Infections in ANCA-associated vasculitis and lupus nephritis treated with rituximab

Objective: Patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and systemic lupus erythematosus (SLE) are prone to infections. This study aims to clarify infectious complications in terms of both the disease and the specific treatments used. Patients and Methods: Sixty-three patients with SLE and AAV with kidney involvement treated with rituximab or cyclophosphamide were included. Patients were examined regarding infections, comorbidities, immunosuppressives, estimated glomerular filtration rate (eGFR), use of prophylactic antibiotics, hospitalization, and death. Results: Patients with SLE experienced more genitourinary infections in general (p=0.009). In the rituximab group, SLE patients had a higher incidence of genitourinary infections, septicemia, and intensive care unit admissions. Furthermore, lupus patients with serious infections were all treated with rituximab and had a higher incidence of low respiratory tract infections (p=0.003). On the contrary, treatment with rituximab did not cause an increased risk of infection among AAV patients compared to cyclophosphamide. In general, patients with serious infections had lower IgG and total Ig levels (p