Kidney Week

Abstract: FR-PO436

Urinary Epidermal Growth Factor (uEGF) and Monocyte Chemoattractant Protein-1 (uMCP1) as Biomarkers of Renal Involvement in ANCA-Associated Vasculitis (AAV)

Session Information

• CKD: Risk Factors for Incidence and Progression - II
  November 03, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Chronic Kidney Disease (Non-Dialysis)

• 301 CKD: Risk Factors for Incidence and Progression

Authors

• Ju, Wenjun, University of Michigan, Ann Arbor, Michigan, United States

Wenjun Ju,

• Najem, Catherine, University of Pennsylvania, Philadelphia, Pennsylvania, United States

Catherine Najem,

• Nair, Viji, University of Michigan, Ann Arbor, Michigan, United States

Viji Nair,

• Cuthbertson, David D, University of South Florida, Tampa, Florida, United States

David D Cuthbertson,

• Rhee, Rennie L, University of Pennsylvania, Philadelphia, Pennsylvania, United States

Rennie L Rhee,

• Mariani, Laura H., University of Michigan, Ann Arbor, Michigan, United States

Laura H. Mariani,

• Krischer, Jeffrey P., University of South Florida, Tampa, Florida, United States

Jeffrey P. Krischer,

• Kretzler, Matthias, University of Michigan, Ann Arbor, Michigan, United States

Matthias Kretzler,

• Merkel, Peter A., University of Pennsylvania, Philadelphia, Pennsylvania, United States

Peter A. Merkel,

Group or Team Name

• Vasculitis Clinical Research Consortium and NEPTUNE Network

Background

EGF mediates distal tubular epithelial cell function and regeneration. MCP-1 recruits leukocytes to areas of inflammation. This study examined the utility of uEGF and uMCP-1 as biomarkers of renal disease in AAV.

Methods

uEGF and uMCP-1 (normalized to urine creatinine) were measured at enrollment, an active renal disease visit (index), 1-2 visits prior to and after the index, and at 1 year follow-up utilizing urine samples from a multicenter longitudinal cohort of patients with AAV. Chronic kidney disease (CKD) was defined as eGFR< 60 mL/min/1.73 m2 for >3 months. Index visit was defined as the first visit with a new/worse BVAS/WG renal item since prior visit. To assess the association of each biomarker with disease activity, a mixed effect model was used, adjusting for ANCA type (MPO or PR-3), urinary albumin/creatinine ratio (ACR), eGFR, visit type. To assess time to CKD, a Cox proportional hazard model was used, adjusting for demographics, ANCA type, ACR, and eGFR.

Results

At baseline, 165/544 patients had CKD. After adjusting for sex, age, race, ANCA type, eGFR, and albumin/Cr, for each unit increase in baseline uEGF/Cr there was a lower risk of CKD [HR=0.62, (0.43, 0.88), p=0.01)]. Higher baseline uMCP-1/Cr didn’t predict risk of CKD [HR=1.14, (0.88, 1.48), p=0.33)]. 112 patients had active renal disease. uEGF/Cr levels did not significantly differ between pre-, post-, and index visits. Compared to index visit, uMCP-1/Cr was lower at pre- and post-index visits (p=0.04 and p<0.01).

Conclusion

In AAV, uEGF predicts progression to CKD independently of ACR and eGFR. uMCP-1, but not uEGF, correlates with renal disease activity. uEGF and uMCP-1 are useful biomarkers in AAV.

Funding

• NIDDK Support