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We investigated the importance of enterococcal aggregation substance (AS) and enterococcal binding substance (EBS) in rabbit models of Enterococcus faecalis cardiac infections. First, American Dutch belted rabbits were injected intraventricularly with 108 CFU and observed for 2 days. No clinical signs of illness developed in animals given AS− EBS−organisms, and all survived. All rabbits given AS−EBS+ organisms developed signs of illness, including significant pericardial inflammation, but only one of six died. All animals given AS+ EBS− organisms developed signs of illness, including pericardial inflammation, and survived. All rabbits given AS+ EBS+ organisms developed signs of illness and died. None of the rabbits receiving AS+ EBS+ organisms showed gross pericardial inflammation. The lethality and lack of inflammation are consistent with the presence of a superantigen. Rabbit and human lymphocytes were highly stimulated in vitro by cell extracts, but not cell-free culture fluids, of AS+ EBS+ organisms. In contrast, cell extracts from AS− EBS− organisms weakly stimulated lymphocyte proliferation. Culture fluids from human lymphocytes stimulated with AS+/EBS+enterococci contained high levels of gamma interferon and tumor necrosis factor alpha (TNF-α) and TNF-β, which is consistent with functional stimulation of T-lymphocyte proliferation and macrophage activation. Subsequent experiments examined the abilities of the same strains to cause endocarditis in a catheterization model. New Zealand White rabbits underwent transaortic catheterization for 2 h, at which time catheters were removed and animals were injected with 2 × 109 CFU of test organisms. None of the animals given AS− EBS− organisms developed vegetations or showed autopsy evidence of tissue damage. Rabbits given AS− EBS+ or AS+ EBS−organisms developed small vegetations and had splenomegaly at autopsy. All rabbits given AS+ EBS+ organisms developed large vegetations and had splenomegaly and lung congestion at autopsy. Similar experiments that left catheters in place for 3 days revealed that all rabbits given AS− EBS− or AS+ EBS+ organisms developed vegetations, but animals given AS+ EBS+ organisms had larger vegetations and autopsy evidence of lung congestion. These experiments provide direct evidence that these two cell wall components play an important role in the pathogenesis of endocarditis as well as in conjugative plasmid transfer.

The group G streptococcus (GGS) is a rare cause of deep soft-tissue infection. We report that we believe is the first case of acute diffuse GGS myositis in association with toxic shock. Although the causative organism did not contain the genes for group A streptococcal pyrogenic exotoxins (SPEs) or make SPEs, the organism produced at least one new toxin that shared the biologic properties of the SPEs.

The incidence of infectious diseases in the United States has been increasing since 1980. Re-emergent conditions, multidrug-resistant bacteria, newly identified infections, and bioterrorism have prompted public health surveillance and control initiatives, including the use of telehealth technology. Infectious diseases, such as West Nile Virus, pose a particular threat to rural areas, where access to infectious disease specialists (IDS) is limited. Initial, in-patient IDS consultations are reimbursed by Centers for Medicare & Medicaid Services for in-person and for telehealth services. Follow-up consultation and subsequent care visits are reimbursed when delivered via in-person care, but not reimbursed when delivered via telehealth. The purpose of this study is to investigate the efficacy of telehealth technology (interactive videoconferencing) in providing timely, efficient, and prudent infectious disease care for rural patients. We conducted a retrospective, comparative review of medical records (n = 107) from inpatients at a metropolitan hospital (n = 59) in a rural state who received in-person IDS treatment, with records from inpatients at nonmetropolitan, rural, and frontier hospitals (n = 48) in the same state who received telehealth IDS treatment. Outcome measures, including number of days hospitalized, number of days receiving intravenous antibiotic, survival, and transfer to another hospital, were compared for three commonly occurring infectious diseases: neutropenic fever, bacterial pneumonia, or bacterial wound infection. Patients treated via telehealth had fewer days on antibiotics and fewer days hospitalized than patients treated via in-person intervention. Survival rates did not differ significantly between groups, but were lower for telehealth patients. Fewer in-person patients required transfer to hospitals offering a higher level of care. Ninety percent of telehealth patients were able to remain at their local hospital for treatment. Results were statistically significant only for selected outcomes and conditions. IDS treatment for the conditions studied is equally effective when delivered via telehealth as when delivered via in-person methods.