Background ISN/RPS classification of lupus nephritis was popular and reliable classification because of its semi-quantitativity of glomerular changes. However, tubulointerstitial involvement and the grade of glomerular sclerosis and of hyaline thrombi which could be poor prognostic factors, were not fully evaluated in this classification.
Objectives To clarify the relationship between pathological evaluation and therapeutic response in lupus nephritis (LN).
Methods According to ISN/RPS classification, samples of renal biopsy (RBx) from 51 patients with LN (35.1 y.o, 46 females) were evaluated. Tubulointerstitial involvement (TII), thorombi and glomerular sclerosis were also assessed. Treatment response at 6 months, 1, 2 and 5 years were evaluated by SLICC renal activity and response index score.
Results Biopsy specimens included 19.5 glomeruli at average, though less than 10 glomeruli were found in 17.6%. The RBx samples were classified into ClassI/II/III/IV/V/VI (1/5/10/26/9/0). TII, thrombi and glomerular sclerosis were found in 60.8%, 21.6% and 58.8% of the specimens, respectively. These findings were negatively correlated with complete response (CR) rate. The existence of TII and glomerular sclerosis significantly influenced the CR rate at 6 onths. The finding of thrombi was a significant poor prognostic factor identified at 2 years. Corticosteroids (CS) and cyclophosphamide (CY) was chosen as the first line agents as the induction therapy. Initial dose of CS was increased with higher frequency of pulse therapy against Class III and IV after 2004. Similarly, intravenous infusion with CY was more frequently used for Class III, IV and V after 2004 than before. Complete response rate at 2 years was 70.0% and 46.2% in class III and IV, respectively.
Conclusions Tubulointerstitial involvement and glomerular sclerosis might reflect the response of an induction therapy. Thrombi might influence long-term treatment outcome.
Petri M, et al. Arthritis Rheum 2008;58(6):1784-1788
Disclosure of Interest None Declared