Sjögren's syndrome associated with systemic lupus erythematosus: Clinical and laboratory profiles and comparison with primary Sjögren's syndrome

Abstract

Objective.To address the clinical, serologic, pathologic, and immunogenetic features of sicca syndrome that occurs in systemic lupus erythematosus (SLE), as well as its similarities to, and differences from, sicca syndrome that occurs in primary Sjögren's syndrome (SS).Methods.A cohort of 283 consecutive unselected SLE patients was evaluated for the presence of associated SS using the American–European classification criteria. Clinical and laboratory parameters in SLE patients with SS (SLE–SS) were compared with those in SLE patients without SS (SLE–no SS) and with a group of 86 unselected patients with primary SS.Results.SS was identified in 26 SLE patients (9.2%); the SS preceded the development of lupus in 18 of them (69.2%). Compared with the SLE–no SS group, patients with SLE–SS were significantly older, had a higher frequency of Raynaud's phenomenon, anti‐Ro/SSA, anti‐La/SSB, and rheumatoid factor, but had a significantly lower frequency of renal involvement, lymphadenopathy, and thrombocytopenia. Compared with the primary SS group, SLE–SS patients displayed a clinically similar sicca syndrome, but were significantly younger and had an increased frequency of perivascular infiltrates in the salivary glands associated with anticardiolipin antibodies in the serum. SLE–SS patients had a high frequency of the DRB1*0301 allele. This HLA profile distinguished the SLE–SS group from the SLE–no SS group, who had an increased frequency of DRB1*1501 and DQB1*0602 alleles, but was similar to the HLA profile of the primary SS group, who had an increased frequency of DRB1*0301.Conclusion.SLE–SS appears to constitute a subgroup of patients with distinct clinical, serologic, pathologic, and immunogenetic features, in whom SS is expressed as an overlapping entity and is largely similar to primary SS.

Deficiency of Act1, a critical modulator of B cell function, leads to development of Sjögren's syndrome

“…The rheumatoid factor (RF), commonly found in autoimmune diseases such as SLE and SS [4,5,25,26], was also detected in Act1-deficient mice but not in their littermates (Fig. 4B).…”

“…Sjögren's syndrome (SS) is a systemic autoimmune disorder characterized by profound lymphocytic infiltration of the lacrimal and salivary glands [3][4][5]. This chronic inflammatory process leads to diminished function of the glands resulting in symptoms of xerophthalmia (dry eyes) or xerostomia (dry mouth).…”

“…This chronic inflammatory process leads to diminished function of the glands resulting in symptoms of xerophthalmia (dry eyes) or xerostomia (dry mouth). B cell hyper-activation is a predominant feature of SS, which in human patients is characterized by hypergammaglobulinemia and production of autoantibodies [3][4][5][6][7]. The occurrence of SS-A/Ro and SS-B/La, the two most commonly detected autoantibodies in SS patients, has been directly associated with recurrent lymphocyte infiltration of the exocrine glands, tissue damage and secretory dysfunction.…”

“…SS is classified as primary or secondary depending on the absence or presence of conjunction with other systemic autoimmune diseases such as systemic lupus erythematosus (SLE), which is characterized by production of anti-nuclear autoantibodies and immune complex deposition in the kidney. Kidney failure, as a result of lupus nephritis is the leading cause of mortality in human patients with SLE [4].…”

Additive effects of the major risk alleles of IRF5 and STAT4 in primary Sjögren's syndrome

“…Primary SS and SLE with secondary SS have a common genetic background, with a high frequency of the HLA-DRB1*0301 allele. 2 Early association studies of candidate genes outside the HLA-locus in primary SS have been small and have obtained conflicting results.…”