RESUMEN
AIM: TO assess the effects of rituximab (RTM) therapy on clinical and morphologic activity of lupus nephritis (LN). MATERIAL AND METHODS: The study included 45 patients with confirmed diagnosis of systemic lupus erythematosus (SLE), unaffected by previously received standard therapy with glucocorticoids (GCs) and cytostatics. The disease activity was assessed using Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI 2K); to assess the LN activity we used the SLICC RA/RE index. Forty-five patients with LN were given puncture renal biopsy prior to prescribing RTM; 16 patients had repeated renal biopsy 1 year and more after beginning the anti-B-cell therapy. LN was graded histologically in accordance with the WHO classification (2003) with indices of activity (AI) and chronicity (CI). RESULTS: The predominant number of patients had class III - IV of LN. The repeated renal biopsies demonstrated that LN had undergone a transition into a more favourable morphologic class, which was associated, in most of these cases, with a positive therapeutic effect. The follow-up dynamics showed a statistically significant reduction of AI (p=0.006), and no statistically significant changes in the CI (p = 0.14). CONCLUSION: The long-term follow-up in the study has showed that repeated courses of anti-B-cell therapy with RTM have a positive effect both on SLE activity and generally on the renal process. The reduction of the morphologic class of LN as assessed in the repeated renal biopsies is a convincing proof for this. Eleven out of 16 patients experienced transition of the morphologic class into a more favourable type, which in most cases was combined with lower AI (p = 0.006). We found no evidence of increase in the CI (p = 0.14).