#6452 SEVERE INFECTIONS AND IMMUNOSUPPRESSIVE MAINTENANCE THERAPY IN PATIENTS WITH LUPUS NEPHRITIS: DATA FROM A SINGLE CENTER PROSPECTIVE STUDY
Authors: Stroie Anna Mirela , Penescu Mircea , Paul Balanescu 
Published: June 2023

Abstract

Background and Aims
Systemic lupus erythematosus is a multi-organ, multi-systemic autoimmune disease with significant burden on generally young patients. Renal involvement is relatively frequent, recent studies cite a prevalence of 15-60% of patients, and 25% develop end-stage renal disease after 10 years of disease onset. We studied the incidence of severe infections in 67 lupic patients with biopsy proven lupus nephritis treated with immunosuppressive maintenance therapy: mycophenolate mofetil, azathioprine, calcineurin inhibitors associated with corticosteroids. Severe infections are a major cause of death in lupic patients.

Method
We concluded a single center prospective study to assess the incidence of severe infections in patients with biopsy proven lupus nephritis. Patients received standard induction therapy (Eurolupus, NIH, MMF, CNIs induction regimens) and were assigned to maintenance therapy to either AZA, MMF, CNIs or patients who received both AZA and MMF in the course of the disease (a switch in therapy was made), alongside standard doses of corticosteroids. We used SPSS version 16 for the statistical analysis and data was extracted from the electronical medical records.

Results
We included patients diagnosed with systemic lupus erythematosus who had renal biopsy performed between January 2008 – December 2018. Patients were followed-up until May 2020. We included 67 patients, out of which 58 patients were female (86.5%). Median age at diagnosis of lupus disease was 29 years (min 10 years, max 62 years). Median duration of the disease was 10 years (min 1.5 years, max 30 years). Median duration of corticosteroid treatment was 10.1 years (min 1.58 years, max 29). 1 patient had class I, 2 had class II, 12 had class III, 32 had class IV, 12 had class V, 1 had class VI, 1 had classes III+V, 1 had classes IV+V of lupus nephritis (ISN classification of lupus nephritis). The induction regimens received by the patients were Eurolupus (21 patients), NIH (23 patients), MMF (14 patients) and CNIs (9 patients). Treatments administered for the maintenance period were MMF (5 patients), AZA (27 patients), CNIs (9 patients), and patients who had a switch in therapy, receiving both MMF and AZA during the study (26 patients) due to financial reasons, pregnancies, adverse effects, patient prefference. We registered severe infections in 16 patients – 3 patiens had severe viral infectios, 9 had bacterial and 4 had both viral and bacterial severe infections. We did not obtain statistical significance (Chi square statistics = 1.568, p = 0.66) for the association of a specific immunosuppressive treatment modality with infection development. In our study, the duration of administration of each immunosuppressive therapy expressed in years was not associated with the number of severe infections (Independent-Samples Mann-Whitney U Test, p&gt;0.05).

Conclusion
We could not identify significant differences regarding infection rates in patients treated with MMF, AZA, CNIs or MMF and AZA. We therefore suggest that all patients receiving the immunosuppressive regimens described should be considered at equal risk of severe infections.