The Rate of Serious Infections in Systemic Lupus Erythematosus Patients is Increasing

Researchers at the National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health (NIH) and the School of Medicine, University of Athens in Greece have recently revealed that hospitalization rates due to serious infections in patients with systemic lupus erythematosus (SLE) have increased significantly. The study was published in the journal Arthritis Care & Research and is entitled “Burden of serious infections in adults with systemic lupus erythematosus. A national population-based Study, 1996-2011.”

SLE is a severe autoimmune disease in which the body’s own immune system overreacts and attacks healthy joints and organs. Individuals with SLE are at a higher risk for infections, since the body’s immune system is de-regulated and because SLE patients often take immunosuppressive medication to control an overactive immune system. Serious infectious diseases are known to be major causes of morbidity and mortality in SLE patients, accounting for about 13 to 37% of hospitalizations and one-third of deaths. The most commonly reported infections in these patients are pneumonia, urinary track and skin infections, whereas bacteremia and sepsis are the main causes of in-hospital mortality.

In order to characterize the incidence of infections in SLE patients, researchers compared the hospitalization rates due to serious infection and in-hospital mortality in the period of 1996 – 2011 between SLE patients and the general population. Data from the Nationwide Inpatient Sample (NIS) was used, which is the largest inpatient care database in the United States containing information on more than 7 million hospital stays. Hospitalizations due to bacteremia/sepsis, pneumonia, skin infections, urinary tract infections and opportunistic infections were considered.

Researchers found that in 1996, the most common serious infection resulting in hospitalizations among SLE patients was pneumonia (4,382 patients), followed by sepsis (2,305 patients), skin infections (1,422 patients), urinary tract infections (643 patients), and opportunistic infections (370 patients). The hospitalization rates for these serious infections were found to be higher in SLE patients compared to the general population, and the risk of developing these infections increased over time, becoming more than 12 times higher in SLE patients in 2011 compared to individuals without SLE. The in-hospital mortality risk was found to be higher in SLE patients only in the case of opportunistic infections. The mortality risk associated to pneumonia and sepsis, was also found to be higher among SLE patients who required mechanical ventilation.

The team concluded that there was a significant increase in hospitalization rates due to serious infections in lupus patients between 1996 and 2011, although the reasons for this increase remain unclear. In-hospital mortality was found to be higher among SLE patients with opportunistic infections, and among those with pneumonia or sepsis who required mechanical ventilation.

The research team believes that the adoption of guidelines to prevent and manage infections in SLE patients is needed. An early diagnosis and adequate treatment of these infections is also required to reduce further health-related consequences in SLE patients.