scholarly journals Comparative in vitro Activities of Ceftazidime–Avibactam and Ceftolozane-tazobactam Against Characterized β-Lactamase-producing Pseudomonas aeruginosa

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S367-S367
Author(s):  
Lynn-Yao Lin ◽  
McClain Vail ◽  
Dmitri Debabov ◽  
Ian Critchley

Abstract Background Ceftazidime-avibactam (CAZ-AVI) and ceftolozane-tazobactam (TOL-TAZ) are cephalosporin/β-lactamase inhibitor combinations recently approved for the treatment of complicated intra-abdominal infections (cIAI) and complicated urinary tract infections (cUTI). Both agents are reported to have antibacterial activity against P. aeruginosa including multi-drug-resistant strains, but few studies have directly compared the activities of both agents against the same strains in a single study. This study evaluated the activities of both agents against characterized β-lactamase-producing P. aeruginosa using broth microdilution (BMD) and disk diffusion (DD) methods. Methods A total of 98 clinical isolates of P. aeruginosa, including characterized β-lactamase-producing strains were tested for susceptibility to CAZ-AVI and TOL-TAZ using BMD and DD and results were interpreted using FDA/CLSI breakpoints. The isolates tested included CTX-M (ESBL), AmpC, KPC, OXA and metallo-β-lactamase (MBL) producing organisms. The results from both BMD and DD were analyzed to assess the correlation between the testing methods and ability to differentiate isolates susceptible and resistant to both agents. Results CAZ-AVI and TOL-TAZ exhibited similar MIC values against all isolates with MIC50/90 values of 2 and 16 µg/mL, respectively. When results were interpreted using FDA/CLSI breakpoints, the susceptibility rates for CAZ-AVI and TOL-TAZ were 82.7% and 62.2%, respectively. Isolates resistant to CAZ-AVI were predominantly MBL-producers whereas isolates resistant to TOL-TAZ included both MBL and KPC-producing P. aeruginosa. Both agents were active against AmpC-producing P. aeruginosa and both agents showed good correlation between BMD and DD methods. Conclusion CAZ-AVI and TOL-TAZ were active against β-lactamase-producing subsets of P. aeruginosa isolates in this challenge set. Both AmpC and KPC-producing P. aeruginosa were susceptible to CAZ-AVI whereas TOL-TAZ activity was limited to AmpC-producing organisms. Neither agent was active against MBL-producing organisms. Disclosures L. Y. Lin, Allergan plc: Employee, Salary; M. Vail, Allergan plc: Employee and Intern during study conduct and analysis, Educational support; D. Debabov, Allergan plc: Employee, Salary; I. Critchley, Allergan plc: Employee, Salary

2021 ◽  
Vol 12 (1) ◽  
pp. 16-26
Author(s):  
Kimberly To ◽  
Ruoqiong Cao ◽  
Aram Yegiazaryan ◽  
James Owens ◽  
Kayvan Sasaninia ◽  
...  

