Correlation between histological findings, activity & choronicity indices and laboratory data in patients with lupus nephritis

Renal involvement in systemic lupus erythematosus (SLE) is one of the most serious complications. Numerous reports have documented the unpredictable course of lupus nephritis and the role of renal biopsy in evaluation of individual patients. It is impossible to predict the types, severity and activity of renal lesions based only on combination of clinical and laboratory findings. The aim of this study was to evaluate the histological findings, activity and chronicity scores, and also assessing the correlation between histology and other laboratory findings in patients with lupus nephritis. This cross-sectional study was carried out on 40 patients with diagnosis of lupus nephritis at Ghaem Hospital in Mashhad during 2003 to 2006. Renal biopsy was performed for all patients and correlation between laboratory and serologic parameters and the histological findings were investigated. Data were analyzed using t-test, Chi square test, and Fischer exact test. Activity score was 9.02 in 34 patients with proteinuria and 6.33 in 6 patients without proteinuria (p=0.018). There was a significant correlation between the activity score and serum C4 levels (p=0.031). Also, a significant correlation was shown between fibrous crescent (one of the chronicity criteria on biopsy) and nephrotic syndrome (p=0.047). No significant correlation between activity and chronicity scores and other laboratory and serologic findings was found. Based on our data, no exact correlation between histological findings and laboratory data in lupus nephritis was demonstrated therefore, emphasis on important role of renal biopsy in evaluation of these patients is suggested.