Thorac Cardiovasc Surg 2020; 68(S 01): S1-S72
DOI: 10.1055/s-0040-1705416
Oral Presentations
Tuesday, March 3rd, 2020
Heart Valve Disease
Georg Thieme Verlag KG Stuttgart · New York

New Perspectives of PVE Diagnostics: Impact of FISH/PCR

M. Hajduczenia
1   Berlin, Germany
,
J. Kikhney
1   Berlin, Germany
,
A. Wießner
1   Berlin, Germany
,
A. Moter
1   Berlin, Germany
,
H. Grubitzsch
1   Berlin, Germany
› Author Affiliations
Further Information

Publication History

Publication Date:
13 February 2020 (online)

Objectives: In prosthetic valve endocarditis (PVE), correct identification of the causative microorganisms is critical for diagnosis and optimal therapy. However, in numerous cases this remains challenging, in particular judging the relevance of skin flora as contaminant or infectious agent. Our objective was to detect, visualize and identify the causative microorganisms in PVE using the molecular imaging technique fluorescence in situ hybridization (FISH) combined with 16S rRNA-gene PCR and sequencing.

Methods: Patients who underwent cardiac surgery due to suspected PVE at Charité—University Medicine Berlin were included over a 10-year period. Our study comprised 113 prosthetic valves. Each valve was routinely examined by FISH combined with 16S rRNA-gene PCR and sequencing. We compared classical microbiological culture outcomes (blood and valve cultures) with FISH/PCR results and evaluated the diagnostic impact of the molecular imaging technique.

Results: Using FISH, we visualized microorganisms in PVE sections ranging from single bacterial cells to highly organized biofilms. Out of the culture-negative PVE cases, FISH/PCR succeeded to identify the causative pathogen in 35%. Overall, FISH/PCR improved the conventional cultural diagnostic methods in PVE in one-third of the cases and raised diagnostic accuracy.

Conclusion: FISH/PCR improves PVE diagnostics, complementing the conventional cultural methods. In addition to species identification, FISH provides information about the severity of PVE and state of the pathogens, e.g., stage of biofilm formation, activity, and localization on and in the prosthetic material.