Sjögren Syndrome in Systemic Lupus Erythematosus: A Subset Characterized by a Systemic Inflammatory State

Abstract

Objective.An often-neglected subset of patients with systemic lupus erythematosus (SLE) is those with secondary Sjögren syndrome (SLE-sSS). Further, primary SS overlaps and can be difficult to delineate from SLE. To shed light on the SLE-sSS subset, we investigated a large and well-characterized SLE cohort, comparing patients with SLE-sSS and SLE patients without SS (SLE-nonsSS) and controls.Methods.We included 504 consecutive patients with SLE, fulfilling the 1982 revised American College of Rheumatology criteria, and 319 controls from the general population, matched for age and sex to the first 319 patients. SLE-sSS was defined according to the American-European Consensus Criteria (AECC). A thorough clinical examination, including subjective and objective quantifications of sicca symptoms, was performed in all participants. Autoantibodies and 20 selected cytokines were measured by luminex and multiplex analysis, respectively.Results.SLE-sSS, as defined by AECC, occurred in 23% of the patients with SLE. In comparison to SLE-nonsSS, the SLE-sSS group was older and more frequently female. Leukopenia and peripheral neuropathy were more frequent and nephritis less frequent. Circulating levels of 6/20 investigated proinflammatory cytokines [tumor necrosis factor-α, interleukin (IL) 6, monocyte chemoattractant protein 4, macrophage inflammatory protein 1β, IL-12/IL-23p40, and interferon γ–induced protein 10], total IgG, anti-SSA/Ro52, anti-SSA/Ro60, anti-SSB/La antibodies, and rheumatoid factor (IgM and IgA) were higher in the SLE-sSS group (p < 0.05 for all comparisons).Conclusion.The frequency of SLE-sSS increased with age and affected roughly one-quarter of all patients with SLE. Despite less internal organ involvement, a systemic inflammatory state with high levels of proinflammatory cytokines is present in the SLE-sSS subgroup. This is a novel observation that may affect future understanding and treatment of the SLE-sSS subset.

The Increased Ratio of Blood CD56bright NK to CD56dim NK Is a Distinguishing Feature of Primary Sjögren’s Syndrome

“…These distinct changes of the ratio in different autoimmune diseases may be attributed to their different pathological mechanisms. It has been reported that much similar pathogenesis have existed between patients with pSS and SLE [2,22,26], including the type I and type II IFN system in the innate immune phase, and autoantibodies such as anti-SSA/SSB and antinuclear antibody consistently appeared in both diseases, but not for IgG4-RD.…”

Genetic Association of rs15672 and rs12640056 Polymorphisms with the Susceptibility of Systemic Lupus Erythematosus in a Chinese Population

“…A retrospective study showed a positive rate of secondary Sjögren syndrome (SLE-sSS) in adult SLE was 23%. [30] Further evaluation showed that anti-SSB antibody was associated with alopecia. In anti-SSB positive SLE patients, the incidence of alopecia, serositis and secondary Sjögren's syndrome (sSS) was higher than the negative group.…”

Autoantibodies associated with primary biliary cholangitis are common among patients with systemic lupus erythematosus even in the absence of elevated liver enzymes

“…pSS was included as a comparator group, as the association of pSS with PBC is established [12][13][14]. In addition, pSS shares several clinical features with SLE as well as an enhanced activation of the type I interferon system [15]. Although AIH may be regarded as part of the autoimmune umbrella of SLE, we were surprised of the scarce literature on AILD-associated autoantibodies, especially with emphasis on the multitude of different autoantibodies described and frequently detected in SLE [39].…”

“…However, while knowledge of PBC in relation to primary Sjögren's syndrome (pSS) is well recognized, the co-existence of autoimmune liver diseases (AILD) in SLE has been less studied [8,[12][13][14]. Over time, a subset of approximately 20-25% of SLE cases develop secondary SS at Swedish academic centres [15].…”