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Biomedical subjects

James M Steckelberg

Publications and source records attributed to James M Steckelberg.

At least 19 recordsLinked to original sources

Frequency of permanent pacemaker or implantable cardioverter-defibrillator infection in patients with gram-negative bacteremia.

BACKGROUND: Despite the frequent occurrence of bacteremia due to gram-negative organisms in patients with underlying permanent pacemakers (PPMs) or implantable cardioverter defibrillators (ICDs), the outcome and treatment of these patients has received scant attention. In patients with PPMs or ICDs who have Staphylococcus aureus bacteremia, 45% have PPM/ICD infection. METHODS: We conducted a retrospective cohort study over a 7-year period to assess the clinical features and frequency of PPM/ICD infection in patients with gram-negative bacteremia, as well as the incidence of relapse in patients for whom the device was not removed. RESULTS: Forty-nine patients were included in the study; 3 (6%) had either definite (2 patients) or possible (1 patient) PPM/ICD infection. Both patients with definite PPM/ICD infection had clear infection of the generator pocket. None of the other patients with alternate sources of bacteremia developed PPM/ICD infection. Thirty-four patients with retained PPM/ICD were observed for >12 weeks (median time, 759 days), and 2 (6%) developed relapsing bacteremia, although they each had alternative sources of relapse. CONCLUSIONS: In sharp contrast to S. aureus infection, PPM/ICD infection in patients with gram-negative bacteremia was rare, and no patients appeared to have secondary PPM/ICD infection due to hematogenous seeding of the system. Despite infrequent system removal in these patients, relapsing bacteremia among patients who survived initial bacteremia was rarely seen. If secondary PPM/ICD infection occurs in patients with gram-negative bacteremia, it is either uncommon or it is cured with antimicrobial therapy despite device retention.

Aged↗

Evaluation of caspofungin and amphotericin B deoxycholate against Candida albicans biofilms in an experimental intravascular catheter infection model.

Candida albicans biofilms complicate the treatment of infected implanted intravascular devices because of decreased antifungal susceptibility. In our investigation, 48 rabbits with experimental central venous catheter C. albicans infection were equally allocated to a control arm or to receive amphotericin B deoxycholate or caspofungin treatment while undergoing systemic and intraluminal lock therapy for 7 days. C. albicans was cultured from catheters from all control rabbits, from 3 that received amphotericin B, and from 0 that received caspofungin. Differences in colony counts were detected between the control and amphotericin (P<.001) and control and caspofungin (P<.001) arms. Caspofungin may be useful in the treatment of C. albicans biofilm-associated intravascular catheter infections, which warrants further study.

Amphotericin B↗

Do follow-up imaging examinations provide useful prognostic information in patients with spine infection?

BACKGROUND: The ability of follow-up imaging examinations to predict treatment failure in patients with spine infections has not been well studied. METHODS: We conducted a retrospective cohort analysis of patients with spine infection who had both baseline and 4-8-week follow-up imaging results available at the Mayo Clinic (Rochester, MN) during the period of 1994-2002. Follow-up imaging findings were categorized as improved, equivocal, or worse, compared with the baseline findings, on the basis of a simple grading system that focused on associated soft-tissue findings. RESULTS: Baseline and 4-8-week follow-up imaging findings were available for 79 patients with spine infection who presented to the Mayo Clinic during 1994-2002. Thirty-five infections (44%) were due to Staphylococcus aureus, 9 (11%) were due to coagulase-negative staphylococci, and 16 (20%) were culture negative. Twenty-seven (34%), 38 (48%), and 14 (18%) follow-up images were graded improved, equivocal, or worse, respectively. The cumulative rates of 1-year survival free of microbiologically confirmed treatment failure were 100%, 89% (95% CI, 74%-96%), and 56% (95% CI, 24%-83%) for patients with improved, equivocal, and worse follow-up imaging findings, respectively (P=.004). Only 3 (6%) of 52 patients deemed to have had clinical improvement at the time of the follow-up imaging study experienced treatment failure. Elevated levels of inflammatory biomarkers identified 2 of these patients as high risk for treatment failure, and the levels were not performed for the third patient. CONCLUSIONS: Applying a simple grading scale to assess follow-up imaging examinations for patients with spinal infection stratifies their risk of treatment failure. Patients' clinical statuses and inflammatory biomarker responses may be helpful for selecting patients at high risk for treatment failure who should undergo follow-up magnetic resonance imaging.

