TABLE 5.
Abilities of E. faecalis variants to cause endocarditis in an experimental rabbit modela
| Test organism (phenotype) | No. of animals with vegetations/no. evaluated (P)b | Quality of vegetations | Other tissue(s) affected |
|---|---|---|---|
| INY3000(pWM401) (AS− EBS−) | 0/4c | None | None |
| OG1SSp)pWM401) (AS− EBS+) | 4/4 (0.014) | Very small (1+) | Spleen enlargement |
| INY3000(pINY1801) (AS+ EBS−) | 4/4 (0.014) | Very small (1+) | Spleen enlargement |
| OG1SSp(pINY1801) (AS+ EBS+) | 4/4c (0.014) | Large (3+) | Spleen enlargement, lung congestion |
New Zealand White rabbits (4 to 6 kg) underwent transaortic catheterization for 2 h and were injected intravenously through their marginal ear veins with approximately 2 × 109 CFU. Animals were sacrificed on day 3 and examined for heart vegetations and signs of infection in other tissues.
P values were determined by Fisher’s exact probability test in comparison to the number of animals with vegetations in the AS− EBS− group.
Two additional animals were injected with 5 × 109 CFU. Neither of the two animals given INY3000(pWM401) succumbed or showed vegetations in the heart. Both animals given OG1SSp(pINY1801) succumbed overnight and showed extensive lung necrosis.