THU0362 Incidence of major infections in patients with systemic lupus erythematosus
Authors: K. Yap, L. Kyi, J. Chang, P. Nguyen, R. Kandane-Rathnayake, A. Hoi
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Major infections are one of the leading causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE), and one of key concerns when considering the risk of immunosuppressive therapy. Previous studies have limited information on the relationship of infections and disease characteristics. <h3>Objectives</h3> To examine the incidence of major infections and describe the types of infections that occur in a cohort of well-characterised SLE patients <h3>Methods</h3> The study included 192 SLE patients who attended the Monash Lupus Clinic at Monash Health and enrolled in the Australian Lupus Registry and Biobank (ALRB) between 1st of July 2009 to 31st Dec 2016 Major infections were defined as any serious infections resulting in hospitalisation, reactivation of major viral infection, latent or active tuberculosis or any opportunistic infections. Patient and disease characteristics were examined in patients with or without major infections, and comparison was also made with 86 rheumatoid arthritis (RA) patients who are on similar level of immunosuppression. Associations between a number of patient and disease variables and infection were examined using Wilcoxon rank-sum tests (continuous variables) and Person's chi-squared tests (binary/categorical variables). <h3>Results</h3> 57 (30%) SLE patients reported 97 episodes of infection during the observation period (974 person-years). The median age of patients and observation period and other demographics were similar in patients who have experienced a major infection. In contrast, 15 (17%) RA patients reported 28 infection events during the study period. RA patients who reported infections were significantly older than SLE patients with infections events, median age (IQR) 68 years<sup><sup>63, 74</sup></sup> vs 42 years<sup><sup>33, 54</sup></sup> (p&lt;0.001) respectively. 61% of SLE patients and 54% of RA patients were on prednisolone. Comparing lupus with RA patients, the type of pathogens identified was significantly different (p&lt;0.001), with no organism identified being the most common in lupus whereas in RA multiple pathogens are common (table 1). VZV reactivation causing shingles was the most common skin and soft tissue infection in lupus patients, and occurred more frequently than the RA patients. Among all of serious infections requiring hospitalisation, infection site did not differ between SLE and RA patients, and lower respiratory and urinary tracts were most commonly involved. In patients who experienced major infection they had a significantly higher SLEDAI (p 0.04), higher ESR (p 0.005) and lower haemoglobin (p 0.003). <h3>Conclusions</h3> Our data suggests that major infections occur commonly in SLE patients, and the likelihood of infection is higher in SLE, when compared to RA patients on a similar level of immunosuppression. Higher disease activity measures were associated with increased likelihood of infection. Medication exposure such as prednisolone use was similar in SLE and RA patients, suggesting other factors other than medication use plays an important role in driving infections. <h3>Disclosure of Interest</h3> None declared