Background: A considerable diversity of prognosis is seen with idiopathic membranous nephropathy (IMN). The initial factors affecting long-term outcome remain unclear.
Methods: We studied retrospectively 30 patients with IMN who had been followed up for at least 5 years, or until end-stage renal failure (ESRF). We analyzed the prognostic factors of ESRF in the first renal biopsies; these factors included presence of tubulointerstitial lesions and foam cells, as well as expression of CD68, monocyte chemoattractant protein-1 (MCP-1), its cognate receptor chemokine receptor 2 (CCR2) and alpha-smooth muscle actin.
Results: The patients who developed ESRF showed higher percentages of glomerular segmental sclerosis, interstitial MCP-1 expression, CCR2- or CD68-positive monocyte/macrophages and foam cells in the interstitium, and these proved on multivariate analysis to be independent risk factors for ESRF. Finally, ESRF was characterized by the presence of ten interstitial CD68-positive cells per visual field at 200x magnification (hazard ratio 4.096, CI 1.271-15.029, p < 0.001).
Conclusions: Our results suggested that an interstitial infiltration of CD68-positive cells accompanied by MCP-1/CCR2 expression is the most significant indicator of ESRF in IMN.
Copyright 2004 S. Karger AG, Basel