Abstract Tuberculosis (TB) caused by Mycobacterium tuberculosis (M. tb) still remains a devastating infectious disease in the world. There has been a daunting increase in the incidence of Type 2 Diabetes Mellitus (T2DM) worldwide. T2DM patients are three times more vulnerable to M. tb infection compared to healthy individuals. TB-T2DM coincidence is a challenge for global health control. Despite some progress in the research, M. tb still has unexplored characteristics in successfully evading host defenses. The lengthy duration of treatment, the emergence of multi-drug-resistant strains and extensive-drug-resistant strains of M. tb have made TB treatment very challenging. Previously, we have tested the antimycobacterial effects of everolimus within in vitro granulomas generated from immune cells derived from peripheral blood of healthy subjects. However, the effectiveness of everolimus treatment against mycobacterial infection in individuals with T2DM is unknown. Furthermore, the effectiveness of the combination of in vivo glutathione (GSH) supplementation in individuals with T2DM along with in vitro treatment of isolated immune cells with everolimus against mycobacterial infection has never been tested. Therefore, we postulated that liposomal glutathione (L-GSH) and everolimus would offer great hope for developing adjunctive therapy for mycobacterial infection. L-GSH or placebo was administered to T2DM individuals orally for three months. Study subjects’ blood was drawn pre- and post-L-GSH/or placebo supplementation, where Peripheral Blood Mononuclear Cells (PBMCs) were isolated from whole blood to conduct in vitro studies with everolimus. We found that in vitro treatment with everolimus, an mTOR (membrane target of rapamycin) inhibitor, significantly reduced intracellular M. bovis BCG infection alone and in conjunction with L-GSH supplementation. Furthermore, we found L-GSH supplementation coupled with in vitro everolimus treatment produced a greater effect in inhibiting the growth of intracellular Mycobacterium bovis BCG, than with the everolimus treatment alone. We also demonstrated the functions of L-GSH along with in vitro everolimus treatment in modulating the levels of cytokines such as IFN-γ, TNF-α, and IL-2 and IL-6, in favor of improving control of the mycobacterial infection. In summary, in vitro everolimus-treatment alone and in combination with oral L-GSH supplementation for three months in individuals with T2DM, was able to increase the levels of T-helper type 1 (Th1) cytokines IFN-γ, TNF-α, and IL-2 as well as enhance the abilities of granulomas from individuals with T2DM to improve control of a mycobacterial infection.


1987 ◽  
Vol 8 (6) ◽  
pp. 241-244 ◽  
Author(s):  
Maury E. Mulligan ◽  
Y.Y. Kwok

AbstractCefixime, a broad-spectrum, orally active cephalosporin, was more active in vitro than ampicillin, cefaclor, cephalothin, and trimethoprim/sulfamethoxazole against 194 nosocomial pathogens of the family Enterobacteriaceae. Activity was especially good against Klebsiella spp, Proteus spp, Serratia spp, and Providencia stuartii. Although gentamicin had equivalent or better activity against Citrobacter spp, Enterobacter spp, Escherichia coli, and Morganella morganii, all 23 of the gentamicin-resistant strains studied were susceptible to Cefixime. Isolates tested were from urinary tract infections, abdominal infections, wounds, vascular infections, and respiratory infections; they were sequentially collected nosocomial pathogens from a single institution. This orally active cephalosporin should be considered for therapy of a variety of nosocomial infections involving gram-negative bacillary pathogens.


2004 ◽  
Vol 57 (6) ◽  
pp. 400-402 ◽  
Author(s):  
KAZUHIKO OTOGURO ◽  
AKI ISHIYAMA ◽  
MIYUKI KOBAYASHI ◽  
HITOMI SEKIGUCHI ◽  
TAKASHI IZUHARA ◽  
...  

2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Manoon Leechawengwongs ◽  
Therdsak Prammananan ◽  
Sarinya Jaitrong ◽  
Pamaree Billamas ◽  
Nampueng Makhao ◽  
...  

ABSTRACT New fluoroquinolones (FQs) have been shown to be more active against drug-resistant Mycobacterium tuberculosis strains than early FQs, such as ofloxacin. Sitafloxacin (STFX) is a new fluoroquinolone with in vitro activity against a broad range of bacteria, including M. tuberculosis. This study aimed to determine the in vitro activity of STFX against all groups of drug-resistant strains, including multidrug-resistant M. tuberculosis (MDR M. tuberculosis), MDR M. tuberculosis with quinolone resistance (pre-XDR), and extensively drug-resistant (XDR) strains. A total of 374 drug-resistant M. tuberculosis strains were tested for drug susceptibility by the conventional proportion method, and 95 strains were randomly submitted for MIC determination using the microplate alamarBlue assay (MABA). The results revealed that all the drug-resistant strains were susceptible to STFX at a critical concentration of 2 μg/ml. Determination of the MIC90s of the strains showed different MIC levels; MDR M. tuberculosis strains had a MIC90 of 0.0625 μg/ml, whereas pre-XDR and XDR M. tuberculosis strains had identical MIC90s of 0.5 μg/ml. Common mutations within the quinolone resistance-determining region (QRDR) of gyrA and/or gyrB did not confer resistance to STFX, except that double mutations of GyrA at Ala90Val and Asp94Ala were found in strains with a MIC of 1.0 μg/ml. The results indicated that STFX had potent in vitro activity against all the groups of drug-resistant M. tuberculosis strains and should be considered a new repurposed drug for treatment of multidrug-resistant and extensively drug-resistant TB.


