rifampin and Enterobacteriaceae-Infections

Topics: Adult; Anti-Bacterial Agents; Cephaloridine; Enterobacteriaceae Infections; Fusidic Acid; Gentamicins; Humans; Infant; Infections; Lincomycin; Nalidixic Acid; Penicillin Resistance; Penicillins; Pseudomonas Infections; Respiratory Tract Infections; Rifampin; Sulfamethoxazole; Tuberculosis; Urinary Tract Infections

Through their action on DNA replication, anticancer chemotherapies could increase the basal mutation rate in bacteria and increase the risk of selecting antibiotic resistant mutants. We investigated the impact of several drugs on a beta-lactamase model using KPC-type carbapenemase-producing Enterobacteriaceae. We studied the impact of anticancer chemotherapies used in pediatric hematologic malignancies on 7 clinical isolates of Enterobacteriaceae producing KPC-type carbapenemases. We compared the mutation rates from cultures with/without chemotherapy on ceftazidime-avibactam, rifampicin and ceftazidime-avibactam combined with meropenem media. Mechanisms of ceftazidime-avibactam resistance were explored on a subset of mutants. After exposure to some cytotoxic molecules, the bacterial mutation rates leading to ceftazidime-avibactam and to rifampicin resistance increased up to 10

Topics: Anti-Bacterial Agents; Antineoplastic Agents; Azabicyclo Compounds; Bacterial Proteins; beta-Lactamases; Carbapenem-Resistant Enterobacteriaceae; Ceftazidime; Drug Combinations; Drug Resistance, Bacterial; Enterobacteriaceae Infections; Genome, Bacterial; Humans; Meropenem; Microbial Sensitivity Tests; Mutation; Rifampin; Whole Genome Sequencing

In bacteria, complex adaptive processes are involved during transition from the planktonic to the biofilm mode of growth, and mutator strains are more prone to producing biofilms. Enterobacteriaceae species were isolated from urinary tract infections (UTIs; 222 strains) and from bloodstream infections (BSIs; 213 strains). Relationship between the hypermutable phenotype and biofilm forming capacity was investigated in these clinical strains. Mutation frequencies were estimated by monitoring the capacity of each strain to generate mutations that conferred rifampicin resistance on supplemented medium. Initiation of biofilm formation was assayed by determining the ability of the cells to adhere to a 96-well polystyrene microtitre plate. UTI Enterobacteriaceae strains showed significantly higher biofilm-forming capacity: 63.1% (54.0% for E. coli strains) vs. 42.3% for BSI strains (47.7% for E. coli). Strains isolated from UTIs did not present higher mutation frequencies than those from BSIs: contrary to what has been widely described for P. aeruginosa strains, isolated from pulmonary samples in patients suffering from cystic fibrosis, no relationship was found between the hypermutator phenotype in Enterobacteriaceae and the ability to initiate a biofilm.

Topics: Biofilms; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Mutation; Rifampin

Limited antimicrobials remain active for treating severe infections due to KPC-producing pathogens, and optimal regimens have not been established. In murine thigh infections caused by nine KPC-producing clinical strains of Enterobacteriaceae (meropenem MICs, 1 to 4 μg/ml), we evaluated the activities of tigecycline, colistin, meropenem, rifampin, and gentamicin in single and combination regimens lasting for 24 h and 48 h. Rifampin, tigecycline, and gentamicin were the most effective monotherapies, reducing significantly the CFU counts yielded from thighs infected by 88.9 to 100%, 77.8 to 88.9%, and 66.7 to 88.9% of strains, respectively; meropenem and colistin alone exhibited considerably lower performance (significant CFU reduction in 33.3% and 22.2 to 33.3% of the strains, respectively). The addition of rifampin or gentamicin to tigecycline produced synergistic effect in most strains, while antagonism was observed in 33.3 to 44.4% of the strains when colistin was added to tigecycline and in 44.4 to 55.5% of the strains for meropenem combination with tigecycline. Tigecycline combinations with gentamicin or with rifampin caused higher CFU reductions than did tigecycline plus colistin or plus meropenem with almost all strains. Furthermore, tigecycline plus gentamicin was significantly more effective than tigecycline plus colistin or tigecycline plus meropenem in 33.3 to 44.4% and 55.5 to 66.7% of the strains, respectively, while tigecycline plus rifampin significantly outperformed tigecycline plus colistin and tigecycline plus meropenem in 33.3% and 66.7 to 77.8% of the strains, respectively. Overall, our in vivo study showed that tigecycline plus rifampin or plus gentamicin is a robust regimen against soft tissue infections caused by KPC-producing strains. The combinations of tigecycline with colistin or meropenem should be considered with caution in clinical practice.

Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Colistin; Colony Count, Microbial; Drug Synergism; Drug Therapy, Combination; Enterobacteriaceae Infections; Escherichia coli; Female; Gentamicins; Klebsiella pneumoniae; Meropenem; Mice; Microbial Sensitivity Tests; Minocycline; Rifampin; Thienamycins; Thigh; Tigecycline

The New Delhi metallo-β-lactamase gene (bla(NDM-1)) has emerged as a worldwide concern among isolates of Enterobacteriaceae. Its epidemiology is been strongly associated with travel and healthcare on the Indian Subcontinent. We report two cases of urinary tract infection with Enterobacteriaceae harboring a bla(NDM-1). Both cases presented as infection in community-dwelling individuals in Australia and were associated with travel to the Indian Subcontinent. One isolate of Escherichia coli harbored the previously undescribed enzyme variant bla(NDM-3), differing from bla(NDM-1) by a single nonsynonymous SNP conferring a putative peptide sequence change at the 95th position (ASP→ASN). The second was an Enterobacter cloacae harboring bla(NDM-1). Further genetic characterization included identification of additional β-lactamase and aminoglycoside resistance genes. Legacy antimicrobials were used for treatment. Oral therapy with nitrofurantoin was successful in one case, while combination of colistin and rifampicin was required in the second patient. Such infection, due to extensively drug-resistant pathogens, poses significant challenges in balancing the efficacy and toxicity of potential antimicrobial therapies.

Topics: Adult; Aged; Anti-Bacterial Agents; beta-Lactamase Inhibitors; beta-Lactamases; Colistin; Drug Resistance, Multiple, Bacterial; Enterobacter cloacae; Enterobacteriaceae Infections; Escherichia coli; Female; Humans; Male; Nitrofurantoin; Polymorphism, Single Nucleotide; Rifampin; Urinary Tract Infections

The objective of this report is to discuss the efficacy of in situ replacement for treating mycotic aneurysm, particularly using rifampicin-bonded grafts and omental pedicle grafts, on the basis of our 7 years of experience.. Between December 2003 and December 2010, we performed surgical treatments in 23 patients (for the thoracic aorta in 6 patients, for the thoracoabdominal aorta in 8 patients, and for the abdominal aorta in 9 patients; 7 emergency, 10 urgent, and 6 elective operations) with mycotic aneurysm by using rifampicin-bonded grafting and omental pedicle grafting.. One patient died in hospital because of local recurrent infection. One patient required an additional operation on another aortic site, and 3 patients had spinal cord injuries (2 transient and 1 permanent). Overall survival at 5 years was 95%, and the rate of freedom from aortic events at 5 years was 86%.. In situ replacement using rifampicin-bonded grafting and omental pedicle grafting is effective for treating mycotic aneurysms of the thoracic and abdominal aorta.

Topics: Aged; Aged, 80 and over; Aneurysm, Infected; Anti-Bacterial Agents; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Bacteremia; Blood Vessel Prosthesis Implantation; Combined Modality Therapy; Elective Surgical Procedures; Enterobacteriaceae Infections; Female; Gram-Positive Bacterial Infections; Humans; Male; Middle Aged; Omentum; Polyethylene Terephthalates; Retrospective Studies; Rifampin; Stents; Surgical Flaps; Treatment Outcome

We determined minimum inhibitory concentrations of rifampicin, nitrofurantoin, amoxicillin-clavulanic acid, and cefdinir, plus a combination of amoxicillin-clavulanic acid and cefdinir by broth microdilution for mainly wound isolates of Escherichia coli and Klebsiella pneumoniae. E. coli and K. pneumoniae susceptibilities increased by combining amoxicillin-clavulanic acid and cefdinir.

Topics: Administration, Oral; Amoxicillin-Potassium Clavulanate Combination; Anti-Bacterial Agents; Cefdinir; Cephalosporins; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae Infections; Escherichia coli; Humans; Klebsiella pneumoniae; Microbial Sensitivity Tests; Nitrofurantoin; Rifampin; Wound Infection

