Abstract: SA-PO111

Urine VCAM-1 and ICAM-1 as Biomarkers for Active and Chronic Kidney Injury in Lupus Nephritis

Session Information

Category: Glomerular

  • 1005 Clinical Glomerular Disorders

Authors

  • Wadhwani, Shikha, The Ohio State University, Columbus, Ohio, United States
  • Zhang, Xiaolan, The Ohio State University, Columbus, Ohio, United States
  • Mejia-Vilet, Juan M., Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico, Mexico
  • Alvarado, Anthony S, The Ohio State University, Columbus, Ohio, United States
  • Nadasdy, Tibor, The Ohio State University, Columbus, Ohio, United States
  • Rovin, Brad H., The Ohio State University, Columbus, Ohio, United States
Background

Urine levels of the adhesion molecules VCAM-1 and ICAM-1 may reflect active kidney disease in patients with lupus nephritis (LN), but it is unknown if these analytes are biomarkers of kidney pathology. This study investigated the relationship of urine (u)VCAM-1 and uICAM-1 to renal histology in LN.

Methods

uVCAM-1 and uICAM-1 were measured by ELISA at the time of kidney biopsy in 129 LN patients. SLE patients without kidney involvement (non-renal (nr)SLE, n=35) served as controls. Urine analyte levels were normalized to urine creatinine concentration, log-transformed and then examined in relation to ISN/RPS histologic class and specific histologic lesions using ANOVA, nonparametric Wilcoxon ranked-sum testing and linear regression as appropriate.

Results

uVCAM (R=0.57; p<0.0001) and uICAM (R=0.52; p<0.0001) correlated with proteinuria. Mean uVCAM and uICAM levels from LN patients were 5.4 and 2.2-fold higher, respectively than levels from nrSLE (p<0.0001). Significance was maintained when classes II-V LN were compared individually to nrSLE. In proliferative LN, uVCAM and uICAM levels positively correlated with biopsy activity index (R=0.32; p= 0.0037 and R=0.26; p=0.0143 respectively). uVCAM and uICAM levels were elevated in patients whose biopsies had karyorrhexis/fibrinoid necrosis (p<0.006; p<0.02, uVCAM; uICAM), hyaline deposits (p<0.006; p<0.02, uVCAM; uICAM) and PMN infiltrates (p < 0.003; p<0.03, uVCAM; uICAM). Only uVCAM was elevated in the presence of cellular crescents (p=0.002), and neither analyte reflected interstitial inflammation. Conversely, uICAM was negatively associated with biopsy chronicity index (R=0.32; p=0.0026), and was significantly lower in patients whose biopsies showed glomerular sclerosis and fibrous crescents (p=0.03; p=0.002). uICAM did not reflect interstitial fibrosis or tubular atrophy.

Conclusion

uVCAM-1 and uICAM-1 are biomarkers for glomerular injury in LN. uVCAM-1 levels reflect glomerular inflammation while uICAM-1 levels indicate chronic glomerular damage.

Funding

  • NIDDK Support