Urinary vascular cell adhesion molecule, but not neutrophil gelatinase-associated lipocalin, is associated with lupus nephritis

Objective. Vascular cell adhesion molecule-1 (VCAM-1), an adhesion molecule, is involved in the progression of glomerular and tubulointerstitial injury. Neutrophil gelatinase-associated lipocalin (NGAL), a member of the lipocalin superfamily, has been shown to rise in both acute and chronic kidney damage. Both VCAM-1 and NGAL have been found at high levels in the urine of patients with active lupus nephritis. We investigated both as potential biomarkers for lupus nephritis. Methods. VCAM-1 and NGAL were measured by ELISA during 1 to 8 clinic visits in 107 patients with systemic lupus erythematosus (SLE; 91% women, 51% black, 36% white, 4% Asian, 4% Hispanic, and 5% others) for a total of 190 visits. Patients' mean age was 41 years. We analyzed the relationship between these potential urine biomarkers and the urine protein/creatinine ratio (urine Pr/Cr), the Systemic Lupus International Collaborating Clinics (SLICC) renal activity score, SLE Disease Activity Index renal descriptors, and other clinical variables. Results. VCAM-1 levels were strongly associated with the physician's global estimate of disease activity (p = 0.0002), the renal visual analog scale (p < 0.0001), the urine Pr/Cr (p < 0.0001), and SLICC renal activity score (p < 0.0001). VCAM-1 levels were also associated with a urine Pr/Cr ≥ 0.5 (p < 0.0001). NGAL was not associated with any measure of disease activity or with lupus serologies. Conclusion. Urine VCAM-1 had a strong association with measures of disease activity, including multiple renal activity descriptors. In contrast to previous SLE studies, NGAL failed to show any association with lupus nephritis. The Journal of Rheumatology