Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0014118 (endocarditis)
 15,629 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Earlier studies suggest that ampicillin and amoxicillin are more effective than other beta-lactam agents in killing enterococci, although beta-lactam agents are slowly and incompletely bactericidal against most strains of Enterococcus faecalis. We previously showed that continuous infusion of ampicillin is more effective than intermittent administration in decreasing the number of enterococci in valvular vegetations of rats with catheter-induced endocarditis that are treated for 5 days. In this model, we found ampicillin plus sulbactam more effective than ampicillin alone against a beta-lactamase-producing enterococcal strain with high-level resistance to gentamicin. Daptomycin therapy produced results approximately equal to those of ampicillin plus sulbactam. Vancomycin and teicoplanin given for 5 days at doses producing equivalent serum levels had approximately equal efficacy. However, 10-day therapy with low-dose teicoplanin was considerably more effective than similar treatment with vancomycin. High-dose teicoplanin for 5 days produced sterile valves in 82% of the animals studied.
 ...
PMID:Contribution of animal models in the search for effective therapy for endocarditis due to enterococci with high-level resistance to gentamicin. 131 57

The efficacy of tazobactam, a beta-lactamase inhibitor, in combination with piperacillin, was studied in vitro and in rabbit experimental endocarditis due to a Klebsiella pneumoniae strain (KpR) producing an extended-spectrum beta-lactamase, TEM-3, or its nonproducing variant (KpS). In vitro, piperacillin was active against KpS (MIC = 4 micrograms/ml, MBC = 8 micrograms/ml with 10(7)-CFU/ml inoculum) but not against KpR (MIC = MBC = 256 micrograms/ml). Tazobactam (1 microgram/ml) restored the activity of piperacillin against KpR (MIC = 2 micrograms/ml, MBC = 4 micrograms/ml). Gentamicin was active against both strains (MIC = 0.25 and 0.5 micrograms/ml for KpS and KpR, respectively). The piperacillin-tazobactam-gentamicin combination was synergistic in vitro. The piperacillin/tazobactam ratio in plasma and in vegetations was always lower than the 4/1 injected dose ratio. In vivo, piperacillin (300 mg/kg of body weight four times a day [QID]) was active against KpS but not against KpR. Tazobactam (75 mg/kg QID) was able to restore the in vivo effect of piperacillin (300 mg/kg QID) against KpR (-3.0 log10 CFU/g of vegetation versus that of controls). Gentamicin (4 mg/kg twice a day [BID]) was active against both strains. Compared with controls, the combination of gentamicin plus piperacillin against KpS (-5.6 log10 CFU/g of vegetation), and the gentamicin-piperacillin-tazobactam combination against KpR (-4.4 log10 CFU/g of vegetation) achieved the greatest decrease in bacterial counts in vegetations and were the only regimens that significantly increased the proportion of sterile vegetations. It is concluded that (i) tazobactam was able to restore the effect of piperacillin against a TEM-3 extended-spectrum Beta-lactamase-producing strain of K. pneumoniae, both in vitro and in a severe experimental infection with high inoculum, when used in a 4/1 piperacillin/tazobactam dose ratio; (ii) gentamicin alone was effective because of the high peak/MBC ratio in plasma; (iii) piperacillin-tazobactam-gentamicin, probably because of the effect of gentamicin in reducing bacterial inoculum in vivo, as stressed by the results obtained by piperacillin-gentamicin against KpS, may be the most effective regimen against KpR.
 ...
PMID:Piperacillin, tazobactam, and gentamicin alone or combined in an endocarditis model of infection by a TEM-3-producing strain of Klebsiella pneumoniae or its susceptible variant. 132 34

Nine Haemophilus species strains, all beta-lactamase negative, isolated from patients with endocarditis were tested in killing curve experiments. Antibiotics used were penicillin, amoxicillin, aztreonam alone and in combination with tobramycin, as well as ciprofloxacin alone. Synergism between beta-lactams and tobramycin with reduction of colony counts to zero was seen after 24 h for H. influenzae, H. parainfluenzae and H. segnis strains. Ciprofloxacin was as effective as beta-lactam-tobramycin combinations. The H. aphrophilus strain was not killed as effectively as other strains by any of the antibiotics.
 ...
PMID:Killing curve activity of ciprofloxacin is comparable to synergistic effect of beta-lactam-tobramycin combinations against Haemophilus species endocarditis strains. 138 4

