Kidney outcomes for children with lupus nephritis

Renal vascular lesions in childhood-onset lupus nephritis

BACKGROUND

This study aimed to determine the clinical significance of renal vascular lesions (RVLs) in childhood-onset lupus nephritis (cLN).

METHODS

We retrospectively reviewed all children with biopsy-proven cLN between 2004-2020 to evaluate the prevalence of RVLs on kidney biopsy and its associated factors and long-term outcomes. The composite kidney outcome was defined as advanced chronic kidney disease (CKD) stage 3-5, kidney failure and death.

RESULTS

107 biopsies from 84 Chinese patients were analysed. RVLs were observed in 19 patients (22.6%), including non-inflammatory necrotizing vasculopathy (NNV, n = 6), thrombotic microangiopathy (TMA, n = 4), arterial sclerosis (AS, n = 3), concurrent NNV with AS (n = 4), concurrent NNV with TMA (n = 1) and concurrent true renal vasculitis with AS (n = 1). The presence of RVLs was associated with lower estimated glomerular filtration rate (eGFR) (66.9 ± 40.3 vs. 95.6 ± 39.4 ml/min/1.73m2, p = 0.005), haemoglobin level (9.1 ± 1.9 vs. 10.4 ± 1.9 g/dL, p = 0.008) and platelet count (150.1 ± 96.4 vs. 217.2 ± 104.8 × 109/L, p = 0.01). LN classes and activity/chronicity indices were similar. Patients with RVLs had poorer composite kidney outcomes, though not reaching statistical significance (log-rank test, p = 0.06). The presence of NNV was associated with inferior survival free from composite kidney outcome (log-rank test, p = 0.0018), compared to other forms of RVLs and those without RVLs. Univariate analysis revealed NNV (HR 7.08, 95% CI 1.67-30.03) was predictive of composite kidney outcome.

CONCLUSION

RVLs are present in one-fifth of cLN patients and are associated with severe presentation. NNV is associated with worse long-term kidney outcome. Routine evaluation of RVLs is warranted and should be incorporated into future classification criteria.

Efficacy and safety of belimumab combined with the standard regimen in treating children with lupus nephritis

The purpose of this study is to evaluate the efficacy and safety of belimumab combined with the standard regimen in treating children with active lupus nephritis. This single-center, retrospective cohort study used clinical data of children with newly active lupus nephritis hospitalized in the Department of Nephrology between December 2004 and February 2023. Patients were divided into a belimumab or traditional treatment group according to whether or not they received belimumab. Renal remission and recurrence rates and glucocorticoid dose were compared between groups. Forty-seven children (median age 11 years) were enrolled, including 30 and 17 children in the traditional treatment and belimumab groups, respectively. The Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2000) score of children in the belimumab group (23.59 ± 7.78) was higher than that in the traditional treatment group (19.13 ± 6.10) (P = 0.035). The two groups showed no significant difference in the frequency of pyuria, gross hematuria, and the levels of 24-h proteinuria and estimated glomerular filtration rate. The complement C3/C4 in the belimumab group recovered faster than that in the traditional treatment group (P < 0.05). There were no between-group differences in the complete renal remission rate at 6 or 12 months (P = 0.442, P = 0.759). There were no between-group differences in 1-year recurrence rate (P = 0.303). Furthermore, 6 and 12 months after treatment, glucocorticoid doses were lower in the belimumab than the traditional treatment group (17.87 ± 6.96 mg/d vs. 27.33 ± 8.40 mg/d, P = 0.000; 10.00 (5.3) mg/d vs. 13.75 (10.0) mg/d, P = 0.007), respectively.

CONCLUSION

With an equivalent renal remission rate, belimumab combined with the standard traditional regimen might promote the tapering of glucocorticoids, and the incidence of adverse events is low.

WHAT IS KNOWN

• Belimumab is documented as an adjunctive treatment with systemic lupus erythematosus (c-SLE) LN with efficacy. • Due to the paucity of studies, its effects and side effects in children with LN remain unclear.

WHAT IS NEW

• This single-center, retrospective cohort study evaluated the efficacy and safety of belimumab combined with the standard regimen in treating children with proliferative LN. • Belimumab combined with the standard traditional treatment might promote the tapering of glucocorticoids, while exhibiting a low occurrence of adverse events.

Extrapolation of the Efficacy and Pharmacokinetics of Belimumab to Support its Use in Children with Lupus Nephritis

BACKGROUND AND OBJECTIVE

Lupus nephritis (LN), a severe manifestation of systemic lupus erythematosus, has greater severity in children versus adults. Belimumab is approved for systemic lupus erythematosus treatment in patients aged ≥ 5 years, and for active LN in adults in the European Union, China, Japan and Latin America, and patients aged ≥ 5 years in the USA. Low prevalence of paediatric active LN makes conducting a clinical study within a reasonable period unfeasible. We describe a model-based extrapolation of belimumab efficacy and pharmacokinetics from adults to children with LN to support US Food and Drug Administration approval of intravenous belimumab 10 mg/kg (administered every 4 weeks after the loading dose) in children (aged 5-17 years) with active LN.

METHODS

This concept assumed that disease progression, response to belimumab, exposure-response, and the target belimumab exposure for efficacy are similar across adult and paediatric systemic lupus erythematosus and LN, evaluated against the published literature for paediatric LN and belimumab systemic lupus erythematosus and LN clinical trial data in adults and children. A two-compartmental population pharmacokinetic model, previously developed for adults with LN, was used to extrapolate belimumab pharmacokinetics to children with LN.

RESULTS

The model captured the dependence of time-varying proteinuria on belimumab clearance, and therefore exposure. Sufficient target exposures for efficacy were achieved in children with active LN. A small proportion of children aged 5-11 years are predicted to have exposures below adult levels but no impact to efficacy is expected.

CONCLUSIONS

Our model demonstrated that intravenous belimumab 10 mg/kg every 4 weeks is appropriate for children aged 5-17 years with active LN.

[Correlation of anti-C1q antibodies with active systemic lupus erythematosus and lupus nephritis in children]

OBJECTIVES

To study the correlation of anti-C1q antibodies with active systemic lupus erythematosus (SLE) and lupus nephritis (LN) in children, as well as their diagnostic value for active SLE and LN.

METHODS

A retrospective selection of 90 hospitalized children with SLE at the Children's Medical Center of Second Xiangya Hospital, Central South University from January 2016 to March 2019 as the SLE group, all of whom were tested for anti-C1q antibodies. A control group was formed by collecting 70 hospitalized children with other autoimmune diseases (OAD) during the same period. The differences in anti-C1q antibody levels were compared between two groups.The correlation of anti-C1q antibodies with various indicators of SLE and LN was analyzed, and the diagnostic value of anti-C1q in SLE and LN was evaluated.

RESULTS

The serum levels of anti-C1q antibodies in the SLE group were higher than those in the OAD group (P<0.05). The SLE disease activity index score was positively correlated with anti-C1q antibodies (rs=0.371, P<0.001) and positively correlated with anti-double-stranded DNA antibodies (rs=0.370, P<0.001). The sensitivity and specificity of anti-C1q antibodies for diagnosing active SLE were 89.90% and 53.90%, respectively, with an area under the curve of 0.720 (P<0.05) and a critical value of 5.45 U/mL. The sensitivity and specificity of anti-C1q antibody levels for diagnosing active LN were 58.50% and 85.00%, respectively, with an area under the curve of 0.675 (P<0.05) and a critical value of 22.05 U/mL.

CONCLUSIONS

Anti-C1q antibodies can serve as non-invasive biomarkers for evaluating the activity of SLE or predicting the activity of LN in children.

Predicting wait time for pediatric kidney transplant: a novel index

BACKGROUND

Over one thousand pediatric kidney transplant candidates are added to the waitlist annually, yet the prospective time spent waiting is unknown for many. Our study fills this gap by identifying variables that impact waitlist time and by creating an index to predict the likelihood of a pediatric candidate receiving a transplant within 1 year of listing. This index could be used to guide patient management by giving clinicians a potential timeline for each candidate's listing based on a unique combination of risk factors.

METHODS

A retrospective analysis of 3757 pediatric kidney transplant candidates from the 2014 to 2020 OPTN/UNOS database was performed. The data was randomly divided into a training set, comprising two-thirds of the data, and a testing set, comprising one-third of the data. From the training set, univariable and multivariable logistic regressions were used to identify significant predictive factors affecting wait times. A predictive index was created using variables significant in the multivariable analysis. The index's ability to predict likelihood of transplantation within 1 year of listing was validated using ROC analysis on the training set. Validation of the index using ROC analysis was repeated on the testing set.

