Session Information
Date: Tuesday, November 15, 2016
Title: Systemic Lupus Erythematosus – Clinical Aspects and Treatment - Poster III: Biomarkers and Nephritis
Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose: B cell Activating Factor of the TNF Family (BAFF) and A Proliferation Inducing Ligand (APRIL) help B cell activation, maintenance and plasma cell survival. Consequently, these facilitate production of pathogenic autoantibodies in SLE and lupus nephritis. B cells infiltration has been demonstrated in kidneys of patients with Lupus Nephritis (LN). Serum levels of BAFF and APRIL have shown inconsistent relationships with lupus disease activity. We evaluated urinary levels of BAFF and APRIL as a biomarker for LN.
Methods: Thirty-six patients with proliferative lupus nephritis (AN), 10 with active lupus without nephritis (AL) and 15 healthy controls (HC) were studied. APRIL and BAFF levels were measured in both serum and urine using ELISA. Urine levels were normalized to urinary creatinine excretion. Urine levels were correlated with conventional disease activity markers like SLEDAI, renal SLEDAI, and proteinuria. Levels were reassessed in 20 AN patients at 6 months, after treatment with cyclophosphamide.
Results: At baseline, urinary APRIL (uAPRIL) and BAFF (uBAFF) were significantly raised in AN patients as compared to controls. [Table1] uAPRIL but not uBAFF had correlation with renal SLEDAI in patients with AN. (r= 0.36, p<0.05). On ROC analysis, uBAFF (AUC 0.825) and uAPRIL (AUC 0.781)performed better than low C3, C4 and raised anti-dsDNA antibodies in differentiating AN and AL patients. The uBAFF and uAPRIL levels did not correlate with their serum levels suggesting in situ generation in the kidneys. On follow up uAPRIL levels reduced (125 pg/mg to 36 pg/mg, p<0.05). However uBAFF levels reduced only in 16 responders (158 to 67 pg/mg, p<0.05). Two of the 4 non-responders had increase in uBAFF levels.
Conclusion: uBAFF and uAPRIL are potential biomarkers of proliferative lupus nephritis. Table 1: Disease activity and BAFF, APRIL levels at baseline.
| Parameter | Lupus nephritis (n=36) | Active non-renal lupus (n=10) | Lupus, non nephritis |
| Age in years (median, range) | 32 (19 – 59) | 27 (23 – 36) | 31 (19-50) |
| SLEDAI 2K (median, range) | 18 (8-30) | 9 (6-20) | NA |
| Renal SLEDAI (median, range) | 8 (4-16) | 0 | NA |
| Urine 24 hour protein- g/24 hours | 4.9 (3.6) | 0.31 (0.13)* | NA |
| Normalized Urine BAFF (pg/mg) |
240 (290) |
60.9 (62)* |
58 (101)* |
| Normalized Urine APRIL (pg/mg) |
125 (116) |
28.4 (20)*# |
01 (05)* |
| Serum BAFF (ng/ml) |
0.184 (0.26) |
0.27 (0.20) |
0.135(0.69) |
| Serum APRIL (ng/ml) |
1.249 (0.72) |
1.38 (0.53) |
2.00 (1.74) |
| *p <0.05 compared to lupus nephritis, # p<0.05 compared to healthy control All values: mean with standard deviation NA: not applicable
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To cite this abstract in AMA style:
Phatak S, Chaurasia S, Mishra S, Gupta R, Aggarwal A, Misra R. Urinary BAFF and APRIL Levels: Potential Biomarkers of Active Lupus Nephritis [abstract]. Arthritis Rheumatol. 2016; 68 (suppl 10). https://acrabstracts.org/abstract/urinary-baff-and-april-levels-potential-biomarkers-of-active-lupus-nephritis/. Accessed .« Back to 2016 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/urinary-baff-and-april-levels-potential-biomarkers-of-active-lupus-nephritis/