THERE is an area in the spectrum of rheumatoid arthritis and systemic lupus erythematosus (SLE) where the overlapping of clinical and serologic findings makes objective differentiation difficult. From 3% to 27% of adult patients with rheumatoid arthritis have been reported to show lupus erythematosus (LE) cells in the blood.1-4 Conversely, an atypical picture of deforming rheumatoid-like arthritis with positive tests for rheumatoid factor has been reported to occur frequently in adult cases of SLE.4-7 In contrast, Ansell and Bywaters8 found one case with positive LE cell factor in a series of 60 children with rheumatoid arthritis. Others9 have reported no positive rheumatoid factor test results in children with SLE. The purpose of this study was to test the hypothesis that clinical and immunologic evidence of both rheumatoid arthritis and systemic lupus erythematosus might occur in the same patients in childhood.
Materials and Methods
This study was