Corticosteroids are the major contributors to the risk for serious infections in autoimmune disorders with severe renal involvement

Introduction: We sought to investigate the infection profile and associated risk factors in a compiled cohort of patients with autoimmune disorders with severe renal involvement treated with aggressive immunosuppressive (IS) regimens.

Methods: A total of 162 patients with aggressive glomerulonephritis [101 with lupus nephritis (LN), 24 with cryoglobulinemic vasculitis (CryoVasc), and 37 with ANCA-associated vasculitis (AAV)] were retrospectively reviewed for any infection occurrence. Infection incidence, type, site, and grade (1-5) were recorded. Multivariate Cox proportional hazard regression analysis was performed to identify independent risk factors for infections.

Results: A total of 179 infection episodes occurred during a follow-up of 468 patient-years. Eighty-two patients (50.6%) had at least one infection. The incidence rates of infections and severe infections were 38.2 and 14.3 events per 100 patient-years. Patients with AAV had more infections than those with CryoVasc and LN (100.6, 47.5, and 26.6 infections per 100-patient-years, respectively; p = 0.002). Most patients developed infections early during the initial induction therapy (62.1% in the first 6 months of follow-up). In multivariate Cox regression analysis, high-dose oral corticosteroids (≥ 0.5 mg/kg/day in the first month of induction therapy) was an independent predictor of any infection (HR 2.66; 95% CI, 1.5-4.73), severe infections (HR 2.45; 95% CI, 1.03-5.82), and pulmonary infections (HR 2.91; 95% CI, 1.05-8.01). Pulmonary involvement increased the risk for pulmonary infections (HR 3.67; 95% CI, 1.32-10.1) and severe infections (HR 2.45; 95% CI, 1.01-5.92).

Conclusion: Infections occur frequently with current IS regimens in aggressive glomerulonephritis. Pulmonary involvement and high-dose corticosteroid regimen were the most significant risk factors for infections. Key Points • Infections occur frequently with current immunosuppressive regimens in autoimmune aggressive glomerulonephritis. • High-dose corticosteroids are the major contributors to the risk for serious infections.