Although patients with incomplete lupus erythematosus characteristically present with milder symptoms, some patients develop more serious clinical manifestations requiring more aggressive immunomodulatory therapy, according to findings published in Arthritis Care and Research.
The researchers additionally concluded that longitudinal studies are needed to understand how incomplete lupus erythematosus (ILE) affects organ damage as well as potential risk for transition to systemic lupus erythematosus (SLE).
Although patients with incomplete lupus erythematosus usually present with milder symptoms, a subset of patients may develop more serious clinical manifestations and require more aggressive treatment.
“Patterns of immune dysregulation in ILE are suspected to coincide with those observed in SLE,” Teresa Aberle, PA, of the Oklahoma Medical Research Foundation, in Oklahoma City, and colleagues wrote. “For example, lupus-associated autoantibodies and soluble mediator dysregulation accumulate prior to clinical SLE onset; these autoantibodies are also observed in ILE, and there is some evidence of soluble mediator dysregulation.”
“However, unique immunologic features that distinguish SLE patients from ILE patients or define subsets of ILE patients may influence their disease course,” the researchers wrote. “Therefore, focused studies are needed to understand the relationships between autoantibody positivity, soluble mediators, and clinical disease in ILE patients and ILE patient subsets.”
To examine the clinical manifestations, medication history and immunologic features in a variety of ILE and SLE patients, the researchers analyzed the medical records of those enrolled in the Lupus Family Registry and Repository. They used the American College of Rheumatology classification criteria to identify 440 patients with ILE and 3,397 with SLE, all of whom completed the Connective Tissue Disease Screening Questionnaire.
The researchers measured anticardiolipin and plasma B lymphocyte stimulator (BLyS) using enzyme-linked immunosorbent assay, antinuclear antibodies (ANA) by using indirect immunofluorescence, and 13 autoantibodies by bead-based assays.
According to the researchers, ILE patients exhibited 1.3 autoantibody specificities, compared with 2.6 among SLE patients (P < .0001). Further, ILE patients were less likely to have ANA titers of 1:1,080 or greater (10.5% vs. 19.5%; P < .0001). Among ILE patients, BLyS levels were intermediate (controls < ILE; P = .016; ILE < SLE; P = .008), the researchers said. Pericarditis, renal or neurologic manifestations occurred in 12.5% of ILE patients, and were correlated with non–European American race/ethnicity (P = .012). Although hydroxychloroquine use increased over time, it was less frequent in ILE (65.2%) than SLE (83.1%) patients (P < .0001).
“This study suggests that ILE can potentially be defined through a rubric of clinical and immunologic phenotypes that distinguish ILE from SLE,” Aberle and colleagues wrote. “Although ILE patients exhibit fewer autoantibody specificities and lower BLyS levels than SLE patients, patients with incomplete lupus classification report nearly as many SLE-related symptoms as patients with classified SLE. Moreover, subsets of ILE patients are at risk of permanent organ damage and potential transition to classified SLE.”
The researchers noted that “By establishing and characterizing a large, diverse collection of ILE patients, this study provides a foundation for future longitudinal studies to identify ILE patients at the highest risk of transition to SLE, and to address the impact of ILE on quality of life, organ damage, increased morbidity, and early mortality.” – by Jason Laday
Disclosure: The authors report funding from the NIH National Institute of Allergy and Infectious Disease, the Institutional Development Awards from the National Institute of General Medical Sciences, the National Institute of Arthritis and Musculoskeletal and Skin Diseases, the National Human Genome Research Institute, the National Heart, Lung and Blood Institute, the National Institute of Diabetes and Digestive and Kidney Diseases, and the U.S. Department of Veterans Affairs.