Prosthetic Aortic Valve Endocarditis.

An 89-year-old woman who had received aortic valve replacement and pacemaker implantation 3 years before admission was hospitalized with a low-grade fever. Blood cultures repeatedly detected Enterobacter cloacae, and transesophageal echocardiography (TEE) revealed periannular wall thickening that could not be confirmed to be a periannular abscess. Gallium single-photon emission computed tomography (SPECT) scintigraphy to confirm the diagnosis revealed increased activity as a red spot around the posterior side of the prosthetic aortic annulus, next to the thickened atrial wall noted on TEE (Picture; A: axial view, B: coronal view). Follow-up of TEE revealed a thinning lesion at the periannular wall after two-week treatment of intravenous cefepime and ciprofloxacin. Gallium SPECT scintigraphy was a useful noninvasive modality in this case, as it is difficult to diagnose prosthetic valve endocarditis caused by non-HACEK Gram-negative bacillus because of its rareness as a pathogen (1) and the low sensitivity of modified Duke's criteria for prosthetic valve endocarditis due to an impaired image quality by artifacts or acoustic shadow with implanted cardiac devices (2).

Picture.

The authors state that they have no Conflict of Interest (COI).