Performance of the 2019 EULAR/ACR systemic lupus erythematosus classification criteria in a cohort of patients with biopsy-confirmed lupus nephritis

Management of systemic lupus erythematosus: A new scenario

The introduction of targeted biological agents in systemic lupus erythematosus (SLE) has created a momentum for improving overall disease management and patients' prognosis. To achieve this, a comprehensive strategy is required spanning the entire patient journey from diagnosis to prevention and management of late complications and comorbidities. In this review, we focus on four aspects that are closely linked to SLE prognosis, namely early disease recognition and treatment initiation, reduction of the cumulative glucocorticoid exposure, attainment of well-defined targets of remission and low disease activity, prevention of flares and, kidney-protective strategies with non-immune-directed agents. We review the recent literature related to these topics in conjunction with the existing treatment recommendations, highlighting areas of uncertainty and providing guidance towards facilitating the care of SLE patients.

The value of 2019 EULAR/ACR classification criteria in predicting lupus nephritis in childhood-onset systemic lupus erythematosus

BACKGROUND

We investigated the role of European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) classification criteria for the prediction of LN among children with SLE.

METHODS

The data of the patients with childhood-onset SLE diagnosed based on 2012 Systemic Lupus International Collaborating Clinics (SLICC) criteria were retrospectively evaluated. Based on 2019 EULAR/ACR classification criteria, the scoring was done at the time of renal biopsy.

RESULTS

Fifty-two patients (12 with LN, 40 without LN) were included. The mean score was higher in patients with LN than those without (30.8±6.14, 19.8±7.76, respectively, p=0.000). The score value had indicative value for LN (area under curve [AUC]:0.863±0.055, cut-off value:22.5, p=0.000). Lymphocyte counts had a predictive value for LN (cut-off value:905/mm3, AUC:0.688±0.087, p=0.042). The score was positively associated with SLE disease activity index (SLEDAI) and activity index (r=0.879, p=0.000; r=0.811, p=0.001, respectively). There were significant negative associations between score value and GFR (r=-0.582, p=0.047). The patients with renal flare had higher the mean score than those of without renal flare (35±2/25.4±5.57, respectively, p=0.019).

CONCLUSIONS

The EULAR/ACR criteria score could reflect the activity of disease and severity of nephritis in childhood-onset SLE. A point of 22.5 as score value might be an indicator for LN. During scoring, it should be taken into account that lymphopenia might guide the prediction of LN.

Comparison of Urinary Protein/Creatinine Ratio as an Alternative to 24-h Proteinuria in Lupus Nephritis: TUNARI Study

BACKGROUND

Lupus nephritis (LN) occurs in approximately 50% of people with systemic lupus erythematosus (SLE). The 24-h proteinuria (gold standard) is measured among other tests for the control and monitoring of LN activity. This study investigates the use of the protein/creatinine ratio (PCR) as an alternative for the detection of proteinuria and its accuracy compared to the gold standard in a predominantly non-white population.

METHODS

This was a prospective study conducted in Salvador, Brazil, between December 2021 and May 2022. We invited adult patients diagnosed with SLE and LN, regardless of their disease activity. The estimation of the PCR and 24-h proteinuria was performed using conventional methods. The analysis used was Spearman's r correlation coefficient (rs), coefficient of determination (r2), and concordance by the Bland-Altman method. A specific sensitivity was measured by the ROC curve with its respective cut-off by the Youden Index.

RESULTS

We compared 112 samples of 75 patients with LN, with a mean age of 34.5 ± 11.8 years. Of these patients, 85% were women, 87.9% were non-white. A high degree of correlation was observed between PCR with 24-h proteinuria (rs = 0.77 and r2 = 0.59). The ROC analysis shows an area under the curve of 0.92 and the cut-off point calculated by the Youden Index was 0.78 with a sensitivity of 90.0% and specificity of 82%. However, the Bland-Altman graph indicated decreasing concordance as the degree of proteinuria increased, despite showing concordance at high levels of proteinuria.

CONCLUSION

The PCR shows high sensitivity to follow-up patients with LN when compared with 24-h proteinuria. Our findings suggest that PCR is a useful parameter for the evaluating and monitoring patients in complete remission. However, in cases of partial remission, the utility of PCR is limited.

