Low disease activity state in juvenile-onset systemic lupus erythematosus

Childhood-Onset Systemic Lupus Erythematosus (cSLE): An International Perspective

PURPOSE OF REVIEW

Childhood-onset systemic lupus erythematosus (cSLE) is a severe and potentially life-threatening chronic autoimmune disease. cSLE is more aggressive and has poorer outcomes than adult-onset disease. The global burden of cSLE is poorly understood, with most publications on cSLE originating from high-resourced settings. The reports from less resourced settings indicate high morbidity and mortality in these populations.

RECENT FINDINGS

In this article, we review the disparities in global access to rheumatology care and research for patients with cSLE. We highlight recent cSLE advances from all regions of the globe. We describe current obstacles to cSLE clinical care and research in all settings. Finally, we propose a path forward for high quality, equitable and accessible care to individuals with cSLE everywhere. Individuals with cSLE are at risk for morbidity and death, yet patients worldwide face challenges to adequate access to care and research. Sustained, collaborative efforts are needed to create pathways to improve care and outcomes for these patients.

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.

Childhood-onset systemic lupus erythematosus: A descriptive and comparative study of clinical, laboratory, and treatment characteristics in two populations

OBJECTIVE

The aim of this study was to characterize childhood-onset systemic lupus erythematosus (SLE) in two large cohorts from Turkey and the United States.

METHODS

Patients diagnosed with childhood-onset SLE who fulfilled the 1997 American College of Rheumatology classification criteria for SLE from four reference centers in Turkey and the University of Pittsburgh School of Medicine in the United States were included in this study. A comparative analysis was conducted to evaluate the similarities and differences in clinical and laboratory features, damage accrual, and treatment experiences between the two populations.

RESULTS

A total of 174 patients with childhood-onset SLE were included in this study (108 patients from Turkey and 66 patients from the United States). The female-to-male ratio was similar between the two cohorts (∼3:1, p = .73). The median age at diagnosis was 11.67 years (2.19-17.93) in the Turkish cohort and 13.68 years (2.74-17.93) in the U.S. cohort (p < .001). Photosensitivity (45.4% and 21.2%; p = .007) and renal involvement (41.7% and 36.4%; p = .045) were higher in the Turkish cohort. Anti-Ro/SSA (34.8% and 15.7%; p < .001), anti-Sm (59.1% and 19.4%; p < .001), and anti-RNP (47.0% and 14.8%; p < .001) positivity was more frequent in the U.S. cohort. Current use of rituximab (37.9% and 1.9%; p < .001) and belimumab (19.7% and 0%; p < .001) was more prevalent in the U.S. cohort, while the use of cyclophosphamide (often according to the low dose Euro-Lupus protocol) throughout the disease course (24.1% and 4.5%; p < .001) was more frequent in the Turkish cohort. SLICC/ACR Damage Index scores were not different between the two cohorts.

CONCLUSION

This study provides detailed clinical and laboratory features of childhood-onset SLE in two independent and geographically divergent cohorts. Our findings suggest an earlier age of disease onset and a higher prevalence of kidney involvement in Turkish patients. Differences in treatment approaches were also noted. However, damage accrual related to SLE does not appear to be different between the two patient populations.

Long-term outcomes and predictive factors of achieving low disease activity status in childhood systemic lupus erythematosus: a Chinese bicentric retrospective registered study

Background

This study aims to explore the clinical value of low disease activity state (LDAS) in the treat-to-target strategy of pediatric systemic lupus erythematosus (pSLE) and find the risk factors for never reaching LDAS.

Methods

A total of 272 children with SLE who were diagnosed and followed up in two tertiary hospitals in China during the period from January 2012 to December 2019 were involved in this study, and the clinical presentation, pathology, and treatment were retrospectively studied.

