Background/Purpose: Echocardiogram is frequently performed on patients presenting with septic arthritis (SA) but rarely demonstrates evidence of infective endocarditis (IE). Similarly, while patients with IE often develop musculoskeletal manifestations (including arthralgias, myalgias, and osteomyelitis) concomitant SA and IE is uncommon. The prevalence and presenting features of IE among patients with SA have not been well-defined. The purpose of this study is to describe the utilization of echocardiogram and clinical features and outcomes of patients with SA found to have endocarditis.

Methods: We conducted a retrospective cohort study of patients 18 years and older admitted to a single tertiary care center from 1998 to 2015 with septic arthritis. Baseline characteristics, clinical features, microbial profiles, rates of operative intervention, length of hospital stays (LOS), and 60-day readmission rates were determined. Patients were stratified on the basis of whether echocardiogram was performed and whether it demonstrated evidence of IE.

Results: Of 750 patients with SA, transthoracic echocardiogram (TTE) or transesophageal echocardiogram (TEE) was performed in 293 patients (39%) and found to be positive in 16 patients (2%). TTE and TEE were obtained more often in older patients (mean age 60.4 versus 56.6; p = 0.004) with higher peripheral white blood cell (WBC) counts (12.8 versus 10.6; p <0.0001) and synovial fluid WBC counts (106.8 versus 70.6; p = 0.003 (Table1). TTE and TEE were more frequently performed for those with longer LOS (13.7 versus 7.4 days; p <0.0001) who underwent operative intervention (p = 0.05), were discharged to rehabilitation (p <0.001), and died within 30 days post-discharge (p < 0.001). Presenting features, comorbidities, and outcomes did not differ significantly between those with and without IE. Echocardiograms were more frequently positive in those with SA transferred from outside hospitals as compared to those who were not (68.75% versus 31.25%; p = 0.002). Methicillin sensitive Staph aureus (MSSA) was the most bacterial cause of SA with associated endocarditis.

Conclusion:  In this study of SA, we were unable to identify clinical features and outcomes that distinguished those with or without IE other than higher rates of MSSA infection and preceding outside hospital transfers. Echocardiograms were more frequently obtained in sicker patients as implied by their presentation and eventual outcomes; however, IE was not more frequently identified in such patients. Additional study is needed to determine which factors may predict the presence of IE in patients with SA and which may benefit most from echocardiography.

« Back to 2016 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/infective-endocarditis-with-septic-arthritis-a-single-center-experience/