RESULTS

A total of 10 variables were found to be significant. The five most significant variables include the following: blood group, B (OR 0.65); dialysis status (OR 3.67); kidney disease etiology, SLE (OR 0.38); and OPTN region, 5 (OR 0.54) and 6 (OR 0.46). ROC analysis of the index on the training set yielded a c-statistic of 0.71. ROC analysis of the index on the testing set yielded a c-statistic of 0.68.

CONCLUSIONS

This index is a modest prognostic model to assess time to pediatric kidney transplantation. It is intended as a supplementary tool to guide patient management by providing clinicians with an individualized prospective timeline for each candidate. Early identification of candidates with potential for prolonged waiting times may help encourage more living donation including paired donation chains.

Early-onset lupus nephritis

Early-onset systemic lupus erythematous (SLE) is a distinct clinical entity characterized by the onset of disease manifestations during childhood. Despite some similarities to patients who are diagnosed during adulthood, early-onset SLE typically displays a greater disease severity, with aggressive multiorgan involvement, lower responsiveness to classical therapies, and more frequent flares. Lupus nephritis is one of the most severe complications of SLE and represents a major risk factor for long-term morbidity and mortality, especially in children. This review focuses on the clinical and histological aspects of early-onset lupus nephritis, aiming at highlighting relevant differences with adult patients, emphasizing long-term outcomes and discussing the management of long-term complications. We also discuss monogenic lupus, a spectrum of conditions caused by single gene variants affecting the complement cascade, extracellular and intracellular nucleic acid sensing and processing, and occasionally other metabolic pathways. These monogenic forms typically develop early in life and often have clinical manifestations that resemble sporadic SLE, whereas their response to standard treatments is poor.

Prognostic Value of the 2019 EULAR/American College of Rheumatology Systemic Lupus Erythematosus Classification Criteria to Renal Response One Year After Treatment in a Cohort With Childhood-Onset Lupus Nephritis

OBJECTIVE

In 2019, the EULAR/American College of Rheumatology developed classification criteria for systemic lupus erythematosus (SLE). A positive correlation between summary score at diagnosis and SLE disease activity at five years has been noted in adult patients with lupus, but little is known among the pediatric population. We evaluated the prognostic value of higher summary scores and number of extrarenal domains at diagnosis (low/moderate number [1-5] vs high number [6-9]) to renal outcomes after one year of treatment in pediatric patients with lupus nephritis (LN).

METHODS

This retrospective, single-center cohort study included 74 pediatric patients with LN. Published pediatric renal response definitions were used for our outcome measure (no, partial, and complete response). Descriptive statistics were reported, and an ordinal logistic regression estimated adjusted odds ratios (ORs) for renal response including 95% confidence intervals (CIs).

RESULTS

Patients with high extrarenal domains had OR 1.47 (95% CI 0.55-2.91) of having a complete renal response compared to patients with low/moderate domains. Patients with a summary score <30 had OR 1.31 (95% CI 0.50-3.44) of having a complete renal response relative to a summary score ≥30, though a larger proportion of patients with a summary score of ≥30 had no renal response after one year of treatment.

CONCLUSION

More extrarenal domains at diagnosis did not have a statistically significant impact on renal response at one year, nor did a higher summary score. However, a larger portion of patients with a summary score <30 achieved complete renal response compared to patients with a score ≥30.

IFN-I Score and Rare Genetic Variants in Children with Systemic Lupus Erythematosus

Introduction: Interferon I (IFN I) signaling hyperactivation is considered one of the most important pathogenetic mechanisms in systemic lupus erythematosus (SLE). Early manifestation and more severe SLE courses in children suggest a stronger genetic influence in childhood-onset SLE (cSLE). Aim: To evaluate IFN-I score and SLE-associated genetic variants in cSLE. Material and Methods: 80 patients with cSLE were included in the study. IFN I-score was assessed by real-time PCR quantitation of 5 IFN I-regulated transcripts (IFI44L, IFI44, IFIT3, LY6E, MXA1) in 60 patients. Clinical exome sequencing (CES) was performed in 51 patients. Whole-exome sequencing was performed in 32 patients with negative results of CES. Results: 46/60 patients (77%) had elevated IFN-I scores. Leucopenia and skin involvement were associated with over-expression of IFI44 and IFI44L, while hypocomplementemia-with hyperactivation of IFIT3, LY6E, and MX1. No correlation of IFN-I score with disease activity was found. At least one rare genetic variant, potentially associated with SLE, was found in 29 (56.9%) patients. The frequency of any SLE-genetic variants in patients with increased IFN scores was 84%, in patients with normal IFN scores-33%, and in the group whose IFN score was not assessed was 65% (p = 0.040). The majority of genetic variants (74%) are functionally related to nucleic acid sensing and IFN-signaling. The highest frequency of genetic variants was observed in Sakha patients (9/14; 64.3%); three and two unrelated patients had identical variants in PTPN22 and TREX1 genes, respectively. Conclusions: More than half of patients with childhood-onset SLE have rare variants in SLE-associated genes. The IFN-I score could be considered a tool for the selection of patients for further genetic assessment in whom monogenic lupus is suspected.

Efficacy and Safety of Pharmacokinetically-Driven Dosing of Mycophenolate Mofetil for the Treatment of Pediatric Proliferative Lupus Nephritis-A Double-Blind Placebo Controlled Clinical Trial (The Pediatric Lupus Nephritis Mycophenolate Mofetil Study)

Background

The safety and efficacy of mycophenolate mofetil (MMF) for lupus nephritis (LN) treatment is established in adults and in some children. MMF is rapidly converted to the biologically active metabolite mycophenolic acid (MPA) whose pharmacokinetics (PK) is characterized by large inter- and intra-individual variability.

Methods/Design

This randomized, double-blind, active comparator, controlled clinical trial of pediatric subjects with proliferative LN compares pharmacokinetically-guided precision-dosing of MMF (MMFPK, i.e. the dose is adjusted to the target area under the concentration-time curve (AUC0-12h) of MPA ≥ 60-70 mg*h/L) and MMF dosed per body surface area (MMFBSA, i.e. MMF dosed 600 mg/m2 body surface area), with MMF dosage taken about 12 hours apart. At baseline, subjects are randomized 1:1 to receive blinded treatment with MMFPK or MMFBSA for up to 53 weeks. The primary outcome is partial clinical remission of LN (partial renal response, PRR) at week 26, and the major secondary outcome is complete renal response (CRR) at week 26. Subjects in the MMFBSA arm with PRR at week 26 will receive MMFPK from week 26 onwards, while subjects with CRR will continue MMFBSA or MMFPK treatment until week 53. Subjects who achieve PRR at week 26 are discontinued from study intervention.

Discussion

The Pediatric Lupus Nephritis Mycophenolate Mofetil (PLUMM) study will provide a thorough evaluation of the PK of MMF in pediatric LN patients, yielding a head-to-head comparison of MMFBSA and MMFPK for both safety and efficacy. This study has the potential to change current treatment recommendations for pediatric LN, thereby significantly impacting childhood-onset SLE (cSLE) disease prognosis and current clinical practice.

Antinuclear antibody-associated autoimmune cytopenia in childhood is a risk factor for systemic lupus erythematosus

ABSTRACT

Autoimmune cytopenia (AIC) in children may be associated with positive antinuclear antibodies (ANA) and may progress to systemic lupus erythematosus (SLE). We evaluated the risk of progression to SLE of childhood-onset ANA-associated AIC. In the French national prospective OBS'CEREVANCE cohort, the long-term outcome of children with ANA-associated AIC (ANA titer ≥1/160) and a subgroup of children who developed SLE were described. ANA were positive in 355 of 1803 (20%) children with AIC. With a median follow-up of 5.8 (range, 0.1-29.6) years, 79 of 355 (22%) patients developed SLE at a median age of 14.5 (1.1-21.4) years; 20% of chronic immune thrombocytopenic purpura, 19% of autoimmune hemolytic anemia, and 45% of Evans syndrome. None of the patients with ANA-negative test developed SLE. Severe manifestations of SLE were observed in 21 patients, and 2 patients died. In multivariate analysis including patients with positive ANA within the first 3 months after AIC diagnosis, age >10 years at AIC diagnosis (relative risk [RR], 3.67; 95% confidence interval [CI], 1.18-11.4; P = .024) and ANA titer >1/160 (RR, 5.28; 95% CI, 1.20-23.17; P = .027) were associated with the occurrence of SLE after AIC diagnosis. ANA-associated AIC is a risk factor for progression to SLE, especially in children with an initial ANA titer >1/160 and an age >10 years at AIC diagnosis. ANA screening should be recommended in children with AIC, and patients with ANA should be monitored long-term for SLE, with special attention to the transition period. This trial was registered at www.ClinicalTrials.gov as #NCT05937828.

Renal relapse in children and adolescents with childhood-onset lupus nephritis: a 20-year study

OBJECTIVES

There is little data on renal relapse in childhood-onset LN (cLN). We investigate the incidence, predictive factors and outcomes related to renal relapse.

