"Rheumatoid" Nodules in Systemic Lupus Erythematosus

Six patients with systemic lupus erythematosus (SLE) and periarticular subcutaneous nodules are described. The nodules were biopsied in three patients. Each specimen was histologically typical of the well-developed "rheumatoid" nodule. The features of SLE in these patients included fever, constitutional symptoms, polyarthritis, skin rash, serositis, glomerulonephritis, anemia, and leukopenia. All had lupus erythematosus cells, antinuclear antibodies, and reduced serum complement. The latex test was negative in three patients and only transiently positive in the other three. When present, the subcutaneous nodule was invariably associated with clinically active SLE. In the patient with polyarthritis the presence of periarticular subcutaneous nodules may be a hallmark of SLE as well as rheumatoid arthritis.