Results

The male-to-female ratio was 1:5.2, the age at diagnosis was 11.1 years (IQR, 9.8-13.1 years), the disease duration was 1.0 month (IQR, 0.5-2.0 months), and follow-up was 36.5 months (IQR, 25.7-50.9 months). During follow-up, 230 children achieved LDAS, and 42 were never been in. Male (P = 0.018), mucosal ulcer (P = 0.048), liver function damage (P = 0.026), cardiac effusion (P = 0.034), anemia (P = 0.048), urine red blood cells (P = 0.017), urinary leukocytes (P = 0.032), and endothelial cell proliferation in renal biopsy (P = 0.004)-these indexes have statistical differences between the two groups in the baseline. At baseline, endothelial cell proliferation (P = 0.02) is an independent risk factor for never achieving LDAS by multivariate logistic analysis. During follow-up, non-compliance was a risk factor for never achieving LDAS by comparing between groups. Children with biologics achieved LDAS at a higher rate than children without biologics (P = 0.038). The proportion of organ damage in patients never been in LDAS was significantly higher than that in patients who achieved LDAS (P < 0.001).

Conclusion

Endothelial cell proliferation in renal biopsy and non-compliance during follow-up were independent risk factors for never achieving LDAS. At the end of the follow-up, the organ damage in the remission group was similar to that in the LDAS group, indicating that LDAS can be used as a target for pSLE treatment.

Defining remission in childhood-onset lupus: PReS-endorsed consensus definitions by an international task force

OBJECTIVE

To derive childhood-onset SLE (cSLE) specific remission definitions for future treat-to-target (T2T) trials, observational studies, and clinical practice.

METHODS

The cSLE International T2T Task Force conducted Delphi surveys exploring paediatric perspectives on adult-onset SLE remission targets. A modified nominal group technique was used to discuss, refine, and agree on the cSLE remission target criteria.

RESULTS

The Task Force proposed two definitions of remission: 'cSLE clinical remission on steroids (cCR)' and 'cSLE clinical remission off steroids (cCR-0)'. The common criteria are: (1) Clinical-SLEDAI-2 K = 0; (2) PGA score < 0.5 (0-3 scale); (4) stable antimalarials, immunosuppressive, and biologic therapy (changes due to side-effects, adherence, weight, or when building up to target dose allowed). Criterion (3) in cCR is the prednisolone dose ≤0.1 mg/kg/day (maximum 5 mg/day), whereas in cCR-0 it is zero.

CONCLUSIONS

cSLE definitions of remission have been proposed, maintaining sufficient alignment with the adult-SLE definition to facilitate life-course research.

Treat-to-Target in Pediatric Rheumatic Diseases

PURPOSE OF REVIEW

To summarize the current evidence on the adoption of the treat-to-target (T2T) strategy in pediatric rheumatic diseases (PRD).

RECENT FINDINGS

The recent advances in the management of PRD have markedly increased the ability to achieve disease remission. Complete disease quiescence is regarded as the ideal therapeutic goal because its attainment leads to lesser long-term damage and physical disability, and to optimization of quality of life. Studies in adult rheumatic diseases have shown that patient outcomes are improved if complete suppression of the inflammatory process is aimed for by frequent adjustments of therapy according to quantitative indices. This approach, which underlies the T2T concept, has been applied in strategic trials in rheumatoid arthritis (RA). Furthermore, recommendations for the T2T have been issued for RA and other adult rheumatic diseases. There is currently a growing interest for the introduction of T2T in PRD, and recommendations for treating juvenile idiopathic arthritis (JIA) to target were promulgated. A similar initiative has been undertaken for childhood-onset systemic lupus erythematosus. Preliminary therapeutic studies have explored the T2T design in JIA. The T2T strategy is a modern therapeutic approach that holds the promise of improving the outcomes in patients with PRD.