Aged↗

Ceftobiprole medocaril (BAL5788) treatment of experimental Haemophilus influenzae, Enterobacter cloacae, and Klebsiella pneumoniae murine pneumonia.

Ceftobiprole (BAL9141) is an investigational cephalosporin active against methicillin- and vancomycin-resistant staphylococci administered as a water-soluble prodrug, ceftobiprole medocaril (BAL5788). Using an immunocompetent murine pneumonia model of Haemophilus influenzae, Enterobacter cloacae, or extended-spectrum beta-lactamase (ESBL) nonproducing or producing Klebsiella pneumoniae pneumonia, we compared results of treatment with ceftobiprole medocaril (71 mg/kg, sc, qid), ceftriaxone (50 mg/kg, im, bid), or cefepime (50 mg/kg, ip, q.i.d.). Results were expressed as median and 25th to 75th percentile log10 colony forming units per gram of lung tissue. Ceftobiprole, ceftriaxone, and cefepime were each more active than was no treatment and were equally active for treatment of experimental H. influenzae, E. cloacae, or ESBL-nonproducing K. pneumoniae pneumonia. For ESBL-producing K. pneumoniae, no differences were detected between no treatment and treatment with ceftobiprole, ceftriaxone, or cefepime. Ceftobiprole is active against H. influenzae, E. cloacae, and ESBL-nonproducing K. pneumoniae in an immunocompetent experimental murine pneumonia model.

Animals↗

Lack of detection of human retrovirus-5 proviral DNA in synovial tissue and blood specimens from individuals with rheumatoid arthritis or osteoarthritis.

OBJECTIVE: Prior studies have suggested an association of human retrovirus 5 with rheumatoid arthritis. The purpose of this study was to determine if human retrovirus-5 proviral DNA is present in synovial tissue and blood specimens from patients with rheumatoid arthritis or osteoarthritis, or those without joint disease. METHODS: Synovial tissue and whole blood from 75 patients with rheumatoid arthritis, 75 patients with osteoarthritis, and 50 patients without a primary arthritis diagnosis were assayed by real-time quantitative polymerase chain reaction (PCR) using primers that amplify a 186-bp fragment of human retrovirus-5 proviral DNA. RESULTS: A total of 200 tissue specimens, 200 mononuclear cells, and 196 of 200 granulocyte specimens tested negative for human retrovirus-5 proviral DNA. No association between human retrovirus 5 and rheumatoid arthritis or osteoarthritis (P = 0.516) was identified. Granulocyte specimens from 4 patients, 2 with rheumatoid arthritis and 2 with osteoarthritis, yielded a low positive human retrovirus-5 proviral DNA signal (83-1,365 copies of human retrovirus-5 proviral DNA/ml blood). CONCLUSION: Contrary to prior reports, we did not find an association between human retrovirus 5 and rheumatoid arthritis or osteoarthritis using a real-time PCR assay. Our findings are consistent with the recent finding that human retrovirus 5 is actually rabbit endogenous retrovirus H.

Adolescent↗

Lack of association of Staphylococcus aureus type A beta-lactamase with cefazolin combined with antimicrobial spacer placement prosthetic joint infection treatment failure.

Association of cefazolin treatment failure with type A beta-lactamase-producing Staphylococcus aureus has been suggested. The prevalence of beta-lactamase gene types among 23 methicillin-susceptible S. aureus (MSSA) isolates associated with prosthetic joint infection (PJI) treated with cefazolin was determined using polymerase chain reaction (PCR), and clinical and microbiologic outcomes were assessed. PCR revealed 4 isolates without blaZ, and 12 with type A, 2 with type B, and 5 with type C blaZ. Of 13 patients undergoing resection arthroplasty with subsequent reimplantation, all received antimicrobial spacer placement at resection with or without antimicrobial-impregnated polymethylmethacrylate at reimplantation. All 13 cases had tissue cultures at time of reimplantation that were negative for S. aureus and 11 had histopathology specimens showing no acute inflammation. Of 8 type A cases undergoing reimplantation, all prostheses remained in place at follow-up (median, 798 days; range, 32-927 days). We conclude that type A blaZ is common in MSSA PJI and that cefazolin therapy for blaZ MSSA PJI can be successful when combined with 2-stage reimplantation and local antimicrobial therapy.

