Background In 1983 Austin et al. informed a series of prognostic factors (including histology) associated with the development of renal failure in patients with lupus nephritis (LN). Differences in actual therapies may have different hazard ratios of renal failure than the described by Austin et al.1
Objectives To evaluate histological factors associated with a decline in kidney function (DKF) in patients with SLE.
Methods We evaluated all the patients in whom a kidney biopsy was performed. DKF was defined as a glomerular filtration rate (GFR) of less than 60 ml/min/m2 in two determinations in the follow-up. Histology was graded according to Austin et al.1 (activity and chronicity) by a renal pathology specialist. Factors associated with the development of DKF were evaluated through Kaplan-Meier curves and Cox regression analysis (bivariate and multivariate).
Results At this moment, we have followed 170 patients with LN and kidney biopsy, 130 (76.5%) women, mean age at kidney biopsy was 29.7±13.2 years; classes of LN were: 71 patients (41.8%) class IV, 30 (17.6%) class V, 22 (12.9%) class III/V, 19 (11.2%) class IV/V, 16 (9.4%) class III, and other classes 12 patients; 135 patients (79.5%) have a minimum follow-up of 12 months. There were statistically significant differences in four groups of LN: pure proliferative (classes III or IV), the combination with membranous (III/IV±V), pure membranous (V) or other classes (Figure1).
In the bivariate analysis, factors statistically significant associated with the development of DKF were: glomerular sclerosis, fibrous crescents, interstitial cell infiltration and tubular atrophy; having membranous component resulted as a “protector” factor for the development of DKF. The Cox regression model included all the factors with a p-value less than 0.25 in the bivariate analysis; independent factors associated with increased HR of DKF were glomerular sclerosis and fibrous crescents; however, hyaline thrombi and presence of membranous nephritis were associated with a decreased HR of DKF. (Table 1).
Conclusions We describe factors associated with a DKF. We found that the proliferative LN in combination with membranous have a better prognosis than pure proliferative LN. Our study could help to evaluate the effects of therapies in LN.
Austin HA, et al. Am J Med 1983;75:382–391.
Disclosure of Interest None declared