Objectives Infections commonly complicate the course of systemic lupus erythematosus (SLE). Our aim is to investigate the clinical features and potential clinical predictors of infections in patients with SLE.
Methods A retrospective cohort study was performed among patients admitted to the First Affiliated Hospital of Sun Yet-sen University from January 2007 to June 2012. Demographic information, clinical and laboratory data and pathogen were collected. Univariate analysis and logistic regression models were used for the analysis of data.
Results Among 2568 patients included, 1321 (51.44%) were diagnosed with infection, with the average age of 34.97±13.22 years old and the mean duration of SLE was 44.65±65.19 months (range 1-480 months). 1452 infections involving various microorganisms were recorded. Bacterial infection was predominant (49.66%), followed by viral infection (39.12%), fungal infection (7.30%) and Mycobacterium (3.93%) infections. The pulmonary was most commonly affected (37.81%). Less common sites of infection included upper respiratory tract, genitourinary tract, skin/soft tissue and so on. The most frequently found bacteria were Escherichia coli (26.63%), followed by Acinetobacter baumannii (13.43%) and Staphylococcus aureus (11.19%). 32.84% of the isolated bacteria were multi-drug resistant. Herpes zoster was the most common viral infection. The most common fungus was Candida albicans (74 episodes), followed by Candida tropicalis (8 episodes) and Candida glabrata (8 episodes). The mortality (1.74% vs. 0.80%, respectively) and average length of stay (19.88±14.84 days vs. 15.54±9.33 days, respectively) in patients with infection were both significantly higher than those in the patients without infection. The logistic regression multivariate analysis indicated that higher SLEDAI (OR=1.02, 95% CI: 1.00-1.03), lung disease (OR=1.80, 95%CI: 1.16-2.79),nephritis (OR=1.71, 95%CI: 1.45-2.21), anemia (OR=1.38, 95%: 1.13-1.69), elevated CRP (OR=1.04, 95% CI: 1.04-1.05) and treatment with higher dose cyclophosphamide (CYC) (≥1.0 g/m2/month) (OR=2.94,95%CI: 2.24-3.87) were positively associated with the occurrence of infections.
Conclusions Infections were common in SLE patients, which increased both the mortality and average length of stay. The current study demonstrated that higher SLEDAI, lung disease, nephritis, anemia, elevated CRP and treatment with higher dose CYC were associated with the infection. It is concluded that a high level of suspicion and close monitoring of SLE patients with risk factors may ensure an optimal outcome. The judicious use of CYC is critical in limiting infections in SLE patients.
Disclosure of Interest None declared