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Krus D, Kahn F, Nilson B, Sunnerhagen T, Rasmussen M. Blood culture time to positivity in non-β-hemolytic streptococcal bacteremia as a predictor of infective endocarditis-a retrospective cohort study. Eur J Clin Microbiol Infect Dis 2021; 41:325-329. [PMID: 34654986 PMCID: PMC8770443 DOI: 10.1007/s10096-021-04339-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 08/23/2021] [Indexed: 11/24/2022]
Abstract
Non-β-hemolytic streptococci (NBHS) cause infective endocarditis (IE) and a short blood culture time to positivity (TTP) is associated with risk of IE in bacteremia with other pathogens. In this retrospective population-based cohort study, we investigate if TTP is associated to IE or mortality. Of 263 episodes with NBHS bacteremia, 28 represented IE and the median TTP did not differ significantly between episodes with IE (15 h) and non-IE (15 h) (p=0.51). TTP was similar among those who survived and those who died within 30 days. However, TTP significantly differed when comparing the different streptococcal groups (p<0.001).
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Affiliation(s)
- David Krus
- Department for Clinical Sciences Lund, Division of Infection Medicine, Medical Faculty, Lund University, BMC B14, Tornavägen 10, 221 84, Lund, Sweden
| | - Fredrik Kahn
- Department for Clinical Sciences Lund, Division of Infection Medicine, Medical Faculty, Lund University, BMC B14, Tornavägen 10, 221 84, Lund, Sweden.,Division for Infectious Diseases, Skåne University Hospital, Lund, Sweden
| | - Bo Nilson
- Department of Laboratory Medicine Lund, Division of Medical Microbiology, Medical Faculty, Lund University, Lund, Sweden.,Department of Clinical Microbiology, Office for Medical Services, Region Skåne, Lund, Sweden
| | - Torgny Sunnerhagen
- Department for Clinical Sciences Lund, Division of Infection Medicine, Medical Faculty, Lund University, BMC B14, Tornavägen 10, 221 84, Lund, Sweden.,Department of Clinical Microbiology, Office for Medical Services, Region Skåne, Lund, Sweden
| | - Magnus Rasmussen
- Department for Clinical Sciences Lund, Division of Infection Medicine, Medical Faculty, Lund University, BMC B14, Tornavägen 10, 221 84, Lund, Sweden. .,Division for Infectious Diseases, Skåne University Hospital, Lund, Sweden.
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Patil SM, Arora N, Nilsson P, Yasar SJ, Dandachi D, Salzer WL. Native Valve Infective Endocarditis with Osteomyelitis and Brain Abscess Caused by Granulicatella adiacens with Literature Review. Case Rep Infect Dis 2019; 2019:4962392. [PMID: 31467742 PMCID: PMC6701334 DOI: 10.1155/2019/4962392] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 06/22/2019] [Accepted: 07/07/2019] [Indexed: 12/11/2022] Open
Abstract
Granulicatella adiacens is a type of NVS (nutritionally variant streptococci) rarely causing infective endocarditis (IE). NVS are fastidious and unable to sustain growth on routine culture media due to lack of specific nutrients. Endocarditis caused by NVS due to their virulence is associated with higher treatment failures and mortality rates. New antimicrobial susceptibility patterns are indicative of a significant rise in penicillin resistance and susceptibility differences between NVS subspecies. Initial empirical therapy is essential as a delay in using the appropriate agent leads to poor results. We present a case of an immunocompetent young female with recent intravenous drug abuse resulting in native mitral valve endocarditis with ruptured chordae tendineae and septic embolization, causing brain abscess and lumbar spine osteomyelitis. She was transferred to a tertiary center where she underwent mitral valve replacement successfully and treated with six weeks of intravenous vancomycin and ertapenem. To our knowledge, ours is the first case report of G. adiacens endocarditis in an adult with brain abscess and osteomyelitis with an excellent response to antibiotic therapy. Based on our case report, literature review, and new antimicrobial susceptibility patterns, updates to treatment guidelines are suggested to improve the therapeutic outcomes.
