Background: Sonication is a promising tool for microbiological diagnosis of device infection and colonization. We assessed the role of sonication of different device’s components explanted from patients with cardiac device infections (CDI). Methods: A total of 90 devices were collected (31 generators and 59 electrodes) from 31 subjects with CDI. Devices were inoculated in TSB for 24 h and cultured with traditional methods. They were also vortexed for 30 s and then sonicated for 5 min at a frequency >20kHz using the BactoSonic (BANDELIN electronic GmbH & Co. KG, Germany). The cell count of collected sample was performed. Results: Sonication yielded bacteria in 63/90 (70%) devices compared with only 52/90 (57%) of traditional culture (p=0.002). The concordance between the two methods was 88%. A total of 11 strains were only detected in sonication fluid culture: 7 S. epidermidis, 1 S. hominis, 2 C. striatum, 1 Brevundimonas spp. Among generators, 27/31 (87%) grew bacteria with sonication and 26/31 (83%) without sonication (p=0.9); instead, 36/52 (69%) and 26/52 (50%) electrodes were positive with and without sonication, respectivel (p=0.004). The bacterial cell count in sonication fluid was higher than in traditional culture (34.5x10*4 vs 16.9x10*4 CFU/ml, p=0.019). However, the difference was only significant for electrodes (25x10*4 vs 12x10*4 CFU/ml, p=0.007) rather than for generators (45x10*4 vs 21x10*4 CFU/ml, p=0.29). When we stratified patients according to the bacterial amount detected by standard culture, we found that the difference between the two methods was more evident for CFU/ml less than 10*3 (p=0.001). Conclusions: Sonication of explanted cardiac devices was highly sensitive for pathogen recovery in electrodes rather than in generators. The use of sonication before culture may be critical to improve bacterial detection especially in those surfaces where the production of biofilm is high, such as electrodes.
Sonication of Cardiac Devices and their Components: Microbiological and Pathogenetic Implication in Cardiac Device Infections” / Oliva, Alessandra; Nguyen, BICH LIEN; Mascellino, Maria Teresa; Iannetta, Marco; D'Abramo, Alessandra; Cipolla, Alessia; V., Malagnino; Ciccaglioni, Antonio; Vullo, Vincenzo; Mastroianni, Claudio Maria. - STAMPA. - (2012). (Intervento presentato al convegno IASM-ICAAC 2012 tenutosi a San Francisco USA nel 9-12 Settembre 2012).
Sonication of Cardiac Devices and their Components: Microbiological and Pathogenetic Implication in Cardiac Device Infections”
OLIVA, ALESSANDRA;NGUYEN, BICH LIEN;MASCELLINO, Maria Teresa;IANNETTA, MARCO;D'ABRAMO, ALESSANDRA;CIPOLLA, ALESSIA;CICCAGLIONI, Antonio;VULLO, Vincenzo;MASTROIANNI, Claudio Maria
2012
Abstract
Background: Sonication is a promising tool for microbiological diagnosis of device infection and colonization. We assessed the role of sonication of different device’s components explanted from patients with cardiac device infections (CDI). Methods: A total of 90 devices were collected (31 generators and 59 electrodes) from 31 subjects with CDI. Devices were inoculated in TSB for 24 h and cultured with traditional methods. They were also vortexed for 30 s and then sonicated for 5 min at a frequency >20kHz using the BactoSonic (BANDELIN electronic GmbH & Co. KG, Germany). The cell count of collected sample was performed. Results: Sonication yielded bacteria in 63/90 (70%) devices compared with only 52/90 (57%) of traditional culture (p=0.002). The concordance between the two methods was 88%. A total of 11 strains were only detected in sonication fluid culture: 7 S. epidermidis, 1 S. hominis, 2 C. striatum, 1 Brevundimonas spp. Among generators, 27/31 (87%) grew bacteria with sonication and 26/31 (83%) without sonication (p=0.9); instead, 36/52 (69%) and 26/52 (50%) electrodes were positive with and without sonication, respectivel (p=0.004). The bacterial cell count in sonication fluid was higher than in traditional culture (34.5x10*4 vs 16.9x10*4 CFU/ml, p=0.019). However, the difference was only significant for electrodes (25x10*4 vs 12x10*4 CFU/ml, p=0.007) rather than for generators (45x10*4 vs 21x10*4 CFU/ml, p=0.29). When we stratified patients according to the bacterial amount detected by standard culture, we found that the difference between the two methods was more evident for CFU/ml less than 10*3 (p=0.001). Conclusions: Sonication of explanted cardiac devices was highly sensitive for pathogen recovery in electrodes rather than in generators. The use of sonication before culture may be critical to improve bacterial detection especially in those surfaces where the production of biofilm is high, such as electrodes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