We determined the mutation frequencies of 59 nosocomial isolates of Enterobacter cloacae, and investigated their association with antimicrobial susceptibility, genotype, and history of exposure to antimicrobials. The frequencies of mutations leading to rifampicin resistance ranged from 5.8 × 10(-9) to 8.0 × 10(-6) (median, 5.0 × 10(-8)). Seven of the 59 (12%) isolates were graded as strong mutators exhibiting a more than 50-fold increase in the mutation frequency relative to that of E. cloacae ATCC 13047, and 30 (52%) were graded as weak mutators exhibiting a more than five-fold and not more than 50-fold increase in the mutation frequency. The isolates with higher grade of mutation frequency were resistant to significantly more antimicrobials (medians of two, one and zero agents for strong mutators, weak mutators and non-mutators, respectively; p 0.0078). The 59 isolates were classified into 36 genotypes, and all of the seven strong mutators had distinct genotypes. Mutation frequencies varied more than 10(2)-fold within a clone. In patient-based, univariate analysis, intensive-care unit admission, dense antimicrobial exposure (glycopeptide or multiple classes) and repetitive detection of this species were significantly more common among all of the four patients from whom strong mutators were obtained. Strong mutators are highly prevalent in surgical isolates of E. cloacae. Higher mutation frequency was associated with antimicrobial resistance and repetitive detection, and may contribute to the adaptability of this species.

Topics: Anti-Bacterial Agents; Bacterial Typing Techniques; Cross Infection; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Enterobacter cloacae; Enterobacteriaceae Infections; Genotype; Humans; Molecular Typing; Prevalence; Rifampin

Enterobacter cloacae is an emerging clinical pathogen that may be responsible for nosocomial infections. Management of these infections is often difficult, owing to the high frequency of strains that are resistant to disinfectants and antimicrobial agents in the clinical setting. Multidrug efflux pumps, especially those belonging to the resistance-nodulation-division family, play a major role as a mechanism of antimicrobial resistance in gram-negative pathogens. In the present study, we cloned and sequenced the genes encoding an AcrAcB-TolC-like efflux pump from an E. cloacae clinical isolate (isolate EcDC64) showing a broad antibiotic resistance profile. Sequence analysis showed that the acrR, acrA, acrB, and tolC genes encode proteins that display 79.8%, 84%, 88%, and 82% amino acid identities with the respective homologues of Enterobacter aerogenes and are arranged in a similar pattern. Deletion of the acrA gene to yield an AcrA-deficient EcDC64 mutant (EcDeltaacrA) showed the involvement of AcrAB-TolC in multidrug resistance in E. cloacae. However, experiments with an efflux pump inhibitor suggested that additional efflux systems also play a role in antibiotic resistance. Investigation of several unrelated isolates of E. cloacae by PCR analysis revealed that the AcrAB system is apparently ubiquitous in this species.

Topics: Bacterial Proteins; Base Sequence; beta-Lactamases; Carrier Proteins; Cloning, Molecular; DNA, Bacterial; Drug Resistance, Bacterial; Enterobacter cloacae; Enterobacteriaceae Infections; Genes, MDR; Genetic Vectors; Humans; Microbial Sensitivity Tests; Molecular Sequence Data; Plasmids; Porins

The biological properties of Edwardsiella ictaluri RE-33 rifampicin-mutant and its parent strain EILO were analysed. RE-33 is an avirulent isolate used as a modified live vaccine against enteric septicaemia of catfish. Electrophoretic analysis of lipopolysaccharide (LPS) patterns showed high homology between both isolates. Further characterization of LPS by immunoblotting revealed the main differences in LPS composition. The RE-33 isolate lacks the high molecular weight bands of LPS (HMW-LPS). Outer membrane protein analysis also showed some immunological differences between RE-33 and the EILO parent strain. Only two fingerprinting techniques, fatty acid composition analysis and Biolog phenotypic profiles, were able to discriminate between both isolates.

Topics: Animals; Bacterial Outer Membrane Proteins; Drug Resistance, Bacterial; Edwardsiella ictaluri; Enterobacteriaceae Infections; Fatty Acids; Fish Diseases; Genome, Bacterial; Ictaluridae; Lipopolysaccharides; Mutation; Phenotype; Rifampin

Topics: Drug Resistance, Microbial; Enterobacter; Enterobacteriaceae Infections; Humans; Lactobacillus; Male; Middle Aged; Peritoneal Dialysis, Continuous Ambulatory; Peritonitis; Rifampin; Vancomycin

