Renal efficacy of calcineurin inhibitors in treatment-resistant lupus nephritis: An experience among Mexican patients from a tertiary referral center

Background Systemic lupus erythematosus (SLE) is an autoimmune disease with frequent renal involvement. Although current remission induction therapies are effective, a high proportion of patients experience flares or are treatment-resistant. Combining immunosuppressants with Calcineurin Inhibitors (CNIs) may improve clinical response, but insufficient data exist for the Hispanic population. Methods Patients with SLE and lupus nephritis (LN) with persistent proteinuria despite previous immunosuppression and who began a combined regimen, including CNIs, were included. 24-hour proteinuria and glomerular filtration rate (eGFR) as estimated by CKD-EPI were evaluated at 12 months and stratified by LN histological class. Results 239 clinical records from patients with LN diagnosis were evaluated, and 42 met the inclusion criteria. At 12 months, complete and partial responses were reached by 26.2% and 35.7% of patients, respectively. Compared with baseline, a significant reduction in proteinuria was observed (2.89 vs 0.72 g/d, p < .001), and a transient decrease in eGFR was detected at 6 months (109 vs 104 mL/min/1.73 m2, p = .001), which improved significantly at 12 months (109 vs 114 mL/min/1.73 m2, p = .023). Conclusion For a Mexican cohort of patients with treatment-resistant lupus nephritis, the addition of CNIs can be effective. It achieves excellent biochemical response rates despite a transient reduction in eGFR that improves without treatment withdrawal.