Usefulness of the lupus low disease activity state as a treatment target in childhood-onset SLE

OBJECTIVE

Treat-to-target (T2T) strategies are advocated to improve prognosis in childhood-onset SLE (cSLE). Proposed T2T states include SLEDAI score of <4 (SLEDAI-LD), limited corticosteroid use (low-CS), and lupus low disease activity state (LLDAS). We sought to compare T2T states for their association with cSLE prognosis under consideration of relevant disease characteristics such as pre-existing damage, race and lupus nephritis (LN).

METHODS

Longitudinal data from 165 patients enrolled in the Cincinnati Lupus Registry were included. LN presence was based on renal biopsy, and patients were followed up until 18 years of age.

RESULTS

The 165 patients (LN: 45, white: 95) entered the registry within a median of 0 (IQR: 0-1) year post diagnosis and were followed up for a median of 4 (IQR: 2-5) years during which 80%, 92% and 94% achieved LLDAS, low-CS and SLEDAI-LD. Patients with LN were significantly less likely to achieve any T2T state (all p<0.03) and required a significantly longer time to reach them (all p<0.0001). Over the study period, patients maintained low-CS, SLEDAI-LD or LLDAS for a median of 76% (IQR: 48%-100%), 86% (IQR: 55%-100%) or 39% (IQR: 13%-64%) of their follow-up. Significant predictors of failure to maintain LLDAS included LN (p≤0.0062), pre-existing damage (p≤0.0271) and non-white race (p≤0.0013). There were 22%, 20% and 13% of patients who reached SLEDAI-LD, CS-low and LLDAS and nonetheless acquired new damage. Patients with LN had a higher risk of new damage than patients without LN even if achieving low-CS (p=0.009) or LLDAS (p=0.04).

CONCLUSIONS

Patients with LN and pre-existing damage are at higher risk of increased future damage acquisition, even if achieving a T2T state such as LLDAS. Among proposed common T2T states, the LLDAS is the hardest to achieve and maintain. The LLDAS may be considered the preferred T2T measure as it conveys the highest protection from acquiring additional disease damage.

PReS-endorsed international childhood lupus T2T task force definition of childhood lupus low disease activity state (cLLDAS)

OBJECTIVE

To achieve a consensus-based definition of Low Disease Activity (LDA) for use in cSLE trials.

METHODS

The International cSLE T2T Task Force, comprising of paediatric rheumatologists/nephrologists, and adult rheumatologists undertook a series of Delphi surveys/consensus meetings to discuss, refine, and vote upon cSLE LDA criteria.

RESULTS

The Task Force agreed that LDA should be based upon the adult-SLE Lupus Low Disease Activity State definition (LLDAS), with modifications to make it applicable to cSLE (cLLDAS). They agreed upon five cLLDAS criteria: (1) SLE Disease Activity Index (SLEDAI)-2 K ≤4, with no activity in major organ systems; (2) no new features of lupus disease activity compared with the last assessment; (3) Physician Global Assessment score of ≤1 (0-3 scale); (4) prednisolone dose of ≤0.15 mg/kg/day, 7.5 mg/day/maximum; while on (5) stable antimalarials, immunosuppressives, and biologics.

CONCLUSIONS

A cSLE-appropriate definition of cLLDAS has been generated, maintaining alignment with the adult-SLE definition to promote life-course research.

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.

Current views on lupus in children

PURPOSE OF REVIEW

This manuscript provides an update on clinical and pathophysiological features of juvenile-onset systemic lupus erythematosis (jSLE), challenges applying adult-derived classification criteria, and recent advances in treatment and care.

RECENT FINDINGS

Significant scientific advances have improved the understanding of genetic factors (both genetic causes and risk alleles) and associated phenotypic features. Panels of urine/blood biomarker candidates aid in diagnosing jSLE, monitoring disease activity and predicting treatment response. Available classification criteria have been extensively assessed, with differences in clinical and immunological phenotypes of patients across age groups and ethnicities affecting their performance in jSLE. Therapeutic options remain limited and are based on protocols for adult-onset SLE patients. International efforts to inform development of a treat-to-target (T2T) approach for jSLE have yielded cohort-level evidence that target attainment reduces the risk of severe flare and new damage, and treatment compliance.

