Infection of Cardiovascular Implantable Electronic Devices: Detection with Sonication, Swab Cultures, and Blood Cultures

BACKGROUND: The number of patients with cardiovascular implantable electronic devices (CIEDs) is increasing. The purpose of this study was to compare three methods (sonication, swab cultures, and blood cultures) to detect bacteria in infections of CIEDs. METHODS: Patients with pocket infection of CIEDs and/or CIED-associated infective endocarditis were prospectively included. Generators and leads were sonicated together. Swab cultures of the generator pocket and blood cultures were performed. RESULTS: Between January 2009 and September 2012, 18 patients with a CIED infection were recorded, including two definite and four possible CIED-IEs. In 17 patients, blood cultures were performed and the device was analyzed by sonication. A swab culture from the device pocket was performed in 16 cases. Ten (59%) patients received antibiotic therapy before the device was removed. In 15 of 16 cases (94%), bacteria were detected by sonication, while bacteria were detected in only nine (56%) and seven (41%) cases by swab-and blood cultures, respectively. In four cases (24%), sonication was the only method that detected bacteria. The following bacteria were detected by sonication: methicillin-sensitive Staphylococcus aureus (MSSA; n = 6), coagulase-negative staphylococci (CNS; n = 3), Propionibacterium acnes (n = 2), Staphylococcus lugdunensis (n = 1), MSSA/Pseudomonas aeruginosa (n = 1),Bacillus cereus (n = 1), MSSA/P. acnes (n = 1), andP. acnes/CNS (n = 1). All positive swab cultures and all positive blood cultures but one grew the same bacteria as sonication fluid cultures. CONCLUSION: Sonication can be more sensitive than swab cultures or blood cultures in detecting bacteria in infections of CIEDs.