Week of 10 November 2020

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These bioprosthetic aortic valve leaflets are infected!

Bacterial endocarditis is a known potential complication of the implantation of a bioprosthetic cardiac valve. This can result from a break in sterility or simply following an episode of sporadic bacteremia in the patient. The bioprosthetic leaflet (L) is thickened by large amounts of fibrin deposits (F) admixed with red blood cells, leukocytes and sometimes mineral deposits as well as colonies of bacteria (*). These are difficult to treat as bacteria are protected from antibiotics in these locations due to their lack of blood supply, and may form biofilms.

1. HE&S, original magnification: x0.6, scale bar: 1 mm.
2. HE&S, original magnification: x10, scale bar: 100 µm.
3. Gram staining, original magnification: x40, scale bar: 25 µm.
*: Colonies of bacteria; L: Bioprosthetic leaflet; F: Fibrin deposits admixed with red blood cells, leukocytes and mineral deposits.

This histopathology image is one example from the comprehensive suite of Pathology Services offered by IMMR’s in-house team of Board-certified Veterinary Pathologists.

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