Antiproteinuric Effect and Transient Reduction in Kidney Function of Calcineurin Inhibitors in Hispanic Patients with Lupus Nephritis

Background: Systemic lupus erythematosus is an autoimmune disease with common renal involvement. Although current remission inital therapies are effective, a high portion of patients suffer flares or are treatment resistant. Combining immunosuppressants with ICNs may improve clinical response, but scarce data exists for the Hispanic population. Methods: Patients with SLE and (LN) with persistent proteinuria despite previous immunosuppression and who began a combined regimen, including CNI, were included. 24-hour proteinuria and eGFR by CKD-EPI were assess at 6 and 12 months. Results: 239 records from patients with LN diagnosis were evaluated, and 42 met inclusion criteria. At 6 months, 40% of the patients obtained complete (CR), and partial response (PR) was reached by 26% of patients. At 12 months, CR and PR were reached by 44% and 32% of patients respectively. A notable reduction in proteinuria was seen at 6 and 12 months compared to baseline (2.89 vs 1.21 g/d, p < 0.001; vs 0.78 g/d, p< 0.001). A transient reduction in eGFR was detected at 6 months (109 vs 104 ml/min/1.73 m2, p= 0.005), which improved significantly at 12 months (109 vs 117 ml/min/1.73 m2, p=0.002). Conclusion: In Hispanic patients with lupus nephritis who previously used immunosuppressor regimes with partial or no response, the addition of a calcineurin inhibitor can be effective. It attains optimal biochemical response rates despite a brief reduction in eGFR that improves without treatment withdrawal. - Women, n (%) 36 (85%) Age, years [± SD] 35 ± 12 ISN/RPS histological classes, n (%) Class V Class III / IV Class III / IV + V 15 (38.5)14 (35.9)10 (25.6) CNI prescribed, n (%) TacrolimusCyclosporine A 34 (81)8 (19) Concomitant immunosuppressor, n (%) Mycophenolate Azathioprine Prednisone 37 (88)5 (12)42 (100) Proteinuria 24 h(g/24h)Basal6 months12 months 2.8 (0.45-13.5)1.2 (0.03-11.1)0.78 (0.04-4.8) Response Combined No response 14 (66%)28 (33%)