Background There are scanty data about infection in Systemic Lupus Erythematosus (SLE) patients from large multicenter cohorts.
Objectives To describe the prevalence of severe infection (SInf), investigate associated factors and clinical meaning in a large SLE cohort from Spanish Rheumatology Society Lupus Registry (RELESSER).
Methods Patients with Sinf were compared with patients without SInf in terms of severity, damage, comorbidities and demographic characteristics (bivariate analysis and Cox regression to survival until the first infection).
Results A total of 3.658 SLE patients included, 90% female, median age 32.9 years (DQ 9.7), 93% Caucasian and 5% Hispanic (Amerindian,mestizo). Mean follow-up (months) was 120.2 (SD: ±87.6). A total of 705 (19.3%) of the patients suffered ≥1 SInf, with an overall of 1.227 SInf. The density of incidence was 29.2 (95%CI: 27.6 - 30.9) infections/ 1000 patients-year. The survival until second infection was lower than survival until first infection (log rank p<0.000). There was predominance of bacterial cause (51.9%), with a 30.4% of unknown cause, and the respiratory tract was the most frequent localization 35.5%. A total of 208 (5.7%) patients died during the follow-up period, 24.5% of them by infection. The predominant localization for the fatal infection was the circulatory stream (bacteraemia/sepsis) (42.0%). In the Cox proportional-hazards regression model age at diagnosis (HR 1.016; 95%CI: 1.009-1.023, p=0.0000) Hispanic ethnic (HR 2.151; 95%CI: 1.539-3.005 p=0.0000) corticosteroids (≥10 mg/day) (HR 1.271; 95%CI: 1.034-1.561, p=0.0224) immunosuppressors (HR 1.348; 95%CI: 1.079-1.684 p=0.0085), hospitalization by SLE (HR 2.567; 95%CI: 1.905-3.459, p=0.0000) renal involvement (HR 1.370; 95%CI: 1.130-1.660, p=0.0013), severity Katz index (SKI) (HR 1.160; 95%CI: 1.105-1.217, p=0.0000), damage index (SDI) (HR 1.069; 95%CI: 1.031-1.108, p=0.0003) and tobacco (HR: 1.332; 95%CI: 1.121-1.583, p=0.0011) were all associated with SInf. Time on antimalarials (months) proved to be protective (HR: 0.998; 95%CI: 0.997-0.999, p=0.0022)
Conclusions SInf remains a frequent and potentially fatal complication of SLE and/or immunosuppressive therapies, and it's a marker of more severe disease. Respiratory bacterial infections are the most common SInf in SLE, but bloodstream infections are the most common mortal ones. A previous infectious event seems to increment the risk of a subsequent infection in SLE. SInf are more common in male and Hispanics and is associated age, tobacco use and other co-morbidities. Antimalarials use exerts a time-dependent protective effect
Disclosure of Interest None declared
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.