"Pseudoseptic" arthritis complicating rheumatoid arthritis: a report of six cases.

Six cases of a severe, sterile, inflammatory arthritis mimicking septic arthritis occurred in 328 patients with rheumatoid arthritis (RA) over a 4-year period. Four patients were poorly controlled by or had recently discontinued a disease modifying antirheumatic drug. Five improved after receiving increased glucocorticoid therapy. Radiographs showed no accelerated joint destruction after a mean followup of 29.5 months (range 8-49). Recognition of "pseudoseptic" arthritis occurring in the course of RA permits appropriate therapy and avoids extended antibiotic treatment.