What are the risk factors for severe infections in hospitalized SLE patients?

Among hospitalized patients with systemic lupus erythematosus (SLE), factors such as low immunoglobulin, anti-dsDNA antibody positivity, and cyclophosphamide use contribute to an increased risk of recurrent severe infections, according to a study.

A total of 1,051 first hospitalized SLE patients were recruited for the study. Of these, 164 patients (15.6 percent) had severe infection on admission.

Over a median follow-up of 4.1 years, severe infection outcomes were documented in 113 patients (10.8 percent), including 27 with reinfection and 86 with initial severe infection (16.5 percent vs 9.7 percent, p=0.010). Of note, those with baseline severe infection had a higher cumulative incidence of reinfection (p=0.007).

In a multivariable analysis, the risk of severe infection (especially initial severe infection) was high in the presence of renal involvement, elevated serum creatinine, hypoalbuminemia, cyclophosphamide, and mycophenolate mofetil treatment. Meanwhile, the risk of recurrent severe infection was associated with low immunoglobulin (hazard ratio [HR], 3.15, 95 percent confidence interval [CI], 1.22–8.14), anti-dsDNA antibody positivity (HR, 3.60, 95 percent CI, 1.56–8.28), and cyclophosphamide use (HR, 2.14, 95 percent CI, 1.01–5.76).

Moreover, baseline severe infection and low immunoglobulin had an additive effect on the risk of reinfection (HR, 3.91, 95 percent CI, 1.27–12.09).