Clinical measurement of lupus nephritis activity is inferior to biomarker-based activity assessment using the renal activity index for lupus nephritis in childhood-onset systemic lupus erythematosus.

OBJECTIVES: The renal activity index for lupus (RAIL) measures lupus nephritis (LN) activity considering urine levels of 6 biomarkers (neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, kidney injury molecule-1, adiponectin, haemopexin, ceruloplasmin). We aimed to compare the accuracy of the RAIL and the renal domain-score of the SLE disease activity index (rSLEDAI) in detecting LN activity. METHODS: Random urine samples of patients with childhood-onset SLE with and without LN were assayed and scores of the RAIL, and RAIL standardised for urine creatinine (RAIL-Cr) were calculated. Clinical LN activity was measured by the rSLEDAI, and histological activity of LN was categorised as inactive/low-moderate/high for National Institute of Health-activity index scores of <2/2-10/>10, respectively. RESULTS: 115 patients were included in the analysis (47 patients without and 68 with LN). RAIL, RAIL-Cr and rSLEDAI scores at the time (±3 months) of kidney biopsy were available for 32 patients. Median rSLEDAI, RAIL and RAIL-Cr values were 4, -0.04, 0.02 for inactive LN, 12, 0.7 and 0.9 for low-moderate LN activity and 12, 2 and 1.8 for high LN activity, respectively. The area under the receiver operating characteristic curve (AUC) to capture high LN activity was the lowest for the rSLEDAI (AUC=0.62), followed by the RAIL-Cr (AUC=0.73) and RAIL (AUC=0.79). Notably, when testing urine samples collected during routine clinic visits remote (>3 months) from a kidney biopsy, 50% patients with rSLEDAI scores of 0 had RAIL scores reflecting low-moderate LN activity. CONCLUSION: Monitoring of renal inflammation in children and adolescents with SLE can be improved by the measurement of urine biomarkers. The RAIL may constitute important auxiliary tool for the surveillance of LN in a clinical setting and assist with the decision to obtain a kidney biopsy.

Performance of the New 2019 European League Against Rheumatism/American College of Rheumatology Classification Criteria for Systemic Lupus Erythematosus in Children and Young Adults.

OBJECTIVE: To compare the diagnostic usefulness of the 2019 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) classification criteria for systemic lupus erythematosus (SLE) to that of the 1997 ACR classification criteria for SLE when applied to youths (age ≤21 years) with SLE. METHODS: Data were extracted from electronic health records of patients followed at a large academic pediatric hospital. The treating rheumatologist's diagnosis of SLE served as the standard criterion for identifying SLE patients (cases). Controls were patients with juvenile dermatomyositis (DM), juvenile scleroderma, or juvenile systemic sclerosis (SSc). The 2019 EULAR/ACR criteria and the 1997 ACR criteria were tested against the standard criterion. RESULTS: A total of 112 SLE patients ages 2-21 years and 105 controls ages 1-19 years (66% juvenile DM, 34% juvenile scleroderma or juvenile SSc) were available for analysis. The 2019 EULAR/ACR criteria had significantly higher sensitivity (85% versus 72%; P = 0.023) and similar specificity (83% versus 87%; P = 0.456) than the 1997 ACR criteria. The mean ± SD 2019 EULAR/ACR classification summary scores were significantly higher among non-White than White patients (22.41 ± 10.04 versus 17.59 ± 9.19; P < 0.01). The sensitivity of the 2019 EULAR/ACR criteria in non-White/White patients was 92%/80% (P = 0.08) versus 83%/64% (P < 0.02) for the 1997 ACR criteria. The sensitivity of the 2019 EULAR/ACR criteria was not affected by age or sex. CONCLUSION: The 2019 EULAR/ACR criteria efficiently classify youths with SLE, irrespective of age, sex, and race. Compared to the 1997 ACR criteria, the new criteria are significantly more sensitive and similarly specific in youths with SLE.

Meta-analysis of Genetic Modifiers Reveals Candidate Dysregulated Pathways in Amyotrophic Lateral Sclerosis.

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease that has significant overlap with frontotemporal dementia (FTD). Mutations in specific genes have been identified that can cause and/or predispose patients to ALS. However, the clinical variability seen in ALS patients suggests that additional genes impact pathology, susceptibility, severity, and/or progression of the disease. To identify molecular pathways involved in ALS, we undertook a meta-analysis of published genetic modifiers both in patients and in model organisms, and undertook bioinformatic pathway analysis. From 72 published studies, we generated a list of 946 genes whose perturbation (1) impacted ALS in patient populations, (2) altered defects in laboratory models, or (3) modified defects caused by ALS gene ortholog loss of function. Herein, these are all called modifier genes. We found 727 modifier genes that encode proteins with human orthologs. Of these, 43 modifier genes were identified as modifiers of more than one ALS gene/model, consistent with the hypothesis that shared genes and pathways may underlie ALS. Further, we used a gene ontology-based bioinformatic analysis to identify pathways and associated genes that may be important in ALS. To our knowledge this is the first comprehensive survey of ALS modifier genes. This work suggests that shared molecular mechanisms may underlie pathology caused by different ALS disease genes. Surprisingly, few ALS modifier genes have been tested in more than one disease model. Understanding genes that modify ALS-associated defects will help to elucidate the molecular pathways that underlie ALS and provide additional targets for therapeutic intervention.