A national cohort study examined the risk of severe infection and infection-related mortality in patients with chronic kidney disease with lupus nephritis in comparison to other chronic kidney disease etiologies.

Abstract

The co-occurrence of lupus nephritis (LN) and chronic kidney disease (CKD) is associated with an excess risk of infection. However, it remains unknown whether the infection risk differs between LN with moderate and advanced CKD (LN-CKD) and other CKD etiologies. Using data from the Swedish Renal registry 2006-2021, we identified 14,128 patients (median age 68 years, 64% men, median estimated glomerular filtration rate 25 ml/min per 1.73m²) that included 317 patients with LN-CKD, 783 patients with anti-neutrophil cytoplasm antibodies (ANCA) vasculitis , 8877 patients with diabetic kidney disease (DKD), 1855 patients with autosomal dominant polycystic kidney disease (ADPKD) and 2296 patients with primary glomerular disease (PGD). Multivariable Poisson models and cause-specific Cox proportional hazards regressions were used to compare the risk of all-cause- and site-specific infection-related hospitalizations (including sepsis, respiratory-, genitourinary-, gastrointestinal related infections and infection of other/unspecified sites), and death due to infection, between patients with LN-CKD and the other CKD etiologies. In LN-CKD, the three-year absolute risks of all-cause infection-related hospitalization and death due to infection were 31% and 4% respectively. The risk of all-cause infection-hospitalization was higher in LN-CKD than in ANCA vasculitis but similar between LN-CKD and DKD. LN-CKD was associated with a higher risk of all-cause infection-related hospitalization and death due to infection than ADPDK (adjusted hazard ratio 1.46 [1.18-1.8] and 2.47 [1.35-4.5], respectively) and PGD (1.90 [1.54-2.34] and 2.97 [1.71- 5.18], respectively). The results were consistent across the site-specific infection-related hospitalizations. Patients with LN exhibited a higher risk of severe infection compared to patients with ANCA vasculitis, ADPKD and PGD. LN-CKD and DKD had similar infection-risks. This highlights the need for prevention and tailored immunosuppressive therapy in the LN-population with CKD.