Anti-Bacterial Agents↗

Changing epidemiology of infective endocarditis.

Infective endocarditis (IE) continues to be a serious infection with a stable incidence rate over time and a persistently high mortality. Population-based studies from France, Netherlands, Sweden, and the United States reported on the epidemiology of this infection. These studies suggest a changing distribution of underlying valvular heart disease in patients with IE, namely a decreasing proportion of patients with rheumatic heart disease and an increasing proportion with underlying prosthetic valves or mitral valve prolapse. There is controversy regarding the change of spectrum of IE-causative organisms. In some geographically defined populations with complete case ascertainment, viridans group streptococci continue to be the most common causative organisms, whereas in passively reported community surveys and in referral-center case series, Staphylococcus aureus is surpassing streptococci as the leading cause for IE.

Journal Article↗

Medical versus surgical management of Staphylococcus aureus prosthetic valve endocarditis.

PURPOSE: The study's purpose was to identify prognostic factors associated with mortality in Staphylococcus aureus prosthetic valve endocarditis and to determine whether these factors influenced decisions to treat medically versus surgically. We also analyzed whether there was a subset of patients who were cured with medical therapy alone. SUBJECTS AND METHODS: A retrospective review of patients with S aureus prosthetic valve endocarditis was performed. Demographic and clinical data were collected from existing medical records. Severity of illness was classified using American Society of Anesthesiologists (ASA) score. Impact of treatment on in-hospital mortality was assessed using multiple logistic regression analysis. RESULTS: Fifty-five patients met the Duke criteria for definite S aureus prosthetic valve endocarditis. Twenty-three patients were treated medically, and 32 patients had surgical intervention. Overall mortality was 36% (28% in the surgical group and 48% in the medical group). ASA score IV (P < .001) and older age (P = .014) were significant risk factors of mortality. Patients with ASA score IV (P = .037) and multiple prosthetic valves (P = .013) were less likely to undergo surgery. Medically treated patients were older compared with those in the surgical group (median age 66 vs 55 years, P = .04). All 4 patients aged less than 50 years in the medically treated group survived. CONCLUSION: Mortality was generally higher in the medically treated patients with S aureus prosthetic valve endocarditis. Multivariable analysis showed that ASA class IV and bioprosthetic valves were independent predictors of mortality. A subset of medically treated patients characterized by age less than 50 years, ASA score III, and without cardiac, central nervous system, or systemic complications were cured without surgical intervention.

Aged↗

Effect of gamma irradiation on viability and DNA of Staphylococcus epidermidis and Escherichia coli.

Gamma irradiation is widely used for sterilization; however, its effect on elimination of amplifiable DNA, an issue of relevance to molecular diagnostic approaches, has not been well studied. The effect of gamma irradiation on the viability of Staphylococcus epidermidis and Escherichia coli (using quantitative cultures) and on their DNA (using quantitative 16S rRNA gene PCR) was evaluated. Viability was abrogated at 2.8 and 3.6 kGy for S. epidermidis and E. coli, respectively. The radiation dose required to reduce viable bacteria by one log10 (D10 value) was 0.31 and 0.35 kGy for S. epidermidis and E. coli, respectively. D10 values for amplifiable DNA extracted from bacteria were 2.58 and 3.09 kGy for S. epidermidis and E. coli, respectively, whereas D10 values for amplifiable DNA were significantly higher for DNA extracted from irradiated viable bacterial cells (22.9 and 52.6 kGy for S. epidermidis and E. coli, respectively; P<0.001). This study showed that gamma irradiation of DNA in viable bacterial cells has little effect on amplifiable DNA, was not able to eliminate amplifiable 16S rRNA genes at a dose of up to 12 kGy and cannot therefore be used for elimination of DNA contamination of PCR reaction components or laboratory equipment when this DNA is present in microbial cells. This finding has practical implications for those using molecular diagnostic techniques in microbiology.

Colony Count, Microbial↗

Garenoxacin treatment of experimental endocarditis caused by viridans group streptococci.