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Affiliation(s)
- Sachin M. Patil
- Infectious Disease Department, University of Missouri Hospital and Clinic, 1 Hospital Dr, Columbia, MO 65212, USA
| | - Niraj Arora
- Neurology Department, University of Missouri Hospital and Clinic, 1 Hospital Dr, Columbia, MO 65212, USA
| | - Peter Nilsson
- Internal Medicine Department, University of Missouri Hospital and Clinic, 1 Hospital Dr, Columbia, MO 65212, USA
| | - S. J. Yasar
- Cardiology Department, University of Missouri Hospital and Clinic, 1 Hospital Dr, Columbia, MO 65212, USA
| | - Dima Dandachi
- Infectious Disease Department, University of Missouri Hospital and Clinic, 1 Hospital Dr, Columbia, MO 65212, USA
| | - W. L. Salzer
- Infectious Disease Department, University of Missouri Hospital and Clinic, 1 Hospital Dr, Columbia, MO 65212, USA
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Siméon S, Le Moing V, Tubiana S, Duval X, Fournier D, Lavigne JP, Erpelding ML, Gustave CA, Desage S, Chirouze C, Vandenesch F, Tattevin P, Chirouze C, Curlier E, Descottes-Genon C, Hoen B, Patry I, Vettoretti L, Chavanet P, Eicher JC, Gohier-Treuvelot S, Greusard MC, Neuwirth C, Péchinot A, Piroth L, Célard M, Cornu C, Delahaye F, Hadid M, Rausch P, Coma A, Galtier F, Géraud P, Jean-Pierre H, Le Moing V, Sportouch C, Reynes J, Aissa N, Doco-Lecompte T, Goehringer F, Keil N, Letranchant L, Malela H, May T, Selton-Suty C, Bedos N, Lavigne JP, Lechiche C, Sotto A, Duval X, Habensus EI, Iung B, Leport C, Longuet P, Ruimy R, Bellissant E, Donnio PY, Le Gac F, Michelet C, Revest M, Tattevin P, Thebault E, Alla F, Braquet P, Erpelding ML, Minary L, Tubiana S, Bès M, Etienne J, Lelekov-Boissard T, Tristan A, Vandenesch F, Van Belkum A, Rivadeneira F, Vanwamel W, Barbas S, Delonca C, Sussmuth V, Verchère A. Time to blood culture positivity: An independent predictor of infective endocarditis and mortality in patients with Staphylococcus aureus bacteraemia. Clin Microbiol Infect 2019; 25:481-488. [DOI: 10.1016/j.cmi.2018.07.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 07/07/2018] [Accepted: 07/11/2018] [Indexed: 02/06/2023]
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Lebeaux D, Chauhan A, Rendueles O, Beloin C. From in vitro to in vivo Models of Bacterial Biofilm-Related Infections. Pathogens 2013; 2:288-356. [PMID: 25437038 PMCID: PMC4235718 DOI: 10.3390/pathogens2020288] [Citation(s) in RCA: 296] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 05/01/2013] [Accepted: 05/08/2013] [Indexed: 12/13/2022] Open
Abstract
The influence of microorganisms growing as sessile communities in a large number of human infections has been extensively studied and recognized for 30–40 years, therefore warranting intense scientific and medical research. Nonetheless, mimicking the biofilm-life style of bacteria and biofilm-related infections has been an arduous task. Models used to study biofilms range from simple in vitro to complex in vivo models of tissues or device-related infections. These different models have progressively contributed to the current knowledge of biofilm physiology within the host context. While far from a complete understanding of the multiple elements controlling the dynamic interactions between the host and biofilms, we are nowadays witnessing the emergence of promising preventive or curative strategies to fight biofilm-related infections. This review undertakes a comprehensive analysis of the literature from a historic perspective commenting on the contribution of the different models and discussing future venues and new approaches that can be merged with more traditional techniques in order to model biofilm-infections and efficiently fight them.
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Affiliation(s)
- David Lebeaux
- Institut Pasteur, Unité de Génétique des Biofilms, 25 rue du Dr. Roux, 75724 Paris cedex 15, France.
| | - Ashwini Chauhan
- Institut Pasteur, Unité de Génétique des Biofilms, 25 rue du Dr. Roux, 75724 Paris cedex 15, France.
| | - Olaya Rendueles
- Institut Pasteur, Unité de Génétique des Biofilms, 25 rue du Dr. Roux, 75724 Paris cedex 15, France.
| | - Christophe Beloin
- Institut Pasteur, Unité de Génétique des Biofilms, 25 rue du Dr. Roux, 75724 Paris cedex 15, France.
