Objective To observe the clinical efficacy and safety of leflunomide for refractory lupus nephritis who failed in conventional treatment.

Methods Twenty-seven refractory systemic lupus erythematosus patients were enrolled as study objects, and were treated with leflunomide (20 mg/dor 30 mg/d)and glucocorticoid (10 to 15 mg/d). The rate of clinical remission, Systemic Lupus Erythematosus Disease Activity index (SLEDAI) score, 24-hour urine protein quantification, serum albumin, anti-dsDNA antibody, immunoglobulin G (IgG) and changes of serumcomplement after 24 weeks of treatment were observed, and adverse events were recorded.

Results After 24 weeks of treatment, 6 patients(22.22%) received complete remission and 11 patients(40.74%) received partial remission, and the total remission rate was 62.96%. The SLEDAI score of the patients decreased from 5 (4, 8) points before treatment to 4 (0, 4) points, and the difference was statistically significant (P < 0.01). The 24-hour urine protein of the patients was (4.36±0.82) g before treatment and (2.07±0.46) g after 24 weeks of treatment. The serum albumin level was (26.20±2.30) g/L before treatment and (37.31±5.84) g/L after 24 weeks of treatment. Compared with before treatment, the 24-hour urine protein level after 24 weeks of treatment in patients decreased and the serum albumin level increased (P < 0.01). There were no significant differences in the levels of anti-dsDNA, IgG, C3 and C4 before and after treatment (P>0.05). The adverse events mainly included gastrointestinal symptoms, alopecia, leukopenia and liver function damage. The symptoms disappeared or improved during the withdrawal period.

Conclusion Leflunomide can be used for salvage treatment of refractory lupus nephritis, and it is helpful to reduce proteinuria. Most of the adverse events are mild to moderate degree, and the treatment is tolerable and inexpensive.