METHODS

We conducted a retrospective cohort study of all cLN diagnosed at ≤18 years between 2001-2021 to investigate the incidence and outcomes related to renal relapse.

RESULTS

Ninety-five Chinese cLN patients (91% proliferative LN) were included. Induction immunosuppression was prednisolone and CYC [n = 36 (38%)] or MMF [n = 33 (35%)]. Maintenance immunosuppression was prednisolone and MMF [n = 53 (54%)] or AZA [n = 29 (31%)]. The rates of complete remission/partial remission (CR/PR) at 12 months were 78.9%/7.4%. Seventy renal relapses occurred in 39 patients over a follow-up of 10.2 years (s.d. 5.9) (0.07 episode/patient-year). Relapse-free survival was 94.7, 86.0, 80.1, 71.2, 68.3, 50.3 and 44.5% at 1, 2, 3, 4, 5, 10 and 20 years, respectively. Multivariate analysis showed that LN diagnosis <13.1 years [adjusted hazard ratio (HRadj) 2.59 995% CI 1.27, 5.29), P = 0.01], AZA maintenance [HRadj 2.20 (95% CI 1.01, 4.79), P = 0.05], PR [HRadj 3.9 (95% CI 1.03, 9.19), P = 0.01] and non-remission [HRadj 3.08 (95% CI 1.35, 11.3), P = 0.04] at 12 months were predictive of renal relapse. Renal relapse was significantly associated with advanced chronic kidney disease (stages 3-5) and end-stage kidney disease (17.9% vs 1.8%, P < 0.01). Furthermore, patients with renal relapse showed an increased incidence of infections (30.8% vs 10.7%, P = 0.02), osteopenia (38.5% vs 17.9%, P = 0.04) and hypertension (30.8% vs 7.1%, P < 0.01).

CONCLUSION

Renal relapse is common among cLN, especially among young patients, and is associated with an increased incidence of morbidity and mortality. Attaining CR and the use of MMF appear to decrease the incidence of renal relapse.

Managing Lupus Nephritis in Children and Adolescents

Lupus nephritis is an important manifestation of systemic lupus erythematosus, which leads to chronic kidney disease, kidney failure, and can result in mortality. About 35%-60% of children with systemic lupus erythematosus develop kidney involvement. Over the past few decades, the outcome of patients with lupus nephritis has improved significantly with advances in immunosuppressive therapies and clinical management. Nonetheless, there is a paucity of high-level evidence to guide the management of childhood-onset lupus nephritis, because of the relatively small number of patients at each centre and also because children and adolescents are often excluded from clinical trials. Children and adults differ in more ways than just size, and there are remarkable differences between childhood- and adult-onset lupus nephritis in terms of disease severity, treatment efficacy, tolerance to medications and most importantly, psychosocial perspective. In this article, we review the 'art and science' of managing childhood-onset lupus nephritis, which has evolved in recent years, and highlight special considerations in this specific patient population.

Renal Response Outcomes of the EuroLupus and National Institutes of Health Cyclophosphamide Dosing Regimens in Childhood-Onset Proliferative Lupus Nephritis

OBJECTIVE

We compared clinical characteristics and renal response in patients with childhood-onset proliferative lupus nephritis (LN) treated with the EuroLupus versus National Institutes of Health (NIH) cyclophosphamide (CYC) regimen.

METHODS

A retrospective cohort study was conducted at 11 pediatric centers in North America that reported using both CYC regimens. Data were extracted from the electronic medical record at baseline and 3, 6, and 12 months after treatment initiation with CYC. To evaluate the adjusted association between CYC regimen (EuroLupus vs NIH) and renal response over time, generalized estimating equations with a logit link were used. An interaction between time and CYC regimen was included, and a contrast between CYC regimens at 12 months was used to evaluate the primary outcome.

RESULTS

One hundred forty-five patients (58 EuroLupus, 87 NIH) were included. EuroLupus patients were on average older at the start of current CYC therapy, had longer disease duration, and more commonly had relapsed or refractory LN compared with the NIH group. After multivariable adjustment, there was no significant association between CYC regimen and achieving complete renal response at 12 months (odds ratio [OR] of response for the EuroLupus regimen, reference NIH regimen: 0.76; 95% confidence interval [CI] 0.29-1.98). There was also no significant association between CYC regimen and achieving at least a partial renal response at 12 months (OR 1.35, 95% CI 0.57-3.19).

CONCLUSION

Our study failed to demonstrate a benefit of the NIH regimen over the EuroLupus CYC regimen in childhood-onset proliferative LN. However, future prospective outcome studies are needed.

Comorbidity patterns in cardiovascular diseases: the role of life-stage and socioeconomic status

Cardiovascular diseases stand as a prominent global cause of mortality, their intricate origins often entwined with comorbidities and multimorbid conditions. Acknowledging the pivotal roles of age, sex, and social determinants of health in shaping the onset and progression of these diseases, our study delves into the nuanced interplay between life-stage, socioeconomic status, and comorbidity patterns within cardiovascular diseases. Leveraging data from a cross-sectional survey encompassing Mexican adults, we unearth a robust association between these variables and the prevalence of comorbidities linked to cardiovascular conditions. To foster a comprehensive understanding of multimorbidity patterns across diverse life-stages, we scrutinize an extensive dataset comprising 47,377 cases diagnosed with cardiovascular ailments at Mexico's national reference hospital. Extracting sociodemographic details, primary diagnoses prompting hospitalization, and additional conditions identified through ICD-10 codes, we unveil subtle yet significant associations and discuss pertinent specific cases. Our results underscore a noteworthy trend: younger patients of lower socioeconomic status exhibit a heightened likelihood of cardiovascular comorbidities compared to their older counterparts with a higher socioeconomic status. By empowering clinicians to discern non-evident comorbidities, our study aims to refine therapeutic designs. These findings offer profound insights into the intricate interplay among life-stage, socioeconomic status, and comorbidity patterns within cardiovascular diseases. Armed with data-supported approaches that account for these factors, clinical practices stand to be enhanced, and public health policies informed, ultimately advancing the prevention and management of cardiovascular disease in Mexico.

Long-term outcomes with rituximab as add-on therapy in severe childhood-onset lupus nephritis

BACKGROUND

Long-term data pertaining to rituximab as add-on therapy in childhood-onset lupus nephritis (cLN) is scarce.

METHODS

A retrospective cohort study was conducted on all patients with proliferative cLN, diagnosed ≤ 18 years and between 2005 and 2021, who received rituximab for LN episodes that were life/organ threatening and/or treatment resistant to standard immunosuppression.

RESULTS

Fourteen patients with cLN (female, n = 10) were included, with median follow-up period of 6.9 years. LN episodes (class III, n = 1; class IV, n = 11; class IV + V, n = 2) requiring rituximab occurred at 15.6 years (IQR 12.8-17.3), urine protein:creatinine ratio was 8.2 mg/mg (IQR 3.4-10.1) and eGFR was 28 mL/min/1.73 m2 (IQR 24-69) prior to rituximab treatment. Ten and four patients received rituximab at 1500 mg/m2 and 750 mg/m2, which were given at 46.5 days (IQR 19-69) after commencement of standard therapies. Treatment with rituximab resulted in improvements in proteinuria (ps < 0.001), eGFR (ps < 0.01) and serological parameters, including haemoglobin levels, complement 3 levels and anti-dsDNA antibodies, compared with baseline. Rates of complete/partial remission at 6-, 12- and 24-month post-rituximab were 28.6/42.8%, 64.2/21.4% and 69.2/15.3%. All three patients who required acute kidney replacement therapy became dialysis-free after rituximab. Relapse rate following rituximab was 0.11 episodes/patient-year. There was no lethal complication or severe infusion reaction. Hypogammaglobulinaemia was the most frequent complication (45%) but was mostly asymptomatic. Neutropenia and infections were observed in 20% and 25% of treatments. Upon last follow-up, three (21%) and two (14%) patients developed chronic kidney disease (stage 2, n = 2; stage 4; n = 1) and kidney failure, respectively.

CONCLUSION

Add-on rituximab is an effective and safe rescue therapy for cLN patients with life-/organ-threatening manifestations or treatment-resistance. A higher resolution version of the Graphical abstract is available as Supplementary information.

International cohort of 382 children with lupus nephritis - presentation, treatment and outcome at 24 months

BACKGROUND

Children with lupus have a higher chance of nephritis and worse kidney outcome than adult patients.

METHODS

We retrospectively analyzed clinical presentation, treatment and 24-month kidney outcome in a cohort of 382 patients (≤ 18 years old) with lupus nephritis (LN) class ≥ III diagnosed and treated in the last 10 years in 23 international centers.

