Rheumatoid arthritis is the major risk factor for septic arthritis in rheumatological settings.
Septic arthritis (SA) is a clinical emergency with considerable morbidity and mortality that can lead to rapid joint destruction and irreversible functional loss. The reported incidence varies from 2-5 cases/100,000 person-years in the general population to 70 cases/100,000 person-years among patients with rheumatoid arthritis. In fact, individuals with rheumatoid arthritis are at particular risk for developing SA. This may be due to several reasons: joint disease predisposes to bacterial joint colonization and RA itself and its treatment with corticosteroids, disease-modifying antirheumatic drugs (DMARDs) and biological therapies may decrease the immune function required for protection from pathogens. Steroids and DMARDs seem to affect the leukocyte synovial count; indeed, RA patients with SA have a leukocyte count in synovial fluid (SF) lower than patients with SA without underlying rheumatic diseases. The diagnosis of SA in RA patients can be difficult because the development of a hot painful joint is often confused with a relapse of the underlying joint disease leading to delay in diagnosis. For this reason the microscopic analysis and culture of synovial fluid are crucial to exclude septic arthritis.
Favero
M
M
Division of Rheumatology, Department of Clinical and Experimental Medicine, University of Padova, Italy. marta.favero@unipd.it
Schiavon
F
F
Riato
L
L
Carraro
V
V
Punzi
L
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001170:Arthritis, Infectious / Q000188:drug therapy / Q000453:epidemiology*; D001172:Arthritis, Rheumatoid / Q000276:immunology; D015984:Causality; D005260:Female; D006801:Humans; D007110:Immunity, Active / Q000187:drug effects*; D007165:Immunosuppression Therapy; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013582:Synovial Fluid / Q000166:cytology* / Q000187:drug effects
D018501:Antirheumatic Agents