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E P, B D, C F, O D, T V, Am DG. The Inactivation of a New Peptidoglycan Hydrolase Pmp23 Leads to Abnormal Septum Formation in Streptococcus pneumoniae. Open Microbiol J 2008; 2:107-14. [PMID: 19088920 PMCID: PMC2593039 DOI: 10.2174/1874285800802010107] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 07/29/2008] [Accepted: 07/30/2008] [Indexed: 11/22/2022] Open
Abstract
The bacterial peptidoglycan is the major component of the cell wall which integrity is essential to cell survival. In a previous work, we identified, in the positive-Gram pathogen Streptococcus pneumoniae , a unique protein containing a new putative peptidoglycan hydrolytic domain named PECACE (PEptidoglycan CArbohydrate Cleavage Enzyme). In this study, we characterise the physiological function of this protein called Pmp23 (Pneumococcal Membrane Protein of 23 kDa). A cell wall hydrolytic activity is observed with the recombinant protein. Inactivation of the pmp23 gene in the pneumococcus led to a decreased flocculation, an increased sensitivity to β-lactam antibiotics and morphological alterations affecting the formation and localisation of the division septa. Taken together these observations indicate that Pmp23 is a hydrolase whose function is linked to peptidoglycan metabolism at the septum site.
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Affiliation(s)
- Pagliero E
- Laboratoire d'Ingénierie des Macromolécules
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Abstract
Abiotrophia defectiva, one of several nutritionally variant Streptococcus species, is an uncommon but important cause of endocarditis in children. We describe an unusual case complicated by extensive aortitis with pits in the ascending aorta and the proximal aortic arch.
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Affiliation(s)
- Gary W Raff
- Division of Pediatric Cardiac Surgery, University of California San Francisco, San Francisco, CA, USA
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Woo PCY, Fung AMY, Lau SKP, Chan BYL, Chiu SK, Teng JLL, Que TL, Yung RWH, Yuen KY. Granulicatella adiacens and Abiotrophia defectiva bacteraemia characterized by 16S rRNA gene sequencing. J Med Microbiol 2003; 52:137-140. [PMID: 12543919 DOI: 10.1099/jmm.0.04950-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Traditionally, the identification, epidemiology and spectrum of clinical diseases caused by Granulicatella adiacens and Abiotrophia defectiva are dependent upon their phenotypic characterization. During a 6-year period (July 1995-June 2001), seven and two alpha-haemolytic streptococci were identified as G. adiacens and A. defectiva, respectively, by 16S rRNA gene sequencing. Three patients with haematological malignancies and neutropenic fever had primary bacteraemia. Three patients with valvular problems or congenital heart disease had infective endocarditis. A patient with ischemic heart disease and cerebrovascular accident had infected aortic atheroma with dissection. A patient with recurrent pyogenic cholangitis had acute cholangitis and a patient with polypoid cystitis and benign prostatic hypertrophy had acute prostatitis. Four of the nine patients died, including all three with G. adiacens infective endocarditis or infected atheroma. For the seven G. adiacens isolates, the API 20 STREP system successfully identified one and five isolates as G. adiacens with >95 % and 80-90 % confidence, respectively, whereas the Vitek System (GPI) and ATB Expression system (ID32 STREP) successfully identified none and one isolate as G. adiacens. Of the two A. defectiva isolates, none of the three systems successfully identified either of them as A. defectiva. 16S rRNA gene sequencing is the technique of choice for identifying G. adiacens and A. defectiva, and early surgical intervention should be considered when G. adiacens endocarditis is diagnosed.
