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.

International Consensus for the Dosing of Corticosteroids in Childhood-Onset Systemic Lupus Erythematosus With Proliferative Lupus Nephritis.

OBJECTIVE: To develop a standardized steroid dosing regimen (SSR) for physicians treating childhood-onset systemic lupus erythematosus (SLE) complicated by lupus nephritis (LN), using consensus formation methodology. METHODS: Parameters influencing corticosteroid (CS) dosing were identified (step 1). Data from children with proliferative LN were used to generate patient profiles (step 2). Physicians rated changes in renal and extrarenal childhood-onset SLE activity between 2 consecutive visits and proposed CS dosing (step 3). The SSR was developed using patient profile ratings (step 4), with refinements achieved in a physician focus group (step 5). A second type of patient profile describing the course of childhood-onset SLE for ≥4 months since kidney biopsy was rated to validate the SSR-recommended oral and intravenous (IV) CS dosages (step 6). Patient profile adjudication was based on majority ratings for both renal and extrarenal disease courses, and consensus level was set at 80%. RESULTS: Degree of proteinuria, estimated glomerular filtration rate, changes in renal and extrarenal disease activity, and time since kidney biopsy influenced CS dosing (steps 1 and 2). Considering these parameters in 5,056 patient profile ratings from 103 raters, and renal and extrarenal course definitions, CS dosing rules of the SSR were developed (steps 3-5). Validation of the SSR for up to 6 months post-kidney biopsy was achieved with 1,838 patient profile ratings from 60 raters who achieved consensus for oral and IV CS dosage in accordance with the SSR (step 6). CONCLUSION: The SSR represents an international consensus on CS dosing for use in patients with childhood-onset SLE and proliferative LN. The SSR is anticipated to be used for clinical care and to standardize CS dosage during clinical trials.

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.

Dietary mercury exposure to endangered California Clapper Rails in San Francisco Bay.

California Clapper Rails (Rallus longirostris obsoletus) are an endangered waterbird that forage in tidal-marsh habitats that pose risks from mercury exposure. We analyzed total mercury (Hg) in six macro-invertebrate and one fish species representing Clapper Rail diets from four tidal-marshes in San Francisco Bay, California. Mercury concentrations among individual taxa ranged from lowest at Colma Creek (mean range: 0.09-0.2 µg/g dw) to highest at Cogswell (0.2-0.7), Laumeister (0.2-0.9) and Arrowhead Marshes (0.3-1.9). These spatial patterns for Hg matched patterns reported previously in Clapper Rail blood from the same four marshes. Over 25% of eastern mudsnails (Ilyanassa obsolete) and staghorn sculpin (Leptocottus armatus) exceeded dietary Hg concentrations (ww) often associated with avian reproductive impairment. Our results indicate that Hg concentrations vary considerably among tidal-marshes and diet taxa, and Hg concentrations of prey may provide an appropriate proxy for relative exposure risk for Clapper Rails.