Serial renal biopsy in systemic lupus erythematosus

Objective. To examine the role of sequential renal biopsies in patients wit h systemic lupus erythematosus (SLE), with regard to indications, morpholog ic change over time, and the clinical utility of repeat biopsies. Methods. Patients with repeat renal biopsies were identified from the Unive rsity of Toronto Lupus Clinic Database and their biopsies were reviewed bli ndly by a committee, using the WHO classification as well as activity and c hronicity indices. Reasons for obtaining biopsy were documented, and therap eutic decisions following repeat biopsy were tabulated. Results. Fifty-seven patients (49 F/9 M) had at least 2 renal biopsies betw een 1970 and 1994. The mean interval between biopsies was 4.2 years. The ma jor reason for obtaining the first biopsy was disease diagnosis (32/57), wh ile the majority of repeat biopsies were performed to discern the cause of increasing proteinuria (45/57). A comparison of the WHO classification of i nitial and repeat biopsies showed evolution to another class in 23 instance s, but more commonly a change within a class was seen. A decrease in prolif erative lesions (classes III and IV and subsets of V) was noted on repeat b iopsies. The chronicity index increased significantly (p = 0.0001) and the activity index decreased (p = 0.064) between biopsies. Seventy-seven percen t of patients had a change in treatment based on biopsy results. Conclusion. The major reason for repeat renal biopsy in patients with SLE w as proteinuria. Renal morphology in patients with SLE can change with time, particularly in terms of chronicity and activity features. Repeat biopsies in patients with SLE appear to have clinical utility.