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Affiliation(s)
- Patrick Chiu-Yat Woo
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Ami Mei-Yuk Fung
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Susanna Kar-Pui Lau
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Benedict Yin-Leung Chan
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Siu-Kau Chiu
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Jade Lee-Lee Teng
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Tak-Lun Que
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Raymond Wai-Hung Yung
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
| | - Kwok-Yung Yuen
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong 2Department of Microbiology, Tuen Mun Hospital, Hong Kong 3Department of Microbiology, Pamela Youde Nethersole Eastern Hospital, Hong Kong 4HKU-Pasteur Research Centre, Hong Kong
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8
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O'Donovan L, Brooker JD. Effect of hydrolysable and condensed tannins on growth, morphology and metabolism of Streptococcus gallolyticus (S. caprinus) and Streptococcus bovis. MICROBIOLOGY (READING, ENGLAND) 2001; 147:1025-1033. [PMID: 11283298 DOI: 10.1099/00221287-147-4-1025] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Streptococcus gallolyticus (S. caprinus) was resistant in vitro to at least 7% (w/v) tannic acid and 4% (w/v) acacia condensed tannin, levels 10-fold greater than those tolerated by S. bovis. Growth of S. gallolyticus in liquid medium was characterized by a lag period which increased, and a growth rate which decreased, with increasing tannin concentration. S. gallolyticus was also more tolerant to the presence of simple phenolic acid monomers than was S. bovis, but the lag period was still concentration dependent. Gallate decarboxylase activity in S. gallolyticus was elevated in the presence of tannic acid or gallic acid but not with other phenolic acids. Scanning electron microscopic analysis showed that both the size and shape of S. gallolyticus and S. bovis changed in response to tannin but only S. gallolyticus was surrounded by an extracellular polysaccharide matrix which accumulated in a tannin-concentration-dependent fashion. Washing of the cells to remove extracellular polysaccharide increased the lag period of S. gallolyticus in the presence of 1% (w/v) tannic acid from 4 h to 6 h. In contrast, increasing extracellular polysaccharide synthesis in S. bovis did not increase its tolerance to tannic acid. These data demonstrate that S. gallolyticus has developed a number of mechanisms to reduce the potential effect of tannins on cell growth, and that these mechanisms provide the organism with a selective advantage over S. bovis when grown in the presence of tannins.
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Affiliation(s)
- L O'Donovan
- Animal Science Department, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia1
| | - J D Brooker
- Animal Science Department, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia1
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Roskell DE, Bowler IC, Barnes P. Treated bacterial endocarditis as a histological mimic of fungal infection. J Clin Pathol 1998; 51:539-40. [PMID: 9797734 PMCID: PMC500810 DOI: 10.1136/jcp.51.7.539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Histological assessment of cardiac valve tissue contributes to the diagnosis of infective endocarditis and is of particular importance in cases in which no organism is cultured. Antibiotic treatment of bacterial endocarditis may lead to abnormal bacterial morphology and staining characteristics. Although in many cases the presence of some residual bacteria of normal appearance makes the diagnosis straightforward, in some only abnormal bacteria may be seen. Unless the appearances of these are interpreted with caution, the presence of larger spherical organisms with the staining properties of a yeast may lead to an erroneous diagnosis of fungal infection.
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Affiliation(s)
- D E Roskell
- Oxford University, Nuffield Department of Pathology and Bacteriology, John Radcliffe Hospital, UK
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10
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Contribution of animal models of infection for the evaluation of the activity of antimicrobial agents. Int J Antimicrob Agents 1997; 9:73-82. [DOI: 10.1016/s0924-8579(97)00035-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/1997] [Indexed: 11/21/2022]
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Abstract
The mortality of IE remains fairly high despite the aggressive use of intravenous antibiotics. Oral treatment of IE is an intriguing concept with many potential advantages over conventional intravenous therapy. Unfortunately, there are insufficient data to justify predominantly oral regimens for the treatment of IE. Trials have shown that oral therapy may have a role in follow-up to short courses of parenteral antibiotics, but these trials are limited by the small number of patients studied. It is important to note that most data for oral treatment of IE have been obtained from studies in patients with histories of IVDA and right-sided S. aureus endocarditis. As mentioned previously, the course of IE in this patient population tends to be less severe, which makes extrapolation of these data to the general population difficult. A need exist for the development of oral antimicrobials with the properties previously mentioned, making them appropriate for use in IE. Currently available oral agents require further study before general recommendations regarding their use in patients with IE can be made. Although successful oral treatment of prosthetic valve endocarditis has been reported, such patients in general should not be considered as appropriate candidates for oral therapy. For now, oral antimicrobial therapy may be appropriate only as follow-up to short-course intravenous therapy, or use in combination with intravenous therapy for IE in select populations whose disease course is less severe or in whom prolonged intravenous therapy is impractical (i.e., intravenous drug users).