RESULTS

The mean age at onset was 11 years 9 months and 72.8% were females. Fifty-seven percent and 34% achieved complete and partial remission at 24-month follow-up, respectively. Patients with LN class III achieved complete remission more often than those with classes IV or V (mixed and pure). Only 89 of 351 patients maintained stable complete kidney remission from the 6th to 24th months of follow-up. eGFR ≥ 90 ml/min/1.73 m2 at diagnosis and biopsy class III were predictive of stable kidney remission. The youngest and the oldest age quartiles (2y-9y, 5m) (14y, 2m-18y,2m) showed lower rates of stable remission (17% and 20.7%, respectively) compared to the two other age groups (29.9% and 33.7%), while there was no difference in gender. No difference in achieving stable remission was found between children who received mycophenolate or cyclophosphamide as induction treatment.

CONCLUSION

Our data show that the rate of complete remission in patients with LN is still not high enough. Severe kidney involvement at diagnosis was the most important risk factor for not achieving stable remission while different induction treatments did not impact outcome. Randomized treatment trials involving children and adolescents with LN are needed to improve outcome for these children. A higher resolution version of the Graphical abstract is available as Supplementary information.

Remission and long-term remission of pediatric-onset systemic lupus erythematosus

Objectives

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with diverse clinical presentations and prognoses. Remission can be achieved with or without glucocorticoid (GC) use, and several recent studies have suggested that long-term remission can be achieved in a small portion of patients. Nevertheless, few studies have investigated remission or long-term remission in the pediatric-onset SLE subgroup. This study analyzed the characteristics and factors associated with long-term remission and GC use in pediatric-onset SLE.

Methods

We enrolled 226 patients aged <18 years who received a diagnosis of SLE between January 2006 and December 2016. Three remission condition groups were defined: (A) complete remission, (B) clinical remission off GCs, and (C) clinical remission on GCs. Long-term remission was defined as remission for more than 5 years. We analyzed the treatment durations before remission, durations of remission, and risk factors for non-remission with persistent GC use.

Results

During follow-up, 8 patients (3.5%) achieved complete remission, 35 patients (15.5%) achieved clinical remission off GCs, and 93 patients (41.2%) achieved clinical remission on GCs. In groups A, B, and C, 12.5%, 68.6%, and 65.6% of patients, respectively, remained in remission for >1 year.

Conclusion

This study assessed remission of pediatric-onset SLE. Up to 60.2% of patients had clinical remission after treatment, and 19% of patients achieved remission off GCs. Long-term remission is rarer in pediatric-onset SLE than in adult-onset SLE.

Lupus Nephritis in Children: Novel Perspectives

Childhood-onset systemic lupus erythematosus is an inflammatory and autoimmune condition characterized by heterogeneous multisystem involvement and a chronic course with unpredictable flares. Kidney involvement, commonly called lupus nephritis, mainly presents with immune complex-mediated glomerulonephritis and is more frequent and severe in adults. Despite a considerable improvement in long-term renal prognosis, children and adolescents with lupus nephritis still experience significant morbidity and mortality. Moreover, current literature often lacks pediatric-specific data, leading clinicians to rely exclusively on adult therapeutic approaches. This review aims to describe pediatric lupus nephritis and provide an overview of the novel perspectives on the pathogenetic mechanisms, histopathological classification, therapeutic approach, novel biomarkers, and follow-up targets in children and adolescents with lupus nephritis.

Presentation and outcome of pediatric lupus nephritis from a large single centre contemporary cohort in Eastern India

BACKGROUND

We present clinical, biochemical, and histopathological characteristics and treatment outcomes of biopsy proven childhood lupus nephritis (LN) from a low/middle income setting treated in the current era of increased use of Mycophenolate Mofetil (MMF) and biologics.

METHODS

Retrospective observational study of children (1-18 years) with biopsy proven LN treated from 01.01.2010 to 31.01.2020.

RESULTS

60 children met our inclusion criteria (80%, n = 48 were females). The median age at diagnosis was 11 (IQR: 9-12) years. The most common extra-renal manifestation was mucocutaneous (n = 54, 90%) and the most common kidney manifestation was edema (n = 50, 83.3%). The median 24-h urinary protein excretion was 1117.8 (IQR: 795.4-1941.7) mg/m2/day with 67% (n = 40) having nephrotic range proteinuria (>1000 mg/m2/day). 75% (n = 45) children had eGFR <90 mL/min/1.73 m2 (median eGFR = 71; IQR: 56-90 mL/min/1.73 m2). Anti-Nuclear Antibody was positive in all, both complement three and four were low in 82% (n = 49) and anti-double stranded DNA antibodies were positive in 63% (n = 38). 85% (n = 51) had proliferative LN with majority being class IV (57%, n = 34). All children received steroids for induction therapy. MMF was given as the sole induction agent in 48% (n = 29) and cyclophosphamide in 27% (n = 16). Rituximab was added in 17% (n = 10) as a rescue agent. Median follow up duration was 50 (IQR: 28-82) months. Six children (10%) died as a result of serious infections and none of them had shown complete response (CR). Out of the 52 children who had a follow up duration of at least 2 years, CR was achieved in 46 children (88%) and partial response (PR) or no response (NR) in three children (6%) each. Although children who were in CR/PR at last follow up had lower proteinuria, higher eGFR, and lower histopathology activity index at onset; low numbers in the NR group precluded us from subjecting them to any statistical correlation tests. 36% (n = 22) of children developed 36 episodes of renal flares with overall incidence of 0.14/person-year.

CONCLUSION

Our study on a contemporary cohort of childhood LN highlights the importance of achieving CR and its feasibility.

Clinicopathological, Immunological, and Laboratory Parameters of Childhood Lupus Nephritis: A Study from Northeast India

Background Lupus nephrtis in children is associated with high morbidity and mortality. The incidence of childhood systemic lupus erythematosus (SLE) ranges from 3.3 to 8.8/100000 children with a higher Asian preponderance. The predominance of SLE in female pediatric patients increases gradually with age to the values observed in adults. Objectives  To assess the clinical, immunological, and histopathological spectrum of childhood lupus nephritis in northeast India and explore the relationship between clinical, biochemical, serological, and histopathological findings. Materials and Methods  A retrospective descriptive study was performed over 8 years. Histopathology slides were reviewed by two pathologists, whereas other details were collected from patients' records. Statistical Analysis  Statistical analysis was based on the chi-square test and a p -value < 0.05 was considered statistically significant. Results  Fifty-three cases of lupus nephritis were included in the study. The patients' age ranged from 5 to 18 years with a mean age of 14.5 years and a female: male ratio of 6.5:1. Edema and hypertension were the commonest clinical presentations, whereas proteinuria was the commonest presenting laboratory parameter. Amongst all the immunological markers, dsDNA was the commonest. Histopathologically, predominantly study population belonged to class IV lupus nephritis. The patients with class IV showed a statistically significant correlation with proteinuria and hematuria at the time of diagnosis. Immunological markers, namely, ANA and anti-ds-DNA positivity were significantly associated with advanced renal histopathology. Conclusion  cSLE in northeast India presents mostly as Class IV LN presenting mostly with deranged laboratory parameters and preponderance of various immunological markers and clinical presentations.

Identification of potent target and its mechanism of action of Tripterygium wilfordii Hook F in the treatment of lupus nephritis

AIM

The Chinese anti-rheumatic herbal remedy Tripterygium wilfordii Hook F (TWHF) has been widely shown to be effective in treating lupus nephritis (LN), but the therapeutic targets and mechanisms of action are still unclear. In this study, we aimed to combine mRNA expression profile analysis and network pharmacology analysis to screen the pathogenic genes and pathways involved in LN and to explore the potential targets of TWHF in the treatment of LN.

METHODS

The mRNA expression profiles of LN patients were used to screen differentially expressed genes (DEGs) and to predict associated pathogenic pathways and networks via the Ingenuity Pathway Analysis database. Through molecular docking, we predicted the mechanism by which TWHF interacts with candidate targets.

RESULTS

A total of 351 DEGs were screened from the glomeruli of LN patients and were mainly concentrated in the role of pattern recognition receptors in the recognition of bacteria and viruses and interferon signaling pathways. A total of 130 DEGs were screened from the tubulointerstitium of LN patients, which were concentrated in the interferon signaling pathway. TWHF might be effective in treating LN by hydrogen bonding to regulate the functions of 24 DEGs (including HMOX1, ALB, and CASP1), which are mainly concentrated in the B-cell signaling pathway.

CONCLUSION

The mRNA expression profile of renal tissue from LN patients revealed a large number of DEGs. TWHF has been shown to interact with the DEGs (including HMOX1, ALB and CASP1) through hydrogen bonding to treat LN.

