Immunization with truncated recombinant protein SpaC of Erysipelothrix rhusiopathiae strain 715 serovar 18 confers protective immunity against challenge with various serovars.
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Histologic and bacteriologic findings in valvular endocarditis of slaughter-age pigs.
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Endocarditis lesions from 117 slaughter pigs were examined pathologically and etiologically in addition to 90 control hearts with cardiac valves. Lesions were located on the valves; however, the lesions had extended to the walls in 21 cases (18%). Lesions predominated on the mitral valve (59%). A total of 28 cases, from which no growth was obtained or a contamination flora was grown, were screened by fluorescence in situ hybridization (FISH) for bacteria (general bacterial probe) and probes specific for Streptococcus suis and Erysipelothrix rhusiopathiae, respectively. Using FISH, an additional 10 cases of endocarditis due to S. suis and E. rhusiopathiae were disclosed. Within lesions, streptococci predominated (53%) followed by E. rhusiopathiae (30%). Distinct features of both the lesions and the shape and localization of bacterial colonies were related to streptococci and E. rhusiopathiae. The propensity for streptococci to be localized on more than 1 valve in single hearts may be because S. suis-infected pigs tend to have been infected for a longer period compared with E. rhusiopathiae. Mineralization of endocarditis lesions was significantly associated with infection by streptococci, and was seen in 71% of the cases, whereas it was present in only 28% of lesions caused by E. rhusiopathiae. In addition, areas with mineralization were significantly correlated to the presence of a granulomatous reaction. Granulomatous endocarditis is likely a result of a foreign body reaction due to dystrophic mineralization. Local proliferation of valvular endothelial cells, found in 9 hearts in the current study, may increase the risk of developing thrombosing endocarditis in pigs. (+info)
Erysipelothrix spp. genotypes, serotypes, and surface protective antigen types associated with abattoir condemnations.
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The objective of the current study was to investigate characteristics of Erysipelothrix spp. from slaughter condemnations. Specimens from 70 carcasses with lesions suspect for swine erysipelas were collected at an abattoir in Iowa from October 2007 to February 2009. Erysipelothrix spp. were isolated from 59 of 70 carcasses (84.3%). Abattoir inspectors classified lesions as acute, subacute, or chronic; 8 of 8 (100%) were acute cases, 31 of 32 (96.9%) were subacute cases, and 20 of 30 (66.6%) were chronic cases that were isolation positive. The following serotypes were identified: 1a (40.7%; 24/59), 2 (49.2%; 29/59), 7 (1/59), 10 (1/59), 11 (1/59), and untypeable (5.1%; 3/59). Serotypes 1a and 2 were identified in pigs with acute, subacute, or chronic clinical manifestations, whereas serotypes 7, 10, and 11 were only present in chronic cases. Fifty-seven of the 59 isolates were determined to belong to E. rhusiopathiae, and 2 of 59 of the isolates were determined to be E. tonsillarum by multiplex real-time polymerase chain reaction. Surface protective antigen (spa) A was detected in all E. rhusiopathiae isolates but not in E. tonsillarum serotypes 7 and 10. The results of the present study indicate that E. rhusiopathiae serotypes 1a and 2 continue to be commonly isolated from condemned pig carcasses and that spaA is the exclusive spa type in U.S. abattoir isolates. Interestingly, E. tonsillarum, thought to be avirulent for swine, was isolated from systemic sites from 3.4% of the carcasses that were negative for E. rhusiopathiae, indicating the potential importance of this genotype in erysipelas pathogenesis. (+info)
Resistance to vancomycin and teicoplanin: an emerging clinical problem.
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Vancomycin and teicoplanin are glycopeptides active against a wide range of gram-positive bacteria. For 30 years following the discovery of vancomycin in 1956, vancomycin resistance was not detected among normally susceptible bacteria recovered from human specimens. Since 1986, however, bacteria resistant to vancomycin or teicoplanin or both have been described. Strains of the genera Leuconostoc, Lactobacillus, Pediococcus, and Erysipelothrix seem inherently resistant to glycopeptides. Species and strains of enterococci and coagulase-negative staphylococci appear to have acquired or developed resistance. There are at least two categories of glycopeptide resistance among enterococci, characterized by either high-level resistance to vancomycin (MIC, greater than or equal to 64 mg/liter) and teicoplanin (MIC, greater than or equal to 8 mg/liter) or lower-level vancomycin resistance (MIC, 32 to 64 mg/liter) and teicoplanin susceptibility (MIC, less than or equal to 1 mg/liter). The two categories appear to have similar resistance mechanisms, although genetic and biochemical studies indicate that they have arisen independently. Among coagulase-negative staphylococci, strains for which vancomycin MICs are up to 20 mg/liter or teicoplanin MICs are 16 to 32 mg/liter have been reported, but cross-resistance between these glycopeptides varies. The selective advantage accorded to glycopeptide-resistant bacteria and the observation that high-level resistance in enterococci is transferable suggest that such resistance may be expected to increase in incidence. Clinicians and microbiologists need to be aware of this emerging problem. (+info)
The genome of Erysipelothrix rhusiopathiae, the causative agent of swine erysipelas, reveals new insights into the evolution of firmicutes and the organism's intracellular adaptations.
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Serological and pathogenic characterization of Erysipelothrix rhusiopathiae isolates from two human cases of endocarditis in Japan.
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We characterized the serological and pathogenic properties of two Erysipelothrix rhusiopathiae isolates from human cases of infective endocarditis in Japan. One isolate was recovered from a fisherman, and was identified as serovar 3, which is known to be prevalent among fish isolates. This strain exhibited high virulence in mice but was avirulent in swine. Another was untypable, and avirulent in both mice and swine. Our results suggest that various serological and athogenical types of E. rhusiopathiae can induce human endocarditis. This is the first report to characterize the pathogenicity of E. rhusiopathiae isolates from human endocarditis. (+info)
Mechanism of plasma clotting by Erysipelothrix rhusiopathiae.
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Experiments were performed to determine the mechanism by which Erysipelothrix rhusiopathiae clots plasma. Detection of plasma-clotting activity in four strains of E. rhusiopathiae was carried out by mixing a 24-h broth culture of a tested bacterial strain with rabbit plasma (tube coagulation test). Sodium citrate, sodium oxalate, EDTA, and heparin were used as anticoagulants in preparing the rabbit plasma. E. rhusiopathiae strains clotted solely citrated plasma in 18 to 24 h. A known coagulase-positive strain of Staphylococcus aureus clotted all of the plasma preparations within 1 h. Various constituents of the organisms, such as cell-free culture filtrates, sonicated extracts, and Formalin-killed bacteria, were also checked for their ability to clot citrated plasma. No constituents of any strain of E. rhusiopathiae clotted the plasma. Only culture filtrates of S. aureus clotted the plasma under these conditions. The spectrophotometric assay demonstrated that two plasma-clotting strains of E. rhusiopathiae consumed the citrate in the plasma just before clotting. Of 301 veterinary clinical isolates of E. rhusiopathiae, 267 (88.7%) were positive in the tube coagulation test. On the basis of these results, it was concluded that plasma clotting by E. rhusiopathiae was due not to extracellular factors such as staphylocoagulase but to consumption of the citrate in the plasma. (+info)