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Affiliation(s)
- R E Fuller
- School of Pharmacy, Campbell University, Buies Creek, NC, USA
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12
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Abstract
Bacterial endocarditis is a difficult infection to cure, due to poor penetration of antibiotics into infected vegetations, altered metabolic state of bacteria within the lesion, and absence of adequate host-defense cellular response which could cooperate with antibiotic action. The contribution of animal models to a better understanding of the pathophysiology of the infection and to definition and improvement of therapeutic regimens of endocarditis in humans remains of great importance due to the difficulties encountered in clinical trials. The advantage of the experimental model is that besides the fact that it closely simulates the characteristics of the infection in humans, it provides clear endpoints which allow statistical comparisons among different therapeutic regimens: number of bacteria per gram of tissue, frequency of emergence of resistance, positivity of blood cultures, death vs. survival rates, and percentage of relapses after treatment has been stopped. All these parameters are more sensitive and more easy to study than in humans. The animal model has definitively established that bactericidal therapy is warranted and that in vitro susceptibility tests, especially those evaluating the killing rate, have a good predictive value on the therapeutic outcome. Two main aspects are discussed for their relevance to human therapy: (i) the kinetics of antibiotic diffusion into vegetations, with special reference to data obtained with autoradiography; and (ii) the specificity of some pharmacodynamic aspects of antibiotics in endocarditis, including the clinical consequences of these two parameters with respect to antibiotic dosing regimens and length of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- C Carbon
- Service de Médecine Interne, INSERM U13, Hopital Bichat-Claude Bernard, Paris, France
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Mghir AS, Cremieux AC, Jambou R, Muffat-Joly M, Pocidalo JJ, Carbon C. Dextranase enhances antibiotic efficacy in experimental viridans streptococcal endocarditis. Antimicrob Agents Chemother 1994; 38:953-8. [PMID: 8067775 PMCID: PMC188132 DOI: 10.1128/aac.38.5.953] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In endocarditis, exopolysaccharide production by viridans streptococci has been associated with delayed antimicrobial efficacy in cardiac vegetations. We compared the efficacies of temafloxacin alone and in combination with dextranase, an enzyme capable of hydrolyzing 20 to 90% of the bacterial glycocalyx, in a rabbit model of endocarditis. In in vivo experiments, rabbits were infected intravenously with 10(8) Streptococcus sanguis organisms and were treated 6 days later with temafloxacin (50 mg/kg of body weight intramuscularly twice a day) alone or combined with dextranase (1,000 U per rabbit per day intravenously). After 4 days of treatment (day 11), the animals were sacrificed and vegetations were quantitatively cultured. For ex vivo experiments, rabbits were infected as stated above and, on day 11, vegetations were excised aseptically and incubated in vitro in rabbit serum alone (control) or with temafloxacin or temafloxacin plus dextranase at concentrations similar to peak levels in plasma. In vitro, dextranase alone had no antimicrobial effect. In vivo and ex vivo, temafloxacin combined with dextranase was more effective than temafloxacin alone (P < 0.05). Our results suggest that dextranase is able to increase the effects of temafloxacin by reducing the amount of bacterial glycocalyx in infected vegetations, as confirmed in vitro by electron microscopy showing a markedly reduced amount of glycocalyx and a more clearly visible fibrin matrix.