Endocarditis is a rare but potentially lethal manifestation of gonococcal infection. We report the case of a patient with fulminant endocarditis secondary to infection with penicillinase-producing Neisseria gonorrhoeae (PPNG). The patient had rapid deterioration from extensive destruction of the aortic valve with abscess and fistula formation. Lifesaving emergency surgery was performed. To our knowledge this is the first reported case of gonococcal endocarditis secondary to infection with a penicillinase-producing organism.
 ...
PMID:Fulminant endocarditis due to infection with penicillinase-producing Neisseria gonorrhoeae. 141 46

Post-tonsillectomy bacteraemia is a well recognized aetiological factor in streptococcal endocarditis. Prophylactic penicillin has been recommended to reduce its incidence in susceptible patients undergoing tonsillectomy. Recent studies have shown a change in the microflora and an increase in the number of penicillin resistant organisms in the tonsils of patients undergoing tonsillectomy. The aim of this study has been to assess the incidence of post-tonsillectomy bacteraemia, identify the organisms associated with it and review the suitability of penicillin in prophylactic regimens. Of the 32 patients included in the study, 11 (34.4%) had positive post-tonsillectomy blood cultures. We were surprised at this low incidence of bacteraemia and have postulated a possible reason. Haemophilus influenzae was isolated from 4 (36.4%) of the positive cultures and Streptococcus viridans in only 1 (9%). Rather than using penicillin for prophylaxis a beta-lactamase stable antibiotic would be more appropriate.
 ...
PMID:Post-tonsillectomy bacteraemia. 150 85

The efficacy of ticarcillin-clavulanic acid was compared with the efficacies of standard antistaphylococcal agents (flucloxacillin, oxacillin, nafcillin, and vancomycin) and ticarcillin in an experimental model of Staphylococcus aureus endocarditis. Therapy was either initiated soon (8 h) after infection, when numbers of bacteria in aortic valve vegetations were relatively low (approximately 6 to 8 log10 CFU/g), or delayed until 24 h after infection, when the vegetations usually contained greater than 9 log10 CFU/g. Doses of the antibiotic were selected to produce peak concentrations in rat serum similar to those achievable in humans after administration of parenteral therapeutic doses. Ticarcillin-clavulanic acid was more effective overall than ticarcillin alone against endocarditis caused by beta-lactamase-producing strains of S. aureus, illustrating the beta-lactamase-inhibitory activity of clavulanic acid in vivo. Ticarcillin-clavulanic acid was as effective as the standard antistaphylococcal beta-lactam agents flucloxacillin, oxacillin, and nafcillin in these infections, whereas vancomycin was generally less active. These results illustrate the clinical potential of ticarcillin-clavulanic acid in the prophylaxis or therapy of severe staphylococcal infections.
 ...
PMID:Efficacy of ticarcillin-clavulanic acid for treatment of experimental Staphylococcus aureus endocarditis in rats. 151 Apr 59

Endocarditis due to Enterobacter species is very rare. We recently cared for a patient who developed E. cloacae endocarditis following mitral valve replacement with a porcine heterograft, and was successfully treated with antibiotic therapy alone. A review of the literature disclosed an additional 17 well-described cases of enterobacter endocarditis. Two-thirds of the patients had underlying cardiac disease. The mitral valve was most frequently involved (10/16 cases) with 4 of the patients having concomitant aortic valve involvement. The overall mortality rate was 44.4%. Antibiotic therapy of enterobacter endocarditis should consist of the combination of a beta-lactam antibiotic and an aminoglycoside with careful monitoring of blood cultures to assure the adequacy of therapy. Resistance of enterobacter to previously susceptible antibiotics may occur during therapy due to induction of a chromosomally-mediated beta-lactamase, necessitating a change in antimicrobial therapy. Valvular surgery is indicated for patients failing medical management.
 ...
PMID:Enterobacter endocarditis. 164 1