Utility of the 2018 revised ISN/RPS thresholds for glomerular crescents in childhood-onset lupus nephritis: a Pediatric Nephrology Research Consortium study

BACKGROUND

The revised 2018 ISN/RPS Classification System for lupus nephritis (LN) includes calculations for both activity index (A.I.) and chronicity index (C.I.). Unchanged were the thresholds of < 25%, 25-50%, and > 50% crescents to distinguish between mild, moderate, and severe activity/chronicity. We aimed to evaluate these thresholds for percent crescents in childhood-onset LN.

METHODS

Eighty-six subjects < 21 years of age were enrolled from the Pediatric Glomerulonephritis with Crescents Registry, a retrospective multi-center cohort sponsored by the Pediatric Nephrology Research Consortium. Thresholds of 10%, 25%, and 50% for both cellular/fibrocellular and fibrous crescents were interrogated for primary outcomes of kidney failure, eGFR, and eGFR slope.

RESULTS

Median age at time of initial biopsy was 14 years (range 1-21). Median follow-up time was 3 years (range 1-11). Cumulative incidence of kidney failure was 6% at 1 year and 10% at latest follow-up. Median eGFR slope was - 18 mL/1.73 m²/min (IQR - 51 to + 8) at 1 year and - 3 mL/min/1.73 m²/year (IQR - 19 to + 6) at latest follow-up. We found no difference in kidney failure at the proposed < 25% and 25-50% cellular crescents thresholds, and thus added a new provisional threshold of 10% that better predicted outcomes in children. Moreover, use of 10% and 25% thresholds for fibrous crescents showed a fourfold and sevenfold increase in risk of kidney failure.

CONCLUSIONS

In children with crescentic LN, use of 10% and 25% thresholds for cellular crescents better reflects disease activity, while these thresholds for fibrous crescents better discriminates kidney disease outcomes. A higher resolution version of the Graphical abstract is available as Supplementary information.

Diagnostic accuracy of the European League against rheumatism/American College of Rheumatology-2019 versus the Systemic Lupus International Collaborating Clinics-2012 versus the ACR-1997 classification criteria in adult systemic lupus erythematosus: A systematic review and meta-analysis

Aim

To evaluate the diagnostic performance of the American College of Rheumatology (ACR)-1997, the Systemic Lupus International Collaborating Clinics (SLICC)-2012, and the European League against Rheumatism (EULAR)/ACR-2019 classification criteria in adult patients with systemic lupus erythematosus (SLE).

Methods

PubMed, Embase, Web of Science and Cochrane Library databases were searched for literature comparing the three classification criteria of ACR-1997, SLICC-2012 and EULAR/ACR-2019, which took clinical diagnosis as reference. Meta-analysis was used to evaluate and compare the sensitivity, specificity and diagnostic odds ratio of ACR-1997, SLICC-2012 and EULAR/ACR-2019. To assess the early diagnosis capability of the classification criteria, subgroups of patients with disease duration < 3 years and < 1 year were selected for comparison of sensitivity and specificity based on the inclusion of the original study. The sensitivity and specificity of each item in three sets of classification criteria were evaluated. In addition, the clinical and immunological characteristics of patients who did not meet the three classification criteria were compared.

Results

Nine original studies were included in the analysis, including 6404 SLE patients and 3996 controls. Results showed that the diagnostic odds ratios (95% confidence interval) of the SLICC-2012 [136.35 (114.94, 161.75)] and EULAR/ACR-2019 [187.47 (158.00, 222.42)] were higher than those of the ACR-1997 [67.53 (58.75, 77.63)]. Compared with ACR-1997[(0.86 (0.82, 0.89)], SLICC-2012[(0.96 (0.93, 0.97)] and EULAR/ACR-2019[(0.95 (0.92, 0.97)] had higher sensitivity. The specificity of the three classification criteria was similar: ACR-1997, SLICC-2012, and EULAR/ACR-2019 were 0.93 (0.89, 0.95), 0.86 (0.79, 0.91), and 0.91 (0.85, 0.95), respectively. The sensitivity of SLICC-2012 and EULAR/ACR-2019 were higher than that of ACR-1997 in early-course subgroups. Patients who did not meet ACR-1997 had more hypocomplementemia, patients who did not meet SLICC-2012 had more cutaneous lupus and photosensitivity, and patients who did not meet EULAR/ACR-2019 had more cutaneous lupus and leucopenia.

