Outcome of induction treatment in lupus nephritis: an observational study

Abstract

Background: Recent studies have suggested that MMF may offer an advantage over intravenous cyclophosphamide for induction of lupus nephritis. This study was conducted to compare the outcome of different induction agents.

Objective: To study the outcome of induction treatment in lupus nephritis

Study Design: Cross-sectional observational study consisting of two parts, retrospective and prospective part

Materials and Methods: In the Retrospective part, data were analysed from October 2012 to September 2017 from case records for in-patients in MRD department of SKIMS and from out-patient records of rheumatology division for lupus nephritis. The data included monthly investigations of each patient from the start of treatment for a period of six months. Data was generated from October 2017 to March 2019 for patients diagnosed as lupus nephritis class III/IV/V, under the division of Rheumatology, Department of Internal medicine, SKIMS, Soura, Srinagar. For the prospective part, data was collected containing monthly investigations after the start of induction treatment. Urine examination for sediment, 24 hours urinary protein, and serum creatinine was done monthly. The primary endpoint was complete remission at 6 months, defined as the return to within 10 percent of normal values of serum creatinine levels and proteinuria. A secondary endpoint was partial remission at 6 months, defined as an improvement of 50 percent in serum creatinine and proteinuria. Treatment failure was defined as the failure to reach complete or partial remission at 6 months. No improvement in renal parameters at 3 months was considered a treatment failure.

Results: Of the 47 patients, 11 patients (23.4%) had Class III LN; 27 patients (57.4%) had Class IV LN; 6 patients (12.8%) had Class V LN; 2 patients (4.3%) had Class III+V LN and 1 patient (2.1%) had Class IV+V LN. Among 47 patients, 22 patients (46.8%) received cyclophosphamide, 20 patients (42.6%) received MMF and 5 patients (10.6%) received Tacrolimus. Among 47 patients, 37 patients (78.7%) have not any induction treatment for lupus nephritis previously, 6 patients (12.8%) had received MMF previously, 3 patients (6.4%) had received cyclophosphamide, and 1 patient (2.1%) had received Tacrolimus previously. Among 22 patients who received cyclophosphamide, 5 patients (22.7%) showed complete remission, 9 patients (40.9%) showed partial remission, 7 patients (31.8%) showed treatment failure, and one patient (4.5%) was non-compliant. Among 20 patients who received MMF, 5 patients (25%) showed complete remission, 7 patients (35%) showed partial remission, 8 patients (40%) showed treatment failure. In the Tacrolimus group, out of 5 patients, 1 patient showed complete remission, and 4 showed partial remission.

Conclusion: The response to induction treatment between cyclophosphamide and MMF showed a higher failure rate in the MMF group compared to the Cyclophosphamide group (40% vs.31.8%) . The percentage of complete response was slightly higher in the MMF group compared to the CYC group (25% vs.22.7%) , but the percentage of partial response was again lower in the MMF group as compared to the cyclophosphamide group (35% vs.40.9%) , favouring cyclophosphamide slightly better than MMF in our study population as two out of three endpoints of our study favour comparatively better outcome of cyclophosphamide. Treatment in lupus nephritis has better results for MMF so far as a complete response is concerned, but cyclophosphamide outscores MMF for Partial remission and has a better outcome than MMF so far as the failure rate is concerned.

Implications: In our study population, two out of three endpoints favoured cyclophosphamide better than MMF for the induction treatment in lupus nephritis.