The activity of garenoxacin was compared to that of levofloxacin or penicillin in a rabbit model of Streptococcus mitis group (penicillin MIC, 0.125 microg/ml) and Streptococcus sanguinis group (penicillin MIC, 0.25 microg/ml) endocarditis. Garenoxacin and levofloxacin had MICs of 0.125 and 0.5 microg/ml, respectively, for both study isolates. Rabbits with catheter-induced aortic valve endocarditis were given no treatment, penicillin at 1.2x10(6) IU/8 h intramuscularly, garenoxacin at 20 mg/kg of body weight/12 h intravenously, or levofloxacin at 40 mg/kg/12 h intravenously. For both isolates tested, garenoxacin area under the curve (AUC)/MIC and maximum concentration of drug in serum (Cmax)/MIC ratios were 368 and 91, respectively. Rabbits were sacrificed after 3 days of treatment; cardiac valve vegetations were aseptically removed and quantitatively cultured. For S. mitis group experimental endocarditis, all studied antimicrobial agents were more active than no treatment (P<0.001), whereas for S. sanguinis group endocarditis, no studied antimicrobial agents were more active than no treatment. We conclude that AUC/MIC and Cmax/MIC ratios may not predict activity of some quinolones in experimental viridans group endocarditis and that garenoxacin and levofloxacin may not be ideal choices for serious infections caused by some quinolone-susceptible viridans group streptococci.

Animals↗

Sonication of explanted prosthetic components in bags for diagnosis of prosthetic joint infection is associated with risk of contamination.

Explanted orthopedic implants from 54 patients with aseptic failure and 24 patients with prosthetic knee or hip infection were sonicated in polyethylene bags. The sensitivities of periprosthetic tissue and sonicate fluid cultures for the diagnosis of prosthetic joint infection were 54% and 75%, whereas the specificities were 98% and 87%, respectively. Sonication in bags improved bacterial recovery from the surface of orthopedic implants; however, it lacked specificity, due to bag leakage.

Adult↗

Daptomycin treatment of Staphylococcus aureus experimental chronic osteomyelitis.

BACKGROUND: Infection due to methicillin-resistant Staphylococcus aureus (MRSA) is increasingly common in nosocomial and community settings. Daptomycin is a cyclic lipopeptide anti-infective with activity against MRSA, approved for treatment of complicated skin and skin structure infections. Daptomycin may be useful in systemic or local treatment of chronic osteomyelitis. METHODS: We measured mechanical strength of daptomycin- and vancomycin-loaded polymethylmethacrylate (PMMA), assayed in vivo release of daptomycin and vancomycin from daptomycin- and vancomycin-loaded PMMA, respectively, and compared the efficacy of two systemic doses of daptomycin with that of vancomycin, each with or without the respective anti-infective loaded into PMMA, using a rat model of MRSA chronic osteomyelitis. RESULTS: Neither tensile nor compressive strength of PMMA was impacted by impregnation with these antimicrobials at a concentration of 7.5% by weight. The peak concentrations of daptomycin and vancomycin in rat tibial bone surrounding a 7.5% daptomycin- and vancomycin-loaded 3 mm PMMA bead were 178 and 49 mg/L, respectively. In the treatment of experimental osteomyelitis, rats assigned to no treatment, daptomycin 50 mg/kg subcutaneously twice daily, daptomycin 60 mg/kg subcutaneously twice daily, and vancomycin 50 mg/kg intraperitoneally twice daily had 6.4, 4.1, 4.0 and 4.5 median log10 cfu/g of bone at the end of 21 days of therapy. All systemic anti-infectives studied were more active than was no treatment. Daptomycin- or vancomycin-loaded PMMA did not, however, exhibit microbiological efficacy alone or adjunctively, as assessed 21 days after implantation. CONCLUSIONS: Daptomycin is released from PMMA in vivo at a rate similar to that of vancomycin. Systemic daptomycin is as active as vancomycin in a rat model of chronic MRSA experimental osteomyelitis.

Animals↗

Outcome of prosthetic joint infection in patients with rheumatoid arthritis: the impact of medical and surgical therapy in 200 episodes.

