Staphylococcus aureus native arthritis over 10 years.
OBJECTIVES
Septic arthritis is associated with significant case fatality and morbidity. Staphylococcus aureus is the most common cause of arthritis. We aimed to analyze the microbiological features of S. aureus causing native arthritis and to investigate their influence on the clinical outcome of the infection.


PATIENTS AND METHODS
We conducted a retrospective study including all episodes of S. aureus native arthritis between 2005-2015. Phenotypic (antimicrobial susceptibility, β-hemolysis, agr functionality, biofilm formation) and genotypic characteristics (pulsed-field gel electrophoresis, DNA microarrays) were investigated. The primary endpoint was microbiological failure of treatment, including infection relapse, persistence, or attributable death.


RESULTS
Twenty-nine patients were included (65.5% of men, mean age: 59): seven (24.1%) patients presenting with methicillin-resistant S. aureus (MRSA) native arthritis and 19 with methicillin-susceptible S. aureus (MSSA) native arthritis. Treatment failure occurred in seven (26.9%) patients (4/7 patients [57.1%] among MRSA infections vs. 3/19 [15.8%] among MSSA infections). The persistence rate was similar in MRSA and MSSA infections (1/7 vs. 3/19). However, the case fatality was significantly higher in patients with MRSA infection (3/7 vs. 0/19). The most frequent clonal complex (CC) was CC5 (38.1%). MSSA showed higher genetic variability (nine CCs) versus MRSA (3 CCs).


CONCLUSIONS
Beyond methicillin resistance, we did not find phenotypic or genotypic factors associated with the poor outcome of S. aureus native arthritis. CC5 was the major CC, showing the higher genetic variability of MSSA versus MRSA.
['Muñoz-Gallego|I|I|', 'Mancheño|M|M|', 'Pérez-Montarelo|D|D|', 'Viedma|E|E|', 'Chaves|F|F|', 'Lora-Tamayo|J|J|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D000900:Anti-Bacterial Agents D001170:Arthritis, Infectious D003131:Combined Modality Therapy D015897:Comorbidity D004322:Drainage D004352:Drug Resistance, Microbial D005260:Female D006785:Hospitals, University D006801:Humans D008297:Male D055624:Methicillin-Resistant Staphylococcus aureus D008875:Middle Aged D012008:Recurrence D012189:Retrospective Studies D013030:Spain D013203:Staphylococcal Infections D013211:Staphylococcus aureus D017211:Treatment Failure D014774:Virulence
Staphylococcus aureus MRSA Arthrite septique native Infections des articulations Joint infections Molecular epidemiology Native septic arthritis SARM Épidémiologie moléculaire