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Affiliation(s)
- A S Mghir
- Institut National de la Santé et de la Recherche Médicale Unité 13, Hôpital Claude-Bernard Bichat, Paris, France
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PHARMACOKINETIC AND PHARMACODYNAMIC ASPECTS OF THERAPY OF EXPERIMENTAL ENDOCARDITIS. Infect Dis Clin North Am 1993. [DOI: 10.1016/s0891-5520(20)30504-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Cremieux AC, Carbon C. Pharmacokinetic and pharmacodynamic requirements for antibiotic therapy of experimental endocarditis. Antimicrob Agents Chemother 1992; 36:2069-74. [PMID: 1444286 PMCID: PMC245457 DOI: 10.1128/aac.36.10.2069] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- A C Cremieux
- Service de Médecine Interne, Institut National de la Santé et de la Recherche Médicale U13, Hopital Bichat-Claude Bernard, Paris, France
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16
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Cremieux AC, Saleh-Mghir A, Vallois JM, Maziere B, Muffat-Joly M, Devine C, Bouvet A, Pocidalo JJ, Carbon C. Efficacy of temafloxacin in experimental Streptococcus adjacens endocarditis and autoradiographic diffusion pattern of [14C]temafloxacin in cardiac vegetations. Antimicrob Agents Chemother 1992; 36:2216-21. [PMID: 1332590 PMCID: PMC245479 DOI: 10.1128/aac.36.10.2216] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Temafloxacin, a new fluoroquinolone, alone or in combination with tobramycin, was compared with penicillin, tobramycin, and their combination in the therapy of rabbits with endocarditis caused by Streptococcus adjacens GaDT, a new species of nutritionally variant streptococci. Animals were injected intramuscularly for 4 days with temafloxacin (50 mg/kg of body weight twice daily [b.i.d.]) alone or combined with tobramycin (12 mg/kg once daily), with procaine penicillin (150,000 U/kg b.i.d.) alone or combined with tobramycin (12 mg/kg once daily), or with tobramycin (12 mg/kg once daily) alone. Another group of animals was treated with a higher dose of temafloxacin (100 mg/kg b.i.d.). Temafloxacin, penicillin, and tobramycin MICs and MBCs were 1 and 2, 0.015 and 1, and 8 and 16 micrograms/ml, respectively. Time-kill curves showed that the addition of tobramycin to penicillin or temafloxacin increased the killing rate. In vivo, treatment with temafloxacin (50 and 100 mg/kg b.i.d.) alone reduced the bacterial counts in vegetations (3.9 +/- 0.9 and 3.1 +/- 0.8 log10 CFU/g of vegetation) compared with those in the vegetations of control animals (7.5 +/- 0.9 log10 CFU/g of vegetation). This result was similar to that obtained with penicillin alone (4.5 +/- 0.8 log10 CFU/g of vegetation). The combination of temafloxacin (50 mg/kg) and tobramycin was as effective as penicillin plus tobramycin (2.5 +/- 0.3 versus 2.3 +/- 0.4 log10 CFU/g of vegetation, respectively). The autoradiographic pattern of [14C]temafloxacin diffusion into infected cardiac vegetations was studied. Thirty minutes after the end of infusion of 250 microCi of [14C]temafloxacin, the [14C]temafloxacin was homogeneously distributed throughout the vegetations. These data support further evaluation of quinolones in experimental endocarditis.
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Affiliation(s)
- A C Cremieux
- Hôpital Bichat-Claude Bernard, Institut National de la Santé et de la Recherche Médicale, Unité 13, Paris, France
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Abstract
Streptococci requiring either pyridoxal or L-cysteine for growth were first observed 30 years ago as organisms forming satellite colonies adjacent to colonies of "helper" bacteria. Although they were previously considered nutritional mutants of viridans streptococcal species, the nutritionally variant streptococci (NVS) are currently thought to belong to distinct species of the genus Streptococcus. NVS strains may display pleomorphic cellular morphologies, depending on their growth conditions, and are distinguished from most other streptococci by enzymatic and serological characteristics and the presence of a cell wall chromophore. NVS are found as normal inhabitants of the oral cavity, and in addition to their participation in endocarditis, they have been isolated from a wide range of clinical specimens. Endocarditis caused by NVS is often difficult to eradicate; combinations of penicillin and an aminoglycoside are recommended for treatment. The unique physiological features of the NVS contribute to the difficulties encountered in their recovery from clinical specimens and may play a role in the problems associated with successful treatment of NVS endocarditis.
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Affiliation(s)
- K L Ruoff
- Francis Blake Bacteriology Laboratories, Massachusetts General Hospital, Boston 02114
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18
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