Conclusions

SLICC-2012 and EULAR/ACR-2019 have better diagnostic ability than the ACR-1997, and the sensitivity of the former two criteria is also higher than that of the latter; Moreover, the SLICC-2012 and EULAR/ACR-2019 for patients in the early stages of disease performed equally excellent.

Validation of the 2019 EULAR/ACR classification criteria for systemic lupus erythematosus in ANA-positive Chinese patients

Background:

The aim of this study was to validate the 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria for systemic lupus erythematosus (SLE) in antinuclear antibody (ANA)-positive Chinese patients.

Methods:

Medical records of all adult patients who attended the rheumatology out-patient clinics between May and September 2019 were reviewed. Patients with ever ANA positive (titre ⩾1:80) were included and evaluated for the fulfilment of the 2019 EULAR/ACR, 2012 Systemic Lupus International Collaborating Clinics (SLICC) and 1997 ACR criteria for SLE classification. The performance of these criteria in predicting a clinical diagnosis of SLE as judged by an independent panel of rheumatologists was studied and compared in different subgroups.

Results:

A total of 1533 patients (88.2% women; age at first clinic attendance 45.5 ± 15.6 years) were studied and 562 patients were judged to be clinical SLE. The sensitivity and specificity of the EULAR/ACR (⩾10 points), SLICC and ACR criteria for a clinical diagnosis of SLE was 96.1%, 97.9% and 86.1%; and 85.8%, 86.3% and 94.3%, respectively. Applying the attribution rule to the non-SLE controls, the specificity of the three criteria increased to 95.0%, 92.5% and 98.8%, respectively. The specificity of the EULAR/ACR criteria was higher in male patients (97.9%), those aged >50 years (97.0%) and disease duration of ⩽3 years (97.6%). Using a cut-off of 12 points, the specificity of the EULAR/ACR criteria was further increased (96.6%) while a high sensitivity (95.0%) was maintained.

Conclusion:

In Chinese patients with a positive ANA, the EULAR/ACR criteria for clinical SLE perform equally well to the SLICC criteria. Both the EULAR/ACR and SLICC are more sensitive but less specific than the ACR criteria. The specificity of all the three criteria is enhanced by applying the attribution rule to controls. The specificity of the EULAR/ACR criteria is higher in certain patient subgroups or when the cut-off score is raised.

Clinical characteristics and long-term outcomes in patients with mixed Class III/IV + V and pure proliferative lupus nephritis: A single-center experience

OBJECTIVES

Proliferative lupus nephritis (LN) is a crucial complication in systemic lupus erythematosus (SLE). This study evaluated the clinical implications of coexistence of membranous LN in proliferative LN in terms of clinical characteristics and long-term outcome.

METHODS

We retrospectively reviewed the medical records of patients with SLE who underwent renal biopsy between 2005 and 2018. Patients with proliferative LN based on the 2003 International Society of Nephrology/Renal Pathology Society classification were subclassified into pure (Class III or IV only) and mixed (Class III or IV + Class V) proliferative LN. The clinical features at the time of renal biopsy, incidence of end-stage renal disease (ESRD), and all-cause mortality were compared between patients with mixed or pure proliferative LN.

RESULTS

Of the 171 patients, 30 and 141 were classified into mixed and pure proliferative LN groups, respectively. Patients with pure proliferative LN showed higher anti-dsDNA antibody and lower hemoglobin, platelet, and complement 3 levels than patients with mixed proliferative LN. The SLE disease activity index was also higher in patients with pure proliferative LN (p = 0.047). The pure proliferative LN group showed a higher proportion of Class IV and higher histologic activity index scores (p < 0.001 and p = 0.004, respectively). During the follow-up period of 58.3 months, 18 patients developed ESRD and 15 patients died. ESRD was exclusively observed in patients with pure proliferative LN, although the incidence of ESRD was not statistically different (p = 0.055). All-cause mortality was comparable between the two groups.

CONCLUSION

Pure proliferative LN was associated with higher clinical and histological activities and modestly increased risk of ESRD. Active immunosuppressive treatment would be required to control the renal inflammation in patients with proliferative LN, regardless of the coexistence of membranous LN.