Renal C4d is a potential biomarker of disease activity and severity in pediatric lupus nephritis patients

Background

Systemic lupus erythematosus (SLE), a multisystemic autoimmune disease, is very aggressive in pediatric-onset patients as they are prone to develop lupus nephritis (LN). Although renal C4d positivity is correlated with the activity of renal disease and SLE in adult-onset LN patients, available information for pediatric-onset patients is limited.

Methods

To evaluate the potential diagnostic significance of renal C4d staining in pediatric LN patients, we retrospectively detected C4d staining by immunohistochemistry on renal biopsy specimens from 58 pediatric LN patients. The clinical and laboratory data at the time of the kidney biopsy and the renal disease activity of histological injury were analyzed according to the C4d staining status.

Results

Glomerular C4d (G-C4d)-positive staining was detected in all 58 cases of LN. Patients with a G-C4d score of 2 displayed more severe proteinuria than those with a G-C4d score of 1 (24-h urinary protein: 3.40 ± 3.55 g vs. 1.36 ± 1.24 g, P < 0.05). Peritubular capillary C4d (PTC-C4d) positivity was found in 34 of 58 LN patients (58.62%). The PTC-C4d-positive patient groups (patients with a PTC-C4d score of 1 or 2) had higher serum creatinine and blood urea nitrogen levels as well as renal pathological activity index (AI) and SLE disease activity index (SLEDAI) scores; however, they had lower serum complement C3 and C4 levels compared to PTC-C4d-negative patients (P < 0.05). In addition, there was positive tubular basement membrane C4d (TBM-C4d) staining in 11 of 58 LN patients (18.96%), and a higher proportion of TBM-C4d-positive patients than TBM-C4d-negative patients (63.63% vs. 21.27%) had hypertension.

Conclusion

Our study revealed that G-C4d, PTC-C4d, and TMB-C4d were positively correlated with proteinuria, disease activity and severity, and hypertension, respectively, in pediatric LN patients. These data suggest that renal C4d is a potential biomarker for disease activity and severity in pediatric LN patients, providing insights into the development of novel identification and therapeutic approaches for pediatric-onset SLE with LN.

Autoantibody-based subgroups and longitudinal seroconversion in juvenile-onset systemic lupus erythematosus

OBJECTIVE

To explore the clinical value of autoantibody-based subgroup framework and the trend of autoantibody fluctuation in juvenile-onset SLE (JSLE).

METHODS

Eighty-seven patients with JSLE were retrospectively collected and divided into subgroups via a two-step cluster based on the status of nine autoantibodies (double-stranded-DNA (dsDNA), nucleosome, histone, ribosomal P protein, Smith (Sm), u1-ribonucleoprotein (RNP), Sjögren's syndrome antigen A (SSA)/Ro52, SSA/Ro60, Sjögren's syndrome antigen B (SSB)/La). The final model selected in this study was based on adequate goodness of fit of the Silhouette coefficient and clinical interpretability. Clinical manifestations, organ involvements and disease activity were compared among the subgroups. Fluctuation in autoantibody status was also collected and analysed. Flare-free survival rates of the patients with positive/negative seroconversion and patients without seroconversion were studied by the Kaplan-Meier method and compared using a log-rank test.

RESULTS

Two clusters were identified: subgroup 1 (positive anti-Sm/RNP group) and subgroup 2 (negative anti-Sm/RNP group). There were more lupus nephritis (LN) and neuropsychiatric SLE (NPSLE) cases in subgroup 1 than in subgroup 2. Patients in subgroup 1 exhibited higher SLE Disease Activity Index scores compared with those in subgroup 2. Furthermore, anti-ribosomal P protein (61.1%), anti-nucleosome (58.3%) and anti-dsDNA (54%) were most commonly positive autoantibodies. A progressive decrease in the frequency of patients with positive results was demonstrated during the follow-up years. The decrease was notable for anti-dsDNA, anti-nucleosome and anti-ribosomal P protein (remaining 27.27%, 38.89% and 45.00% positive in the fifth year, respectively). While for those negative at baseline diagnosis, the decrease in the frequency of negative results was progressive but modest. Kaplan-Meier curve showed that the flare-free survival of patients with positive seroconversion was significantly lower than those without seroconversion and those with negative seroconversion (p<0.001).

CONCLUSIONS

In children with SLE, subgroups based on autoantibody profile can be applied to differentiate phenotypes and disease activity. Two important organ involvements, LN and NPSLE, are more common in patients with positive anti-Sm/RNP autoantibodies. Positive seroconversion may provide a valuable perspective for assessing flare, and it is worthwhile to retest the array of autoantibodies during follow-up.

Management and outcomes in children with lupus nephritis in the developing countries

BACKGROUND

Lupus nephritis (LN) has variable prevalence, severity, and outcomes across the world.

OBJECTIVES

This review compares the outcomes of childhood LN in low- and middle-income countries (LMICs) and high-income countries (HICs) and aims to summarize long-term outcomes of pediatric LN from LMICs.

DATA SOURCES

A systematic literature search, conducted in PubMed, EMBASE, and Cochrane database in the last 30-years from January 1992, published in the English language, identified 113 studies including 52 from lower (n = 1336) and upper MICs (n = 3014).

STUDY ELIGIBILITY CRITERIA

Cohort studies or randomized controlled trials, of patients ≤ 18 years of age (or where such data can be separately extracted), with > 10 patients with clinically or histologically diagnosed LN and outcomes reported beyond 12 months were included.

PARTICIPANTS AND INTERVENTIONS

Patients ≤ 18 years of age with clinically or histologically diagnosed LN; effect of an intervention was not measured.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two authors independently extracted data. We separately analyzed studies from developed countries (high income countries; HIC) and developing countries (LMICs). Middle-income countries were further classified as lower and upper MICs. Meta-analyses of data were performed by calculating a pooled estimate utilizing the random-effects model. Test for heterogeneity was applied using I² statistics. Publication bias was assessed using funnel plots.

RESULTS

Kidney remission was similar across MICs and HICs with 1-year pooled complete remission rates of 59% (95% CI 51-67%); one third of patients had kidney flares. The pooled 5-year survival free of stage 5 chronic kidney disease (CKD5) was lower in MICs, especially in lower MICs compared to HICs (83% vs. 93%; P = 0.002). The pooled 5-year patient survival was significantly lower in MICs than HICs (85% vs. 94%; P < 0.001). In patients with class IV LN, the 5-and 10-year respective risk of CKD5 was 14% and 30% in MICs; corresponding risks in HICs were 8% and 17%. Long-term data from developing countries was limited. Sepsis (48.8%), kidney failure (14%), lupus activity (18.1%), and intracranial hemorrhage/infarct (5.4%) were chief causes of death; mortality due to complications of kidney failure was more common in lower MICs (25.6%) than HICs (6.4%).

LIMITATIONS

The review is limited by heterogenous approach to diagnosis and management that has changed over the period spanning the review. World Bank classification based on income might not correlate with the standards of medical care. The overall quality of evidence is low since included studies were chiefly retrospective and single center.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Challenges in LMICs include limited access to pediatric nephrology care, dialysis, increased risk of infection-induced mortality, lack of frequent monitoring, and non-compliance due to cost of therapy. Attention to these issues might update the existing data and improve patient follow-up and outcomes.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO 2022 number: CRD42022359002, available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022359002.

Lupus low disease activity state as a treatment target for pediatric patients with lupus nephritis

BACKGROUND

Lupus low disease activity state (LLDAS) is a treatment target for patients with SLE and is associated with decreased risk for severe flare and new damage. We investigated the utility of the achievement of LLDAS in children with lupus nephritis and whether attainment of LLDAS is associated with more favorable outcomes.

METHODS

Data of children, diagnosed with biopsy-proven lupus nephritis between January 2012 and December 2020, were retrospectively analyzed.

RESULTS

For patients who did not achieve LLDAS after initial treatment (first 6 months), presence of autoimmune hemolytic anemia (62% vs. 18%, p = 0.047), anti-Sm (85% vs. 18%, p = 0.003) and anti-dsDNA (77% vs. 27%, p = 0.038) antibodies, proliferative lupus nephritis (77% vs. 27%, p = 0.038), and hypertension (69% vs. 9%, p = 0.005) at onset were more frequently encountered. Also, a lower rate of complete kidney response (43% vs. 100%, p = 0.005) and a higher rate of hypertension (86% vs. 13%, p = 0.002) were observed in patients who did not achieve LLDAS-50, defined as being in LLDAS at least 50% of the observation time. Attainment of both LLDAS after initial treatment and LLDAS-50 were associated with lower rates of kidney flare (p = 0.001 and p = 0.002, respectively) and damage accrual (p = 0.007 and p = 0.02, respectively) through the observation period.