There have been numerous reports on resistance of anaerobic bacteria against antimicrobial agents. Therefore, to assess the situation in Zurich, 187 anaerobic strains of various bacterial genera, isolated from clinical specimens during winter 1990/91, were tested for their susceptibility to antimicrobial agents active against anaerobic bacteria. Besides the Bacteroides fragilis group, which is naturally resistant against penicillin, 30% of isolates of other Bacteroides species were also resistant against penicillin. In general, anaerobes have remained susceptible to cefoxitin, chloramphenicol, clindamycin, imipenem, the 5-nitroimidazoles (metronidazole, ornidazole) as well as combinations of beta-lactam antibiotics with beta-lactamase inhibitors (clavulanic acid, sulbactam and tazobactam). Because rare strains resistant against cefoxitin, clindamycin and beta-lactams plus beta-lactamase inhibitors can be found, at least isolates from specific clinical situations should be tested for antimicrobial susceptibility. These are strains isolated from patients with brain abscess, endocarditis, osteomyelitis, arthritis, infected implants and prosthesis as well as those from persisting or recurrent bacteremia. Because the agar diffusion test yields unreliable results, minimal inhibitory concentration should be determined. Maybe the new 'E test' or the spiral gradient procedure can be used after evaluation.
 ...
PMID:[The sensitivity of anaerobic bacteria to chemotherapeutic agents (Zurich, 1991)]. 181 9

Laboratories that reported isolations of Streptococcus sanguis from blood cultures to the Communicable Disease Surveillance Centre (CDSC) Colindale were requested to submit strains to Bath Public Health Laboratory to allow the prevalence of penicillin tolerance within different biotypes of this species to be studied. One hundred and fifty one Streptococcus spp were received from 78 United Kingdom laboratories in one year. Strains were identified using the API 20 Strep, and minimum inhibitory concentrations (MICs) of penicillin were determined using the spiral gradient plate method. Penicillin tolerance was detected by spraying beta-lactamase over inoculated gradient plates, reincubating for 48 hours and counting the number of surviving organisms represented by colonies. There were 57 different API identification profiles encountered in the survey. Most S sanguis I/1 strains were penicillin tolerant, most S sanguis II strains were non-tolerant. The overall geometric mean MIC of penicillin was considerably lower for S sanguis I/1 than for all other biotypes. The distribution of biotypes and the geometric mean MIC of penicillin for each biotype were not significantly different for infective endocarditis strains than for all strains tested, suggesting little or no association between penicillin tolerance and the seeding of endocardium. When the reactions obtained using API 20 Strep were compared with a recent taxonomic study of viridans streptococci, 22 of 38 S sanguis I/1 strains could be reclassified as S gordonii; all these strains were penicillin tolerant. Such reclassification would allow likely penicillin tolerant strains to be predicted.
 ...
PMID:Incidence of penicillin tolerance among blood culture isolates of Streptococcus sanguis, 1987-88. 186 89

Enterococcal endocarditis is the third most common presentation in native valves, and it is the most refractory. Unique among the streptococci, enterococci are relatively resistant to beta-lactam antibiotics requiring a combination aminoglycoside regimen for cure. Relapse is common even after apparently adequate therapy and may be seen in up to 25% of cases that involve streptomycin-resistant strains. This problem is magnified by the recent appearance of beta-lactamase-producing strains of S. faecalis resistant to both ampicillin and gentamicin. Ciprofloxacin is being investigated with a number of antimicrobials in the attempt to identify superior protocols against troublesome pathogens. However, little published data is available concerning the clinical efficacy of this drug in enterococcal endocarditis. In vitro studies and preliminary trials with animal models have generally been disappointing with broth macrodilution time-kill or agar dilution proving the most reliable in vitro methods for predicting in vivo outcomes. The urgent need to identify new combination drug regimens is underscored not only by the development of new resistance patterns, but by the well-documented toxicities of conventional therapies. The authors present a case of relapsing enterococcal endocarditis caused by a non-beta-lactamase-producing strain of S. faecalis, which demonstrated high-level resistance to streptomycin but not to gentamicin. Relapses occurred despite favorable laboratory data and aggressive beta-lactam-gentamicin therapies. Cure was achieved using oral ciprofloxacin in a combination drug regimen, which is reported here for the first time.
 ...
PMID:Relapsing native-valve enterococcal endocarditis: a unique cure with oral ciprofloxacin combination drug therapy. 190 63


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>