Fatal Bioprosthetic Aortic Valve Endocarditis Due to Cardiobacterium valvarum

Abstract

Cardiobacterium valvarum was isolated from the blood of a 71-year-old man with fatal aortic valve endocarditis. The API NH system was used for phenotypic characterization of the C. valvarum strain. This is the first case of infective endocarditis caused by C. valvarum in Germany and the first case worldwide affecting a prosthetic valve and lacking an obvious dental focus. CASE REPORTA 71-year-old patient was admitted to our cardiac department due to complicated severe endocarditis. His medical history revealed surgery 2 years previously with insertion of bypasses and replacement of a stenotic aortic valve with a bioprosthesis. No infective endocarditis was diagnosed at that time. Two months prior to admission, he had suffered backache resulting from a disc prolapse, which was conservatively treated with repeated local injections of nonsteroidal antiinflammatory drugs. In the last weeks before admission, he developed a general weakness accompanied by fever, chills, edema and petechiae in the legs, and psychomotoric slowing. Upon admission to a nearby hospital (day 1), arterial hypotension was treated with noradrenalin. Transesophageal echocardiography revealed endocarditis with vegetations on the bioprosthetic aortic valve. Blood cultures were taken immediately and showed growth of fastidious gram-negative rods after 4 days of incubation. In response to this finding, empirical antibiotic therapy was adjusted to ceftriaxone, rifampin, and amikacin. When an atrioventricular block, grade III, appeared on day 6, the patient was transferred in stable cardiorespiratory condition to the intensive care unit of our department of cardiology. Laboratory tests showed anemia (hemoglobin, 9.6 g/dl), increased concentration of C-reactive protein (107 mg/ liter), leukocytosis (16,900 leukocytes/l), and a reduced platelet count (74,000 cells/l). Blood cultures taken at that time were incubated for 3 weeks but remained negative. For a more detailed assessment, transesophageal echocardiography was repeated; it showed a large floating vegetation on a degenerated, insufficient aortic valve and a hypodense region extending to the aortic bulbus suspicious of a large perivalvular abscess cavity. In the cerebellum, two new ischemic areas, indicative of septic embolism, were identified by cranial computerized tomography and magnetic resonance tomography. No indications of further embolisms were found in the spleen, liver, kidneys, or eyes upon sonographic and ophthalmoscopic examinations. Magnetic resonance tomography of the lumbar spine was suspicious of erosive osteochondrosis (L3/4) and spondylodiscitis, presumably resulting from nonsteroidal antiinflammatory drug injections.On day 9, the patient was transferred to our center for cardiac surgery for a high-risk prosthetic valve replacement. Intraoperatively, the aortic valve prosthesis showed massive inflammatory destruction and a large abscess near the anulus, including nearly the complete circumference of the aortic bulbus. Although it was impossible to remove all of the inflamed tis...

A case of Cardiobacterium valvarum endocarditis with cerebral hemorrhage after MVR, TVP and vegetation removal operation

“…NR_025934.1), finally identified as the former. We speculate there may be mutation of the strain in our case, so the homology was not as high as the previous cases, major of which were higher than 99% [ 1 – 4 , 6 , 7 , 18 , 20 ].…”

“…Notably, an abrupt cerebral hemorrhage with herniation occurred in this case, and an intravascular thrombus was found in the right temporal lobe, never reported before. Other neurological complications were common in the previous cases including cerebral infarction [ 1 , 4 , 6 ], subarachnoid hemorrhage [ 4 , 7 , 9 ], cerebral vasculitis [ 1 ] and cerebral embolization [ 2 ]. Neurological sequelae may be another clinical feature of C. valvarum bacteria.…”

Aortic vascular graft infection caused by Cardiobacterium valvarum: A case report

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Novel diversity of bacterial communities associated with bottlenose dolphin upper respiratory tracts

“…, 2009). We also observed several sequences (3.6% of total sequences) that showed greatest sequence homology with Cardiobacterium valvarum , an organism associated with fatal endocarditis in humans (Geißdörfer et al. , 2007), and Suttonella ornithocola , a bacterium isolated from the congested lungs of dead blue tits ( Cyanistes caeruleus ) (Foster et al.…”