To evaluate the risk and protective factors of serious infection (SI) in patients with systemic lupus erythematosus (SLE) after rituximab treatment within 180 days.
SLE patients treated with rituximab were analyzed. SI was defined as any infectious disease requiring hospitalization. The clinical characteristics, laboratory profiles, medications, and incidence rate (IR) were presented. Multivariate Cox proportional hazards models and Kaplan-Meier analysis for risk factors of SI were performed.
A total of 174 SLE patients receiving rituximab treatment were enrolled. The overall IR of SI was 51/100 patient-years. Pneumonia (30.4/100 patient-years), followed by soft tissue infections, intra-abdominal infections, and pneumonia (all 6.1/100 patient-years) were the leading types of SI. Twelve patients died during the 180-day follow-up (crude mortality rate: 14.6/100 patient-years). Chronic kidney disease (CKD), defined as an estimated glomerular filtration rate <60 mL/min/1.73m (hazard ratio [HR]: 2.88, 95% confidence interval [CI]: 1.3-6.38), and a background prednisolone equivalent dosage ≥15 mg/day (HR: 3.5, 95% CI: 1.57-7.78) were risk factors for SI among all SLE patients. Kaplan-Meier analysis confirmed the risk of SI for SLE patients with CKD and a background prednisolone equivalent dosage ≥15 mg/day (log-rank p = 0.001 and 0.019, respectively). Hydroxychloroquine reduced the risk of SI in SLE patients (HR: 0.35, 95% CI: 0.15-0.82; log-rank p = 0.003).
SI was prevalent in SLE patients after rituximab treatment. SLE patients with CKD and high-dose glucocorticoid use required constant vigilance. Hydroxychloroquine may reduce the risk of SI among SLE patients administered rituximab.