CONCLUSIONS

LLDAS is an attainable treatment target for children with lupus nephritis and associated with lower rates of kidney flare and damage. Presence of hematologic involvement, hypertension, and proliferative lupus nephritis at onset adversely influenced the early achievement of LLDAS. A higher resolution version of the Graphical abstract is available as Supplementary information.

Bilateral neuroretinitis and membranous lupus nephritis: 2 infrequent manifestations in juvenile lupus

Fifteen-year-old female patient, previously healthy, referred to our center for presenting abdominal pain, vomiting, diarrhea, malar erythema, palpebral and lower limb edema, arthralgia, morning stiffness and bilateral blurred vision. Laboratory and imaging studies together with the clinic allowed the diagnosis of nephrotic syndrome secondary to systemic lupus erythematosus. Ophthalmology examination revealed a visual acuity of 8/10 in both eyes and bilateral disc edema with partial macular star, findings compatible with bilateral neuroretinitis. Renal biopsy established the diagnosis of membranous lupus nephritis. Immunosuppressive treatment was started, obtaining gradual clinical improvement. Although systemic lupus erythematosus with membranous lupus nephritis and neuroretinitis is a very infrequent association, when faced with a patient with bilateral neuroretinitis, we must consider systemic lupus erythematosus within the differential diagnoses.

Identification of biomarkers that predict renal flare in childhood-onset lupus nephritis with mycophenolate acid

BACKGROUND

Children-onset lupus nephritis (cLN) occurs > 50 % of patients with systemic lupus erythematosus. Mycophenolic acid (MPA) is the first-line agent for the induction and maintenance treatment of LN. This study was to explore the predictors of renal flare in cLN.

METHODS

Data from 90 patients were included in population pharmacokinetic (PK) models to predict MPA exposure. Cox regression models and restricted cubic spline were performed in 61 patients to identify the risk factors for renal flare, baseline clinical characteristics and MPA exposures as potential covariates.

RESULTS

PK best fitted a two-compartment model of first-order absorption and linear elimination, with delayed absorption. Clearance increased with weight and immunoglobulin G (IgG), but decreased with albumin and serum creatinine. During follow-up of 1040 (658-1359) days, 18 patients experienced a renal flare, after a median time of 932.5 (663.5-1316) days. Each 1-mg·h/L increase of MPA-AUC was associated with a 6 % decreased risk of an event (HR = 0.94; 95 % CI: 0.90-0.98), while IgG significantly increased this risk (HR = 1.17; 95 % CI: 1.08-1.26). ROC analysis showed that MPA-AUC_0-12h < 35 mg·h/L and IgG > 17.6 g/L had a good prediction of renal flare. Of restricted cubic spline, the risk of renal flares decreased with higher MPA exposure but reached a plateau when AUC_0-12h > 55 mg·h/L, while substantially increases when IgG is > 18.2 g/L.

CONCLUSIONS

Monitoring MPA exposure together with IgG could be very useful during clinical practice to identify patients with a potential high risk of renal flare. This early risk assessment would allow for the treat-to-target and tailored medicine.

A Preliminary Predictive Model for Proliferative Lupus Nephritis in Juvenile Systemic Lupus Erythematosus

Proliferative lupus nephritis, which is diagnosed by renal biopsy, has significant impact on the treatment choices and long-term prognosis of juvenile SLE (jSLE). Renal biopsies are however not always possible or available, thus leading to an ongoing search for alternative biomarkers. This study aimed to develop a clinical predictive machine learning model using routine standard parameters as an alternative tool to evaluate the probability of proliferative lupus nephritis (ISN/RPS Class III or IV). Data were collected retrospectively from jSLE patients seen at Selayang Hospital from 2004 to 2021. A total of 22 variables including demographic, clinical and laboratory features were analyzed. A recursive feature elimination technique was used to identify factors to predict pediatric proliferative lupus nephritis. Various models were then used to build predictive machine learning models and assessed for sensitivity, specificity and accuracy. There were 194 jSLE patients (165 females), of which 111 had lupus nephritis (54 proliferative pattern). A combination of 11 variables consisting of gender, ethnicity, fever, nephrotic state, hypertension, urine red blood cells (RBC), C3, C4, duration of illness, serum albumin, and proteinuria demonstrated the highest accuracy of 79.4% in predicting proliferative lupus nephritis. A decision-tree model performed the best with an AROC of 69.9%, accuracy of 73.85%, sensitivity of 78.72% and specificity of 61.11%. A potential clinically useful predictive model using a combination of 11 non-invasive variables to collectively predict pediatric proliferative lupus nephritis in daily practice was developed.

Consensus document of the Spanish Group for the Study of the Glomerular Diseases (GLOSEN) for the diagnosis and treatment of lupus nephritis

A significant number of patients with systemic lupus erythematosus (between 20% and 60% according to different reported series) develop lupus nephritis in the course of its evolution, which directly influences their quality of life and vital prognosis. In recent years, the greater knowledge about the pathogenesis of systemic lupus and lupus nephritis has allowed relevant advances in the diagnostic approach and treatment of these patients, achieving the development of drugs specifically aimed at blocking key pathogenic pathways of the disease. Encouragingly, these immunomodulatory agents have shown in well-powered, randomized clinical trials good clinical efficacy in the medium-term, defined as proteinuria remission and preservation of kidney function, with an acceptable safety profile and good patient tolerability. All this has made it possible to reduce the use of corticosteroids and other potentially more toxic therapies, as well as to increase the use of combined therapies. The present consensus document carried out by the Glomerular Diseases Working Group of the Spanish Society of Nephrology (GLOSEN), collects in a practical and summarized, but rigorous way, the best currently available evidence about the diagnosis, treatment, and follow-up of lupus nephritis patients, including cases of special situations, with the main objective of providing updated information and well-founded clinical recommendations to treating physicians, to improve the diagnostic and therapeutic approach to our patients.

Chronic kidney disease in patients with childhood-onset systemic lupus erythematosus

BACKGROUND

Lupus nephritis (LN) is a frequent manifestation of childhood-onset systemic lupus erythematosus (cSLE) with a potential risk for kidney failure and poor outcomes. This study aimed to evaluate stages III, IV, and V of chronic kidney disease (CKD) and investigate risk factors for CKD in cSLE patients.

METHODS

We performed a nationwide observational cohort study in 27 pediatric rheumatology centers, including medical charts of 1528 cSLE patients. Data were collected at cSLE diagnosis, during follow-up, and at last visit or death, between September 2016 and May 2019.

RESULTS

Of 1077 patients with LN, 59 (5.4%) presented with CKD, 36/59 (61%) needed dialysis, and 7/59 (11.8%) were submitted for kidney transplantation. After Bonferroni's correction for multiple comparisons (p < 0.0013), determinants associated with CKD were higher age at last visit, urinary biomarker abnormalities, neuropsychiatric involvement, higher scores of disease activity at last visit and damage index, and more frequent use of methylprednisolone, cyclosporine, cyclophosphamide, and rituximab. In the regression model analysis, arterial hypertension (HR = 15.42, 95% CI = 6.12-38.83, p ≤ 0.001) and biopsy-proven proliferative nephritis (HR = 2.83, 95%CI = 1.70-4.72, p ≤ 0.001) increased the risk of CKD, while children using antimalarials had 71.0% lower CKD risk ((1.00-0.29) × 100%) than children not using them. The Kaplan-Meier comparison showed lower survival in cSLE patients with biopsy-proven proliferative nephritis (p = 0.02) and CKD (p ≤ 0.001).

CONCLUSIONS

A small number of patients manifested CKD; however, frequencies of dialysis and kidney transplantation were relevant. This study reveals that patients with cSLE with hypertension, proliferative nephritis, and absence of use of antimalarials exhibited higher hazard rates of progression to CKD. A higher resolution version of the Graphical abstract is available as Supplementary information.

Long-Term Outcomes of Children and Adolescents With Biopsy-Proven Childhood-Onset Lupus Nephritis

Introduction

Long-term data pertaining to childhood-onset lupus nephritis (cLN) remain extremely scarce.

Methods

We conducted a retrospective cohort study of biopsy-proven cLN with onset age <18 years diagnosed from 2001 to 2020 to ascertain the long-term patient and kidney survival rates, and the incidence of advanced chronic kidney disease (CKD) (estimated glomerular filtration rate [eGFR] <60 ml/min per 1.73 m²).

