ARTHRITIS & RHEUMATISM Vol. 50, No. 3, March 2004, pp 882–891 DOI 10.1002/art.20093 © 2004, American College of Rheumatology Sjo ¨gren’s Syndrome Associated With Systemic Lupus Erythematosus Clinical and Laboratory Profiles and Comparison With Primary Sjo ¨gren’s Syndrome Menelaos N. Manoussakis, 1 Chryssoula Georgopoulou, 1 Elias Zintzaras, 2 Marilyn Spyropoulou, 3 Aikaterini Stavropoulou, 3 Fotini N. Skopouli, 4 and Haralampos M. Moutsopoulos 1 Objective. To address the clinical, serologic, pathologic, and immunogenetic features of sicca syn- drome that occurs in systemic lupus erythematosus (SLE), as well as its similarities to, and differences from, sicca syndrome that occurs in primary Sjo ¨gren’s syndrome (SS). Methods. A cohort of 283 consecutive unselected SLE patients was evaluated for the presence of associ- ated 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 signifi- cantly 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 sub- group of patients with distinct clinical, serologic, patho- logic, and immunogenetic features, in whom SS is expressed as an overlapping entity and is largely similar to primary SS. Sjo ¨gren’s syndrome (SS) is a chronic autoimmune disorder of the exocrine glands with associated lympho- cytic infiltration of the affected glands. Dryness of the mouth and/or the eyes, resulting from involvement of the salivary and lacrimal glands, is most often present (1). The exocrinopathy may be encountered alone or in the presence of another autoimmune disorder. Features of SS may be found in almost every autoimmune rheumatic disease, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), scleroderma, and others (1). With regard to the patho- genesis, it is unclear whether this form of SS associated with another autoimmune rheumatic disease represents a distinct overlapping entity or a manifestation in the clinical spectrum of the accompanying rheumatic disor- der (2). In fact, comparisons of the clinical, serologic, and immunogenetic features of patients with SS who have no evidence of another autoimmune disease and 1 Menelaos N. Manoussakis, MD, Chryssoula Georgopoulou, MD, Haralampos M. Moutsopoulos, MD, FACP, FRCP (Edin): School of Medicine, National University of Athens, Athens, Greece; 2 Elias Zintzaras, MSc, PhD: School of Medicine, Biomathematics Unit, University of Thessaly, Larissa, Greece; 3 Marilyn Spyropoulou, MD, Aikaterini Stavropoulou, MD: National Tissue Typing Center, George Gennimatas General Hospital, Athens, Greece; 4 Fotini N. Skopouli, MD: Harokopio University, Athens, Greece. Address correspondence and reprint requests to Menelaos N. Manoussakis, MD, Department of Pathophysiology, Medical School, University of Athens, 75 Mikras Asias Street, Athens 115 27, Greece. E-mail: menman@med.uoa.gr. Submitted for publication October 8, 2002; accepted in re- vised form December 3, 2003. 882