LIGHT, IMMUNOFLUORESCENCE AND ELECTRON MICROSCOPY RENAL BIOPSY FINDINGS AS PREDICTORS OF MORTALITY IN EIGHTY-FIVE SPANISH PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

This study aimed to define prognostic indicators of death inrenal biopsies from Spanish patients with SLE. Renal biopsiesof eighty-five lupus patients with and without clinical nephritis,taken betweeen 1974 and 1987, were reviewed. Samples previouslyprocessed for light (LM), immunofluorescence (IM) and electron(EM) microscopy were analysed blind. Kaplan-Maier curves, log-ranktest, and multivariate Cox's regression statistical methodswere used for comparison of biopsy data in relation to patientsurvival. Univariate analysis showed that vascular hyalinosis,glomerular sclerosis, fibrous crescent and chronicity indexhigher than 3 by LM, and intramembranous dense-deposits by EMare predictors of poor survival. A multivariate approach confirmedthe independent influence of vascular hyalinosis, chronicityindex higher than 3 and intramembranous deposits. A predictivemodel can be constructed with three LM (hyalinosis, tubularatrophy and glomerular sclerosis) and three EM variables (subepithelial,mesangial and intramembranous deposits). Selected renal biopsychanges detected by LM and EM are therefore predictors of deathin patients with lupus. Chronicity markers, more than thoseof activity or severity, are the best prognostic indicators. KEY WORDS: Lupus nephritis, Predictors of mortality in SLE, Survival in lupus nephritis, Electron microscopy, Light microscopy