Thirty-two patients were treated by ofloxacin on bacteriological documented infections. They were Enterobacterias: n = 15 (MIC less than or equal to 0.06 to 0.5 microgram/ml); Pseudomonas aeruginosa and Acinetobacter: n = 1 (MIC 0.5 and 4 micrograms/ml); Staphylococcus: n = 6 (MIC less than or equal to 0.06 to 4 micrograms/ml); Pneumococcus: n = 1; Mycoplasma: n = 1; Chlamydia psittaci: n = 2; Legionella pneumophila: n = 1; Rickettsias: n = 4 (three mediterranean fevers one query fever). Ofloxacin was given orally from 400 to 800 mg per day (5 to 15 mg/kg/day). It was used alone 26 times and on 6 occasions it was associated with rifampin on 6 staphylococcal infections. On 19 cases it was used after failure or intolerance of initial therapy. Thirty times it was the first antibiotic substance used. Results were good mainly: 1) on nine pneumonitis (enterobacterias: 4; Pneumococcus: 1; Mycoplasma: 1; Chlamydia: 2; Legionella: 1) during a mean duration of twenty days; 2) urinary infections (n:7) provoked by E. coli and Enterobacter cloacae (mean duration: 20 days); 3) 4 osteo-articular-infections (mean duration: 77 days); 4) Rickettsial infections (n:4) during a mean duration of 11 days. Results are particularly noteworthy because patients treated had severe infections: 12 bacteremias, 1 endocarditis and 1 purulent meningitis. None severe adverse effect was observed.

Topics: Adolescent; Adult; Aged; Anti-Infective Agents; Drug Therapy, Combination; Enterobacteriaceae Infections; Female; Humans; Male; Middle Aged; Ofloxacin; Oxazines; Respiratory Tract Infections; Rifampin; Staphylococcal Infections; Urinary Tract Infections

A 2-month-old infant with Enterobacter osteomyelitis complicating total parenteral nutrition was successfully treated with rifampicin and chloramphenicol. No untoward side effects attributed to rifampicin has been noted despite prolonged administration of rifampicin.

Topics: Chloramphenicol; Drug Therapy, Combination; Enterobacter; Enterobacteriaceae Infections; Humans; Infant; Male; Osteomyelitis; Parenteral Nutrition; Parenteral Nutrition, Total; Rifampin

Polymyxin B and rifampin were given to 12 patients with multi-drug-resistant nosocomial Serratia marcescens infections. Eight cures were achieved; drug hepatotoxicity occurred once; one fatal suprainfection was encountered; and two patients died during therapy of causes related to severe underlying illnesses. Polymyxin B and rifampin were uniformly synergistic in vitro against the infecting strains and against 40 additional clinical isolates of S. marcescens.

Topics: Adult; Aged; Drug Resistance, Microbial; Enterobacteriaceae Infections; Female; Humans; Male; Middle Aged; Polymyxin B; Polymyxins; Rifampin; Serratia marcescens

Topics: Animals; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Enterobacteriaceae; Enterobacteriaceae Infections; Escherichia coli; Mice; Mutation; Proteus vulgaris; Rifampin; Salmonella typhimurium; Shigella dysenteriae; Trimethoprim

All of 16 infants with neonatal meningitis treated during a 30-month period were found to have accompanying ventriculitis at the time of the initial ventricular puncture. Fifteen of these infants were caused by gramm-negative organisms. All infants received antibiotics systemically and intraventricularly via an implanted ventriculostomy reservoir or by direct ventricular injection. Antibiotic concentrations within the ventricular fluid were monitored during chemotherapy; the complications encountered during treatment are discussed. Fifteen infants survived the infection; of these, seven infants were normal at follow-up examinations. In our experience intraventricular chemotherapy as an adjunct to systemic administration of antibiotics has greatly reduced the mortality rate in neonatal meningitis.

Topics: Ampicillin; Anti-Bacterial Agents; Cerebral Ventricles; Enterobacteriaceae Infections; Female; Flavobacterium; Gentamicins; Humans; Infant, Newborn; Infant, Newborn, Diseases; Injections, Intramuscular; Injections, Intraventricular; Male; Meningitis; Rifampin

Topics: Anti-Bacterial Agents; Bacterial Infections; Carbenicillin; Cephalexin; Cephaloglycin; Cephalosporins; Enterobacteriaceae Infections; Gentamicins; Humans; Pseudomonas Infections; Rifampin; Staphylococcal Infections

Topics: Adult; Aged; Enterobacteriaceae Infections; Female; Humans; Male; Middle Aged; Rifampin; Urinary Tract Infections

Topics: Animals; Dermatomycoses; Drug Resistance, Microbial; Enterobacteriaceae Infections; Guinea Pigs; Humans; Male; Microbial Sensitivity Tests; Prostatitis; Pyoderma; Rabbits; Rats; Rifampin; Skin Diseases, Infectious; Staphylococcal Infections; Streptococcal Infections; Urethritis; Urinary Tract Infections