CD68 POSITIVE CELLS IN RENAL BIOPSY PREDICT LONG TERM PROGNOSIS IN PROLIFERATIVE LUPUS NEPHRITIS

Abstract

Introduction and Aims:Studies in proliferative lupus nephritis (LN) showed that in more severe clinical forms the renal histology showed increase macrophages detected by immunohistochemistry. However no long-term assessment of this data is known. The aim of this study was to describe any relations of renal outcomes with tecidual macrophages (CD68+) expressed in renal biopsy specimens obtained on the diagnosis. Methods:Forty six newly diagnosed patients with proliferative LN were prospectively followed-up during 3.5 (3.2 - 4.0) years. Conventional laboratory tests were collected on diagnosis and on last follow-up. Renal biopsy was done on diagnosis and immunohistochemical study was performed with monoclonal antibody anti-CD68 (DAKO) and macrophages MCP-1 (R&D), and results expressed as cells/microscopic fields. Patients were stratified in two groups according to renal outcome: GFR ≤ 60 mL/min/1.73m2at the end of follow-up (n=24) and GFR > 60mL/min/1.73m2(n=22). Considering treatment, all patients received prednisone and 6 pulses of cyclophosphamide (CYA) on induction. Maintenance treatment was conventional and applied in both groups. Results: Considering all patients (n=46) tubule and interstitial CD68+cells showed negative correlation with final MDRD (r= - 0.3, p=0.01 and r= -0.45, p=0.001). Macrophages MCP-1 interstitial had positive correlation with chronicity index (r=0.4, p=0.0031). Conclusions:Tubule and interstitial CD68+cells expression on renal biopsies may predict long term GFR in proliferative lupus nephritis.