BACKGROUND: Prosthetic joint infection in patients with rheumatoid arthritis is a serious complication of total joint arthroplasty. Little information is available on the outcome of medical and surgical treatments of prosthetic joint infection in patients with rheumatoid arthritis. METHODS: We conducted a retrospective analysis of all patients with rheumatoid arthritis and a total hip or total knee arthroplasty infection evaluated at Mayo Clinic (Rochester, MN) between 1 January 1969 and 31 December 1995. RESULTS: A total of 200 first episodes of prosthetic joint infection in 160 patients with rheumatoid arthritis were diagnosed during the study period. Thirty-seven percent of prosthetic joint infection episodes were due to Staphylococcus aureus. Of these episodes, 23% and 19% were treated with debridement and retention of components and 2-stage exchange, respectively. The type of surgical procedure was the only analyzed clinical variable that was associated with treatment failure (P < .001). Rates of 5-year survival free of treatment failure for patients with prosthetic joint infection episodes treated with debridement and retention of components, 2-stage exchange, and resection arthroplasty were 32% (95% confidence interval [CI], 21%-49%), 79% (95% CI, 66%-93%), and 61% (95% CI, 49%-74%), respectively. CONCLUSIONS: S. aureus is the most common pathogen among patients with rheumatoid arthritis with prosthetic joint infection. Two-stage exchange was used in only 19% of the prosthetic joint infection episodes among patients with rheumatoid arthritis during the study period, but it was associated with the best outcome. The variable most strongly associated with the outcome was the type of surgical procedure.

Adult↗

Prosthetic vascular graft infection: a risk factor analysis using a case-control study.

OBJECTIVES: Several factors have been anecdotally reported to increase the risk of prosthetic vascular graft infection (PVGI), a serious complication with high mortality and limb amputation rates. The goal of this study is to confirm purported risk factors using a well-designed statistical model. METHODS: Patients undergoing vascular graft placement at Mayo Clinic Rochester between January 1, 1982 and December 31, 2002 were retrospectively evaluated, excluding redo cases. PVGI cases had to meet one of the following criteria: perigraft air or fluid >8 weeks postoperatively, positive Gram stain or cultures of graft or perigraft material, intraoperative gross purulence, failure of graft incorporation, or exposed graft. Each case had two controls matched for age, gender and date of surgery. Duration of follow-up for a given control had to be at least equal to the time to infection of the corresponding case. Demographic and other clinical data were collected for each patient. RESULTS: Fifty-one cases and 102 controls met the inclusion criteria. Median age was 68 years. Staphylococcal species were identified in 45% of the total number of cases, and 60% of cases with a recovered organism. Univariate analysis identified groin incision, wound complication and wound infection as significant risk factors for PVGI (p<0.005 for all three factors). After adjusting for age and surgery date, multivariate analysis confirmed the statistical significance of groin incision and wound infection as risk factors for PVGI. CONCLUSIONS: This is the first published risk factor analysis that includes statistical evaluation in a case-control study of PVGI. Groin incision, wound complication, and wound infection are significantly associated with developing PVGI. These findings will assist in identifying patients at increased risk of developing subsequent infection. SUMMARY: In order to confirm purported risk factors of prosthetic vascular graft infections (PVGI), a well designed case-control study was conducted at Mayo Clinic, Rochester, MN. Univariate and multivariate analyses of 51 cases and 102 controls identified three statistically significant risk factors for the development of PVGI: groin incision, wound complication, and wound infection.

Adult↗

Temporal trends in infective endocarditis: a population-based study in Olmsted County, Minnesota.

CONTEXT: Limited data exist regarding population-based epidemiologic changes in incidence of infective endocarditis (IE). OBJECTIVE: To evaluate temporal trends in the incidence and clinical characteristics of IE. DESIGN, SETTING, AND PATIENTS: Population-based survey using the resources of the Rochester Epidemiology Project of Olmsted County, Minnesota. One hundred seven IE episodes occurred in 102 Olmsted County residents between 1970 and 2000. The modified Duke criteria were used to validate the diagnosis of definite or possible IE. MAIN OUTCOME MEASURES: Incidence of IE, proportion of patients with underlying heart disease, and causative microorganisms and clinical characteristics. RESULTS: Age- and sex-adjusted incidence of IE ranged from 5.0 to 7.0 cases per 100,000 person-years during the study period and did not change significantly over time (P = .42 for trend). Infective endocarditis caused by viridans group streptococci was the most common organism-specific subgroup, with an annual adjusted incidence of 1.7 to 3.5 cases per 100,000; in comparison, IE due to Staphylococcus aureus had an annual adjusted incidence of 1.0 to 2.2 cases per 100,000. No time trend was detected for either pathogen group (P = .63 and P = .66, respectively). An increasing temporal trend was observed in the proportions of prosthetic valve IE cases (P = .09). Among people with underlying heart disease, there was an increasing temporal trend in mitral valve prolapse (P = .04) and a decreasing trend in rheumatic heart disease (P = .08). However, the absolute numbers were small. There was no time trend in rates of valve surgery or 6-month mortality during the study period (P = .97 and P = .59, respectively). CONCLUSIONS: In this community-based temporal trend study, we found no substantial change in the incidence of IE over the past 3 decades. Viridans group streptococci continue to outnumber S aureus as the most common causative organisms of IE in this population.