SUMMARY

Recent studies have significantly improved our understanding of jSLE pathogenesis, highlighting important differences between jSLE and adult SLE, and providing the basis of biomarker development and target-directed individualized treatment and care. Future work focused on development of a T2T approach in jSLE is eagerly awaited.

Outcomes of achieving lupus low disease activity state and damage accrual in childhood-onset systemic lupus erythematosus

INTRODUCTION

At present, the treat-to-target approach has been proposed with the lupus low disease activity state (LLDAS) as an achievable target.

OBJECTIVES

To determine damage accrual and baseline clinical characteristics associated with achieving LLDAS within 12 months of treatment in patients with childhood-onset systemic lupus erythematosus (c-SLE).

METHODS

This retrospective cohort study was conducted at the largest university-based tertiary referral center in Thailand. Data of c-SLE patients (≤ 18 years) at diagnosis who were followed ≥ 12 months during January 2009 to December 2019 were collected. SLE disease status was categorized into LLDAS and non-optimally controlled state. SLEDAI-2K score was used to assess disease activity. Damage accrual was assessed by a pediatric version of the SLICC/ACR damage index.

RESULTS

A total of 232 c-SLE patients (85.8% female) were included. At 12 months of treatment, 109 (47%) patients achieved LLDAS. Damage accrual was observed in 93 (40.1%) patients at the mean follow-up time of 6.2 ± 3.7 years. Damage accrual was significantly lower in patients who achieved LLDAS within 12 months than in those non-optimally controlled (p = 0.002). The median time to achieving LLDAS was 12.6 months (95%CI: 11.19-13.97). The median time to achieving LLDAS was significantly shorter in those without renal involvement (10.8 months, 95%CI: 9.62-12.00 vs. 15.6 months, 95%CI: 13.76-17.52, respectively; p = 0.044). Multivariable logistic regression analysis revealed absence of renal involvement as the predictor of achieving LLDAS within 12 months of treatment (aOR: 2.430, 95%CI: 1.420-4.158; p = 0.001).

CONCLUSIONS

Achieving LLDAS within 12 months of treatment was associated with lower damage accrual. Absence of renal involvement was the predictor of achieving LLDAS within 12 months of treatment. Key Points • LLDAS is a promising and achievable treatment target in c-SLE. • Achieving LLDAS within 12 months of treatment is associated with lower damage accrual. • Absence of renal involvement is the predictor of achieving LLDAS within 12 months of treatment.

CD8+ T-Cells in Juvenile-Onset SLE: From Pathogenesis to Comorbidities

Diagnosis of systemic lupus erythematosus (SLE) in childhood [juvenile-onset (J) SLE], results in a more severe disease phenotype including major organ involvement, increased organ damage, cardiovascular disease risk and mortality compared to adult-onset SLE. Investigating early disease course in these younger JSLE patients could allow for timely intervention to improve long-term prognosis. However, precise mechanisms of pathogenesis are yet to be elucidated. Recently, CD8+ T-cells have emerged as a key pathogenic immune subset in JSLE, which are increased in patients compared to healthy individuals and associated with more active disease and organ involvement over time. CD8+ T-cell subsets have also been used to predict disease prognosis in adult-onset SLE, supporting the importance of studying this cell population in SLE across age. Recently, single-cell approaches have allowed for more detailed analysis of immune subsets in JSLE, where type-I IFN-signatures have been identified in CD8+ T-cells expressing high levels of granzyme K. In addition, JSLE patients with an increased cardiometabolic risk have increased CD8+ T-cells with elevated type-I IFN-signaling, activation and apoptotic pathways associated with atherosclerosis. Here we review the current evidence surrounding CD8+ T-cell dysregulation in JSLE and therapeutic strategies that could be used to reduce CD8+ T-cell inflammation to improve disease prognosis.