Results

A total of 92 subjects (78 female; age 13.7 ± 3.3 years; all Chinese) were included, with follow-up duration of 10.3 years (interquartile range, 5.8-15.9). Of these, 83 children (90%) had proliferative lupus nephritis (LN) (Class III/IV ± V). Mycophenolate was used for induction in 36%, whereas 34% received cyclophosphamide (CYC); 55% received mycophenolate as maintenance immunosuppression. The rates of complete remission (CR) and partial remission (PR) at 6 months and 12 months, respectively, were 65% and 20% and 78% and 8%. Two patients died (mortality rate 2.1/1000 patient-years), with a standardized mortality ratio of 22.3. Three patients (3.2%) developed end-stage kidney disease (ESKD), and advanced CKD occurred in 5 patients (5.4%). Survival rates without advanced CKD, ESKD, or death were 96.7%, 94.2%, 92.7%, 83.2% and 83.2% at 1 year, 5 years, 10 years, 15 years, and 20 years, respectively. Multivariate analysis revealed that severe kidney failure necessitating dialysis at presentation (adjusted hazard ratio 37.7, 95% confidence interval [CI] 4.0-355.6, P = 0.002), nonresponse (NR) after 12 months of treatment (adjusted hazard ratio 11.2, 95% CI 2.3-54.9, P = 0.003), and multiple nephritis flares (adjusted hazard ratio 2.6, 95% CI 1.1-6.2, P = 0.03) were predictive of advanced CKD, ESKD, or death. Other adverse outcomes included infections (2.9 episodes/100 patient-years), osteopenia (32%), hypertension (17%), short stature (14%), and avascular necrosis (7%).

Conclusion

The long-term outcomes of cLN appeared to have improved in the present era with effective immunosuppression, cautious drug tapering, and assurance of medication adherence. There is still an unacceptably high prevalence of adverse outcomes.

Acute kidney injury requiring kidney replacement therapy in childhood lupus nephritis: a cohort study of the Pediatric Nephrology Research Consortium and Childhood Arthritis and Rheumatology Research Alliance

BACKGROUND

Acute kidney injury (AKI) is common in lupus nephritis (LN) and a risk factor for development of chronic kidney disease. In adults with LN, AKI severity correlates with the incidence of kidney failure and patient survival. Data on AKI outcomes in children with LN, particularly those requiring kidney replacement therapy (KRT), are limited.

METHODS

A multicenter, retrospective cohort study was performed in children diagnosed between 2010 and 2019 with LN and AKI stage 3 treated with dialysis (AKI stage 3D). Descriptive statistics were used to characterize demographics, clinical data, and kidney biopsy findings; treatment data for LN were not included. Logistic regression was used to examine the association of these variables with kidney failure.

RESULTS

Fifty-nine patients (mean age 14.3 years, 84.7% female) were identified. The most common KRT indications were fluid overload (86.4%) and elevated blood urea nitrogen/creatinine (74.6%). Mean follow-up duration was 3.9 ± 2.9 years. AKI recovery without progression to kidney failure occurred in 37.3% of patients. AKI recovery with later progression to kidney failure occurred in 25.4% of patients, and there was no kidney recovery from AKI in 35.6% of patients. Older age, severe (> 50%) tubular atrophy and interstitial fibrosis, and National Institutes of Health (NIH) chronicity index score > 4 on kidney biopsy were associated with kidney failure.

CONCLUSIONS

Children with LN and AKI stage 3D have a high long-term risk of kidney failure. Severe tubular atrophy and interstitial fibrosis at the time of AKI, but not AKI duration, are predictive of kidney disease progression. A higher resolution version of the Graphical abstract is available as Supplementary information.

Tertiary lymphoid tissues in kidney diseases: a perspective for the pediatric nephrologist

Chronic kidney disease (CKD) is a major public health problem worldwide. In the pediatric population, CKD is also an important health issue because it causes several comorbid conditions that can have long-term consequences beyond the pediatric age. Chronic inflammation is a common pathological feature of CKD, irrespective of etiology, and leads to maladaptive repair and kidney dysfunction. Tertiary lymphoid tissues (TLTs) are ectopic lymphoid structures that develop in non-lymphoid organs under chronic inflammation caused by pathological conditions, including infections, autoimmune diseases, and cancers. TLTs in the kidneys have been poorly researched due to the lack of an animal model. We have recently found that, in aged but not young mice, TLTs develop in multiple kidney injury models, and the analysis of age-dependent TLTs has brought about several novel insights into the development and pathogenic impacts of TLTs in the kidney. Age-dependent TLT formation is also observed in human kidneys. In addition to aged kidneys, TLT development is also reported in several human kidney diseases including kidney allografts, lupus nephritis, and IgA nephropathy in both adults and children. In this review, we describe the novel findings on TLTs in the kidney obtained mainly from the analysis of age-dependent TLTs and discuss the clinical relevance of TLTs in kidney diseases.

The long-term outcome of New Zealand Maori and Pacific Island children diagnosed with childhood onset lupus nephritis

OBJECTIVE

To determine the long-term outcome of Maori and Pacific Island children diagnosed with childhood onset lupus nephritis.

METHOD

A chart review was conducted of children diagnosed with biopsy proven lupus nephritis seen by the Starship Hospital and Kidz First paediatric rheumatology and/or Starship renal services between January 1992 and January 2018. Baseline and follow-up kidney histology, adherence and response to therapy including partial or full renal remission, refractory disease, end-stage kidney disease (ESKD) and mortality were determined.

RESULTS

In a New Zealand cohort of 42 with childhood onset lupus nephritis, Maori and Pacific Island children were significantly more likely to develop class 4 lupus nephritis (RR (95% CI), 11.3 (3.84-49.9), p < 0.0001), demonstrate medication nonadherence (RR (95% CI) 12.4 (3.48-85.7), p < 0.0001) and experience end stage kidney disease (RR (95% CI) 15.7 (2.97-389.3), p = 0.0003) and mortality (RR (95% CI) 11.1 (1.91-280.1), p = 0.005) compared to non-Maori and Pacific Island children. In addition, Maori children with childhood onset lupus nephritis developed chronic histological changes significantly more rapidly than Pacific or Asian children (p = 0.038).

CONCLUSION

Lupus nephritis is more common among Maori and Pacific Island children in New Zealand associated with a significant incidence of end stage kidney disease and mortality, with some Maori children developing rapid histologic disease progression.

Urine ALCAM, PF4 and VCAM-1 Surpass Conventional Metrics in Identifying Nephritis Disease Activity in Childhood-Onset Systemic Lupus Erythematosus

Objectives

Serial kidney biopsy for repeat evaluation and monitoring of lupus nephritis (LN) in childhood-onset Systemic Lupus Erythematosus (cSLE) remains challenging, thus non-invasive biomarkers are needed. Here, we evaluate the performance of ten urine protein markers of diverse nature including cytokines, chemokines, and adhesion molecules in distinguishing disease activity in cSLE.

Methods

Eighty-four pediatric patients meeting ≥4 ACR criteria for SLE were prospectively enrolled for urine assay of 10 protein markers normalized to urine creatinine, namely ALCAM, cystatin-C, hemopexin, KIM-1, MCP-1, NGAL, PF-4, Timp-1, TWEAK, and VCAM-1 by ELISA. Samples from active renal (LN) and active non-renal SLE patients were obtained prior to onset/escalation of immunosuppression. SLE disease activity was evaluated using SLEDAI-2000. 59 patients had clinically-active SLE (SLEDAI score ≥4 or having a flare), of whom 29 patients (34.5%) were classified as active renal, and 30 patients (35.7%) were active non-renal. Twenty-five healthy subjects were recruited as controls.

Results

Urine concentrations of ALCAM, KIM-1, PF4 and VCAM-1 were significantly increased in active LN patients versus active non-renal SLE, inactive SLE and healthy controls. Five urine proteins differed significantly between 2 (hemopexin, NGAL, MCP1) or 3 (Cystatin-C, TWEAK) groups only, with the highest levels detected in active LN patients. Urine ALCAM, VCAM-1, PF4 and hemopexin correlated best with total SLEDAI as well as renal-SLEDAI scores (p < 0.05). Urine ALCAM, VCAM-1 and hemopexin outperformed conventional laboratory measures (anti-dsDNA, complement C3 and C4) in identifying concurrent SLE disease activity among patients (AUCs 0.75, 0.81, 0.81 respectively), while urine ALCAM, VCAM-1 and PF4 were the best discriminators of renal disease activity in cSLE (AUCs 0.83, 0.88, 0.78 respectively), surpassing conventional biomarkers, including proteinuria. Unsupervised Bayesian network analysis based on conditional probabilities re-affirmed urine ALCAM as being most predictive of active LN in cSLE patients.

Conclusion

Urinary ALCAM, PF4, and VCAM-1 are potential biomarkers for predicting kidney disease activity in cSLE and hold potential as surrogate markers of nephritis flares in these patients.

Characteristics of childhood-onset systemic lupus erythematosus in pregnancy and its association with pregnancy outcomes: a retrospective comparative cohort study

BACKGROUND

Disease situations are more aggressive in patients with childhood-onset systemic lupus erythematosus (cSLE) than in those with adult-onset SLE (aSLE). However, information on pregnant women with cSLE and its association with pregnancy outcomes is limited. This study aimed to compare pregnancies in patients with cSLE vs. aSLE, and further analyse the characteristics of cSLE in pregnant women and explore its association with adverse pregnancy outcomes.