2010 ◽  
Vol 35 (2) ◽  
pp. 208-209 ◽  
Author(s):  
Yoonkyung Park ◽  
Seong-Cheol Park ◽  
Jin-Young Kim ◽  
Jeong Ok Park ◽  
Chang Ho Seo ◽  
...  

2012 ◽  
Vol 56 (7) ◽  
pp. 3475-3480 ◽  
Author(s):  
Sovitj Pou ◽  
Rolf W. Winter ◽  
Aaron Nilsen ◽  
Jane Xu Kelly ◽  
Yuexin Li ◽  
...  

ABSTRACTSontochin was the original chloroquine replacement drug, arising from research by Hans Andersag 2 years after chloroquine (known as “resochin” at the time) had been shelved due to the mistaken perception that it was too toxic for human use. We were surprised to find that sontochin, i.e., 3-methyl-chloroquine, retains significant activity against chloroquine-resistant strains ofPlasmodium falciparum in vitro. We prepared derivatives of sontochin, “pharmachins,” with alkyl or aryl substituents at the 3 position and with alterations to the 4-position side chain to enhance activity against drug-resistant strains. Modified with an aryl substituent in the 3 position of the 7-chloro-quinoline ring, Pharmachin 203 (PH-203) exhibits low-nanomolar 50% inhibitory concentrations (IC50s) against drug-sensitive and multidrug-resistant strains andin vivoefficacy against patent infections ofPlasmodium yoeliiin mice that is superior to chloroquine. Our findings suggest that novel 3-position aryl pharmachin derivatives have the potential for use in treating drug resistant malaria.


2019 ◽  
Vol 64 (1) ◽  
Author(s):  
Lindsay J. Caverly ◽  
Theodore Spilker ◽  
Linda M. Kalikin ◽  
Terri Stillwell ◽  
Carol Young ◽  
...  

ABSTRACT We tested the in vitro activities of ceftazidime-avibactam, ceftolozane-tazobactam, meropenem-vaborbactam, piperacillin-tazobactam, and 11 other antimicrobial agents against 420 Burkholderia, Achromobacter, Stenotrophomonas, and Pandoraea strains, 89% of which were cultured from respiratory specimens from persons with cystic fibrosis. Among the β-lactam–β-lactamase inhibitor agents, meropenem-vaborbactam had the greatest activity against Burkholderia and Achromobacter, including multidrug-resistant and extensively-drug-resistant strains. None of the newer β-lactam–β-lactamase combination drugs showed increased activity compared to that of the older agents against Stenotrophomonas maltophilia or Pandoraea spp.


2017 ◽  
Vol 61 (12) ◽  
Author(s):  
Yoshio Nakatani ◽  
Helen K. Opel-Reading ◽  
Matthias Merker ◽  
Diana Machado ◽  
Sönke Andres ◽  
...  

ABSTRACT A screening of more than 1,500 drug-resistant strains of Mycobacterium tuberculosis revealed evolutionary patterns characteristic of positive selection for three alanine racemase (Alr) mutations. We investigated these mutations using molecular modeling, in vitro MIC testing, as well as direct measurements of enzymatic activity, which demonstrated that these mutations likely confer resistance to d-cycloserine.


Sign in / Sign up

Export Citation Format

Share Document