253 - Is Echocardiogram always indicated in Bacteremia?

Background: Echocardiography (ECHO) is a commonly used test; and is part of the Duke’s criteria for diagnosing endocarditis (IE). Our objectives were to analyze utilization and results of ECHO in pts with bacteremia growing organisms not typically associated with IE, and to evaluate whether ECHO contributed to a diagnosis of IE.

Methods: A retrospective review in a 680-bed tertiary care hospital from 2013-2019. Adult pts with bacteremia with at least 2 positive blood cultures for an organism not typically associated with IE such as Streptococcus viridans, Staphylococcus spp. and enterococcus, and who underwent ECHO were included. Data was collected on demographics, blood cultures, timing of ECHO and its’ findings. Modified Duke’s criteria was used to diagnose IE.

Results: Ninety four pts were included. Mean age 62 yrs. (range 23-91yrs). 50 (53%) were men. DM noted in 49(52%), CAD in 37(39%), CHF in 54 (57%), chronic kidney disease in 22(23%), hemodialysis in 19(20%), history of IE in 9 (10%). Transthoracic ECHO in 34 (36%), transesophageal ECHO in 28(30%), 32(34%) had both.  Identifiable sources of bacteremia were urinary tract infection in 9 (10%), pneumonia 5 (5%), PICC line 5 (5%), wound/tissue infection 3 (3%).Clinicians did not specify the indication for ECHO in any of the cases.  Unidentified source of bacteremia noted in 72(77%). Bacteremia was community acquired in 70(74%).  Mean days of positive blood cultures 5.6 days (range 1-34 days).  Gram (-) organism isolated in 44(47%), Gram (+) in 50(53%), of these, 50 (54%) had an implanted devices/indwelling catheter: 39 cardiac implantable device, 12 indwelling/tunneled catheter. The overall yield of ECHO in bacteremia was 11/94 (12%).  ECHO in Gram (-) bacteremia had yield of 9% (4/44 pts) of them only 1 met possible IE by Duke’s criteria. Gram (+) bacteremia had an ECHO yield of 14% (7/50pts); of them 4 met possible IE Duke’s criteria. None of the cases met definite criteria for IE.

Conclusion: Yield of ECHO for the diagnosis of IE in pts with bacteremia with organisms other than Streptococcus viridans, staphylococci or enterococci was low even in the presence of implanted devices or indwelling catheters. Better criteria for ECHO utilization will reduce its use and potentially increase its yield.