babies who develop nephrotic syndrome have a more rapid decline in kidney function. We did not identify clinical or laboratory features that distinguished the groups. Additional studies in larger groups are needed to fully ascertain the effects of (LBW) and prematurity alone or in combination on kidney function in the setting of nephrotic syndrome.

Tobacco exposure in adults and children with proteinuric glomerulopathies: a NEPTUNE cohort study.

BACKGROUND: Tobacco exposure has been recognized as a risk factor for cardiovascular disease (CVD) and progression of kidney disease. Patients with proteinuric glomerulopathies are at increased risk for cardiovascular morbidity and mortality. Multiple studies have linked tobacco exposure to CVD and chronic kidney disease, but the relationships between smoking and proteinuric glomerulopathies in adults and children have not been previously explored. METHODS: Data from the Nephrotic Syndrome Study Network (NEPTUNE), a multi-center prospective observational study of participants with proteinuric glomerulopathies, was analyzed. 371 adults and 192 children enrolled in NEPTUNE were included in the analysis. Self-reported tobacco exposure was classified as non-smoker, active smoker, former smoker, or exclusive passive smoker. Baseline serum cotinine levels were measured in a sub-cohort of 178 participants. RESULTS: The prevalence of active smokers, former smokers and exclusive passive smoking among adults at baseline was 14.6%, 29.1% and 4.9%, respectively. Passive smoke exposure was 16.7% among children. Active smoking (reference non-smoking) was significantly associated with greater total cholesterol among adults (ß 17.91 95% CI 0.06, 35.76, p = 0.049) while passive smoking (reference non-smoking) was significantly associated with greater proteinuria over time among children (ß 1.23 95% CI 0.13, 2.33, p = 0.03). Higher cotinine levels were associated with higher baseline eGFR (r = 0.17, p = 0.03). CONCLUSION: Tobacco exposure is associated with greater risk for CVD and worse kidney disease outcomes in adults and children with proteinuric glomerulopathies. Preventive strategies to reduce tobacco exposure may help protect against future cardiovascular and kidney morbidity and mortality in patients with proteinuric glomerulopathies.

Seeking Racial Equity in Hematology and Oncology: a Fellow-Led Educational Series to Promote Reflection and Action.

The USA is experiencing a reckoning with racial injustice and graduate medical education programs are seeking ways to address this important topic in training. Fellows in hematology/oncology at the University of North Carolina recognized this important gap and adapted a curriculum for medical residents on racial equity to a subspecialty audience. Aims were (1) to improve knowledge and awareness about implicit bias and systemic racism and (2) introduce methods to address racial inequities. We used lived experiences and collated materials from scientific literature and lay media to illustrate key points. The course explored the effects of implicit bias on individual, clinical, and health system levels, anchored in Kahneman's two-system theory. Videos, journal articles, and group discussion were employed to appeal to many learning styles. A post-curriculum survey assessed perceptions of racial inequality in medicine and the series' effects using a Likert scale. Twenty-nine participants completed the survey (12 fellows), 71% reported improved awareness of racial inequities, and 61% reported improved comfort level in addressing racial inequities. All participants recognized at least "some" racial inequity in medicine, and over 75% of participants indicated interest in further sessions. Formulation of an educational curriculum by fellows and delivered in a division-wide setting was feasible and well received by participants, filling a key educational gap. We encourage other institutions to take similar steps to highlight issues of systemic racism and move our field in the right direction.

Efficacy and safety of voclosporin versus placebo for lupus nephritis (AURORA 1): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial.

BACKGROUND: Voclosporin, a novel calcineurin inhibitor approved for the treatment of adults with lupus nephritis, improved complete renal response rates in patients with lupus nephritis in a phase 2 trial. This study aimed to evaluate the efficacy and safety of voclosporin for the treatment of lupus nephritis. METHODS: This multicentre, double-blind, randomised phase 3 trial was done in 142 hospitals and clinics across 27 countries. Patients with a diagnosis of systemic lupus erythematosus with lupus nephritis according to the American College of Rheumatology criteria, and a kidney biopsy within 2 years that showed class III, IV, or V (alone or in combination with class III or IV) were eligible. Patients were randomly assigned (1:1) to oral voclosporin (23·7 mg twice daily) or placebo, on a background of mycophenolate mofetil (1 g twice daily) and rapidly tapered low-dose oral steroids, by use of an interactive web response system. The primary endpoint was complete renal response at 52 weeks defined as a composite of urine protein creatinine ratio of 0·5 mg/mg or less, stable renal function (defined as estimated glomerular filtration rate [eGFR] ≥60 mL/min/1·73 m2 or no confirmed decrease from baseline in eGFR of >20%), no administration of rescue medication, and no more than 10 mg prednisone equivalent per day for 3 or more consecutive days or for 7 or more days during weeks 44 through 52, just before the primary endpoint assessment. Safety was also assessed. Efficacy analysis was by intention-to-treat and safety analysis by randomised patients receiving at least one dose of study treatment. The trial is registered with ClinicalTrials.gov, NCT03021499. FINDINGS: Between April 13, 2017, and Oct 10, 2019, 179 patients were assigned to the voclosporin group and 178 to the placebo group. The primary endpoint of complete renal response at week 52 was achieved in significantly more patients in the voclosporin group than in the placebo group (73 [41%] of 179 patients vs 40 [23%] of 178 patients; odds ratio 2·65; 95% CI 1·64-4·27; p<0·0001). The adverse event profile was balanced between the two groups; serious adverse events occurred in 37 (21%) of 178 in the voclosporin group and 38 (21%) of 178 patients in the placebo group. The most frequent serious adverse event involving infection was pneumonia, occurring in 7 (4%) patients in the voclosporin group and in 8 (4%) patients in the placebo group. A total of six patients died during the study or study follow-up period (one [<1%] patient in the voclosporin group and five [3%] patients in the placebo group). None of the events leading to death were considered by the investigators to be related to the study treatments. INTERPRETATION: Voclosporin in combination with MMF and low-dose steroids led to a clinically and statistically superior complete renal response rate versus MMF and low-dose steroids alone, with a comparable safety profile. This finding is an important advancement in the treatment of patients with active lupus nephritis. FUNDING: Aurinia Pharmaceuticals.