Adult↗

Infective endocarditis: diagnosis, antimicrobial therapy, and management of complications: a statement for healthcare professionals from the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease in the Young, and the Councils on Clinical Cardiology, Stroke, and Cardiovascular Surgery and Anesthesia, American Heart Association: endorsed by the Infectious Diseases Society of America.

BACKGROUND: Despite advances in medical, surgical, and critical care interventions, infective endocarditis remains a disease that is associated with considerable morbidity and mortality. The continuing evolution of antimicrobial resistance among common pathogens that cause infective endocarditis creates additional therapeutic issues for physicians to manage in this potentially life-threatening illness. METHODS AND RESULTS: This work represents the third iteration of an infective endocarditis "treatment" document developed by the American Heart Association under the auspices of the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease of the Young. It updates recommendations for diagnosis, treatment, and management of complications of infective endocarditis. A multidisciplinary committee of experts drafted this document to assist physicians in the evolving care of patients with infective endocarditis in the new millennium. This extensive document is accompanied by an executive summary that covers the key points of the diagnosis, antimicrobial therapy, and management of infective endocarditis. For the first time, an evidence-based scoring system that is used by the American College of Cardiology and the American Heart Association was applied to treatment recommendations. Tables also have been included that provide input on the use of echocardiography during diagnosis and treatment of infective endocarditis, evaluation and treatment of culture-negative endocarditis, and short-term and long-term management of patients during and after completion of antimicrobial treatment. To assist physicians who care for children, pediatric dosing was added to each treatment regimen. CONCLUSIONS: The recommendations outlined in this update should assist physicians in all aspects of patient care in the diagnosis, medical and surgical treatment, and follow-up of infective endocarditis, as well as management of associated complications. Clinical variability and complexity in infective endocarditis, however, dictate that these guidelines be used to support and not supplant physician-directed decisions in individual patient management.

Ambulatory Care↗

In vitro activity of daptomycin against clinical isolates of Gram-positive bacteria.

We determined the activity of daptomycin, a recently FDA-approved antimicrobial agent, against clinical isolates of Gram-positive bacteria, including viridans group streptococci (16 Streptococcus mitis species group, 12 S. mutans species group, 9 S. anginosus species group, 8 S. sanguinis species group, 5 S. salivarius species group) from patients with infective endocarditis, 32 methicillin-resistant Staphylococcus aureus, 32 high-level penicillin-resistant Streptococcus pneumoniae, 38 vancomycin-resistant enterococci (including 1 linezolid-resistant isolate), and the following unusual Gram-positive bacteria: 3 Listeria monocytogenes, 4 Erysipelothrix rhusiopathiae, 9 Corynebacterium species, 10 Abiotrophia/Granulicatella species, 2 Rothia (Stomatococcus) mucilaginosus, and 4 Gemella morbillorum. Daptomycin minimum inhibitory concentration (MIC)(90) values for the viridans group streptococci, methicillin-resistant S. aureus, penicillin-resistant S. pneumoniae, and Enterococcus species were 0.5, 0.5, < or =0.125, and 4 microg/ml, respectively. The daptomycin MIC range for the unusual Gram-positive bacteria was < or =0.125-2 microg/ml. We conclude that daptomycin has in vitro activity against viridans group streptococci associated with endocarditis as well as against several types of unusual Gram-positive bacteria that can cause endocarditis.

Anti-Bacterial Agents↗