PReS-FINAL-2299: Novel biomarkers for the assessment of pediatric systemic lupus erythematosus nephritis (preliminary report)

Methods Twenty-four patients (16 female) with pSLE nephritis (44 serum samples, 22 in active nephritis) and 21 patients (18 female) with pSLE without nephritis (32 serum samples, 19 in active pSLE) were enrolled in the study. The disease control group included 17 patients with nephritis of other causality (Henoch-Schönlein purpura nephritis, IgA nephropathy, postinfectious glomerulonephritis, membranous glomerulonephritis), who provided equal serum samples. The SLICC renal activity score was applied for assessing pSLE nephritis disease activity and ECLAM for global pSLE disease activity. The biomarkers’ levels were determined by ELISA. Results The pSLE nephritis patients had significantly higher serum levels of anti-NCS [median: 48.89 (IQR: 31.4880.81) U/ml versus 12.5 (11.5-27.8) U/ml, p < 0.001], anti-C1q [22.75 (12.77-56.4) U/ml versus 12.5 (12.512.5) U/ml, p < 0.001], anti-GBM [3.88 (2.25-6.94) U/ml versus 2.2 (2.2-2.4) U/ml, p = 0.002] and HMGB1 [9.9 (5.7-32.23) ng/ml versus 2.5 (2.5-2.5) ng/ml, p < 0,001], than the patients with nephritis of other causality. Serum anti-GBM levels were significantly higher in the pSLE nephritis patients compared to the pSLE patients without nephritis [3.88 (2.25-6.94) U/ml versus 2.25 (2.2-2.83) U/ml, p = 0.014], while this was not true for the rest of the biomarkers. In the pSLE nephritis patients no correlation was found between serum antiGBM levels and pSLE nephritis disease activity. Serum anti-NCS and anti-C1q levels were positively correlated with the ECLAM score in the pSLE patients as a whole (p = 0.002, rho = 0.492 and p = 0.007, rho = 0.461, respectively).