Septic arthritis of the knee: clinical and laboratory comparison of groups with different etiologies

Abstract

OBJECTIVES:To clinically and epidemiologically characterize a population diagnosed with and treated for septic arthritis of the knee, to evaluate the treatment results and to analyze the differences between patients with positive and negative culture results, patients with Gram-positive and Gram-negative bacterial isolates and patients with S. aureus- and non-S. aureus-related infections.METHODS:One hundred and five patients with septic knee arthritis were included in this study. The clinical and epidemiological data were evaluated. Statistical analysis was performed to compare patients with and without an isolated causative agent, patients with Gram-positive and Gram-negative pathogens and patients with S. aureus-related and non S. aureus-related infections.RESULTS:Causative agents were isolated in 81 patients. Gram-positive bacteria were isolated in 65 patients and Gram-negative bacteria were isolated in 16 patients. The most commonly isolated bacterium was S. aureus. Comparing cases with an isolated pathogen to cases without an isolated pathogen, no differences between the studied variables were found except for the longer hospital stays of patients in whom an etiological agent was identified. When comparing Gram-positive bacteria with Gram-negative bacteria, patients with Gram-positive-related infections exhibited higher leukocyte counts. Patients with S. aureus-related infections were more frequently associated with healthcare-related environmental encounters.CONCLUSION:S. aureus is the most common pathogen of septic knee arthritis. Major differences were not observed between infections with isolated and non-isolated pathogens and between infections with Gram-positive and Gram-negative bacteria. S. aureus infections were more likely to be associated with a prior healthcare environment exposure.

Knee septic arthritis caused by α-hemolytic Streptococcus in a patient with a recent history of knee arthroscopy: a case report

“…Notably, α-hemolytic streptococci are a large group of bacteria that are members of the oral commensal flora; however, in some cases, they can colonize distant organs (for example, in patients with diseases such as endocarditis [S. viridans]) [25]. To our knowledge, no report has described post-arthroscopic septic arthritis of the knee caused by α-hemolytc streptococci, although staphylococcal joint infections are widely reported in the available literature [26][27][28]. We conclude that septic arthritis of the knee could be secondary to transient α-hemolytic streptococcal bacteremia following seeding of oral flora at a site of recent surgery where necrotic tissue favors bacterial growth.…”

Mini open surgical treatment of knee septic arthritis with local anesthesia: a prospective preliminary report

“…The knee joint is the most common site of septic arthritis [15]. Joint contamination is usually the result of hematogenous bacterial infection, and similarly, it can also occur following surgery, joint injection or trauma [16][17][18].…”

Exposure to fermentation supernatant of Staphylococcus aureus accelerated dedifferentiation of chondrocytes and production of antimicrobial peptides

“…Despite treatments of septic arthritis including drainage, antibiotic therapy, and hospital care have been improved greatly, irreversible destruction of joint is reported to maintained as high as in 50% of bacteria infected joints . As revealed by clinical epidemiology, the majority of septic arthritis patients were infected by Gram‐positive bacteria and the most common bacterium isolated was S. aureus . While, Gram‐negative bacterial infections accounts approximately for 20% of septic arthritis reported by Eberst‐Ledoux et al…”