METHODS

Altogether, data of 167 pregnancies from 150 women, including 22 pregnancies with cSLE and 145 pregnancies with aSLE, were retrospectively analysed. Characteristics and disease activity were compared between the cSLE and aSLE groups during pregnancy. Associations between cSLE and the risk of active SLE (SLEPDAI > 4), active lupus nephritis (LN), and adverse pregnancy outcomes were analysed using logistic regression.

RESULTS

The cSLE group had a higher incidence of active SLE (12/22 vs. 30/145, P = 0.001) and active LN (11/22 vs. 26/145, P = 0.001) than the aSLE group. In the multivariable analysis, cSLE was a risk factor for active SLE and active LN during pregnancy, with ORs of 4.742 (95%CI 1.678-13.405, P = 0.003) and 4.652 (95%CI 1.630-13.279, P = 0.004), respectively. No significant association between cSLE and the risk of composite adverse gestational outcomes was identified after sequentially adjusting pre-pregnancy characteristics and pregnancy factors (P > 0.05).

CONCLUSION

Disease activity of women with cSLE in pregnancy was more aggressive than that of women with aSLE, which was similar to the characteristics of non-pregnant women with SLE. cSLE might have indirect effects on the risk of adverse pregnancy outcomes through LN and active disease. Therefore, closely monitoring patients with cSLE during pregnancy is crucial.

Renal manifestations of paediatric systemic lupus erythematosus

PURPOSE OF REVIEW

Systemic lupus erythematosus is a lifelong, multisystemic disease. Around a fifth of patients present during childhood. Children are recognized to have a more active disease course with more renal involvement (lupus nephritis) when compared with adults. This review article summarizes the current literature surrounding the management of paediatric lupus nephritis.

RECENT FINDINGS

International recommendations agree that active, proliferative forms of lupus nephritis are treated with a period of intense induction therapy aimed at inducing remission followed by maintenance immunosuppressive therapy for at least 3 years. Complete response rates in lupus nephritis remain inadequate, in the region of 40-60%, and disease flares are common. Revised histological classification have been proposed but they are yet to be adopted in clinical practice. Lupus nephritis progresses to chronic kidney disease (CKD) stage 5 (kidney failure) in more than 10% of patients within 10 years however the rates of CKD stages 1-4 remain largely unknown. Current trials are focused on the use of biologic agents as adjuncts to current therapy.

SUMMARY

There is an urgent need for better outcomes in paediatric lupus nephritis. The use of biomarkers to monitor lupus nephritis and scientific studies to improve our understanding of the pathogenesis offer hope of improved outcomes.

Pharmacokinetics of mycophenolic acid and external evaluation of two limited sampling strategies of drug exposure in patients with juvenile systematic lupus erythematosus

INTRODUCTION

Mycophenolate mofetil (MMF), a pro-drug of mycophenolic acid (MPA), has become a major therapeutic option in juvenile systemic lupus erythematosus (jSLE). Monitoring MPA exposure using area under curve (AUC) has proved its value to increase efficacy and safety in solid organ transplantation both in children and adults, but additional data are required in patients with autoimmune diseases. In order to facilitate MMF therapeutic drug monitoring (TDM) in children, Bayesian estimators (BE) of MPA AUC_0-12 h using limited sampling strategies (LSS) have been developed. Our aim was to conduct an external validation of these LSS using rich pharmacokinetics and compare their predictive performance.

METHODS

Pharmacokinetic blood samples were collected from jSLE treated by MMF and MPA plasma concentrations were determined using high-performance liquid chromatography system with ultraviolet detection (HPLC-UV). Individual AUC_0-12 h at steady state was calculated using the trapezoid rule and compared with two LSS: (1) ISBA, a two-stage Bayesian approach developed for jSLE and (2) ADAPT, a non-linear mixed effects model with a parametric maximum likelihood approach developed with data from renal transplanted adults.

RESULTS

We received 41 rich pediatric PK at steady state from jSLE and calculated individual AUC_0-12 h. The external validation MPA AUC_0-12 h was conducted by selecting the concentration-time points adapted to ISBA and ADAPT: (1) ISBA showed good accuracy (bias: - 0.8 mg h/L), (2) ADAPT resulted in a bias of 6.7 mg L/h. The corresponding relative root mean square prediction error (RSME) was 23% and 43% respectively.

CONCLUSION

According to our external validation of two LSS of drug exposure, the ISBA model is recommended for Bayesian estimation of MPA AUC_0-12 h in jSLE. In the literature focusing on MMF TDM, an efficacy cut-off for MPA AUC_0-12 h between 30 and 45 mg h/L is proposed in jSLE but this requires additional validation.

Relationship between Blood Lipid Profiles and Risk of Lupus Nephritis in Children

OBJECTIVE

Systemic lupus erythematosus (SLE) is a relatively common rheumatic disease in children. The characteristics of blood lipid metabolism in children with LN are little reported. This study aimed to explore the relationship between blood lipid profiles and the risk of lupus nephritis (LN) in children.

METHODS

A total of 134 children with newly diagnosed SLE were divided into LN and non-LN groups according to pathological renal biopsy results. Clinical manifestations and blood lipid profiles were analyzed and compared between the two groups, and the relationships between blood lipid profiles and risk of LN were evaluated.

RESULTS

The positivity rate of an anti-dsDNA antibody and an SLE disease activity index (SLEDAI) were significantly increased, and C3 and C4 levels were significantly reduced in the LN compared with the non-LN group. The overall incidence of dyslipidemia was 79.9%, with a significantly high incidence in the LN group compared with the non-LN group. Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and very LDLC (VLDL-C) were all higher in the LN group than those in the non-LN group. However, there was no significant difference in high-density lipoprotein cholesterol (HDL-C) between the two groups. The blood lipid levels were positively correlated with 24-hour urine protein quantification, urea, creatinine, uric acid, urinary IgG, urinary microalbumin, urinary transferrin, urinary α1 microglobulin, and urinary N-acetyl glucosidase, respectively. Receiver-operating characteristic curves showed that combined detection of TC, TG, LDL-C, and VLDL-C had higher discrimination capacity than that in individual measures. Additionally, increased TC was independently associated with the occurrence of LN.

CONCLUSIONS

Children with LN have significant dyslipidemia. High levels of TC, TG, LDL-C, and VLDL-C are closely related to the occurrence of pLN. Clinical attention should be paid to monitoring and managing blood lipid profiles in children with LN.

Using a Multi-Institutional Pediatric Learning Health System to Identify Systemic Lupus Erythematosus and Lupus Nephritis: Development and Validation of Computable Phenotypes

BACKGROUND AND OBJECTIVES

Performing adequately powered clinical trials in pediatric diseases, such as SLE, is challenging. Improved recruitment strategies are needed for identifying patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Electronic health record algorithms were developed and tested to identify children with SLE both with and without lupus nephritis. We used single-center electronic health record data to develop computable phenotypes composed of diagnosis, medication, procedure, and utilization codes. These were evaluated iteratively against a manually assembled database of patients with SLE. The highest-performing phenotypes were then evaluated across institutions in PEDSnet, a national health care systems network of >6.7 million children. Reviewers blinded to case status used standardized forms to review random samples of cases (n=350) and noncases (n=350).

RESULTS

Final algorithms consisted of both utilization and diagnostic criteria. For both, utilization criteria included two or more in-person visits with nephrology or rheumatology and ≥60 days follow-up. SLE diagnostic criteria included absence of neonatal lupus, one or more hydroxychloroquine exposures, and either three or more qualifying diagnosis codes separated by ≥30 days or one or more diagnosis codes and one or more kidney biopsy procedure codes. Sensitivity was 100% (95% confidence interval [95% CI], 99 to 100), specificity was 92% (95% CI, 88 to 94), positive predictive value was 91% (95% CI, 87 to 94), and negative predictive value was 100% (95% CI, 99 to 100). Lupus nephritis diagnostic criteria included either three or more qualifying lupus nephritis diagnosis codes (or SLE codes on the same day as glomerular/kidney codes) separated by ≥30 days or one or more SLE diagnosis codes and one or more kidney biopsy procedure codes. Sensitivity was 90% (95% CI, 85 to 94), specificity was 93% (95% CI, 89 to 97), positive predictive value was 94% (95% CI, 89 to 97), and negative predictive value was 90% (95% CI, 84 to 94). Algorithms identified 1508 children with SLE at PEDSnet institutions (537 with lupus nephritis), 809 of whom were seen in the past 12 months.

CONCLUSIONS

Electronic health record-based algorithms for SLE and lupus nephritis demonstrated excellent classification accuracy across PEDSnet institutions.