scholarly journals In Vitro Activities of Tritrpticin Alone and in Combination with Other Antimicrobial Agents against Pseudomonas aeruginosa

2006 ◽  
Vol 50 (11) ◽  
pp. 3923-3925 ◽  
Author(s):  
Oscar Cirioni ◽  
Andrea Giacometti ◽  
Carmela Silvestri ◽  
Agnese Della Vittoria ◽  
Alberto Licci ◽  
...  

ABSTRACT The in vitro activity of the cathelicidin tritrpticin was investigated against multidrug-resistant Pseudomonas aeruginosa. The isolates were susceptible to the peptide at concentrations of 0.50 to 8 mg/liter. Tritrpticin completely inhibits lipopolysaccharide procoagulant activity at a 10 μM concentration. Fractionary inhibitory concentration indexes (0.385, 0.312, and 0.458) demonstrated synergy between the peptide and β-lactams.

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S577-S577
Author(s):  
Cristhian Hernández-Gómez ◽  
Elsa De La Cadena ◽  
Maria F Mojica ◽  
Adriana Correa ◽  
Marcela Perengüez ◽  
...  

Abstract Background Multidrug-resistant Enterobacteriaceae (Ent) and Pseudomonas aeruginosa (Pae) are involved in a considerable number of healthcare-associated infections, thus representing a therapeutic challenge. Ceftolozane–tazobactam (C/T) is a combination of a novel cephalosporin with a known β-lactamase inhibitor. Ceftolozane has high affinity for penicillin-binding proteins, improved outer membrane permeability, increased stability against efflux and enhanced stability against chromosomal AmpC β-lactamases compared with other β-lactam antibiotics. This agent is not active against carbapenemases. We evaluated the in vitro activity of C/T against clinical isolates of Ent and Pae collected from 2016- 2017 and compared it to the activity of broad-spectrum antimicrobial agents. Methods 1.644 Ent and Pae non-duplicate clinical isolates were collected in 13 medical centers located in 12 Colombian cities. Minimum inhibitory concentrations (MIC) were performed by broth microdilution and interpreted according to current CLSI guidelines. Isolates tested included 813 Escherichia coli (Eco), 441 Klebsiella pneumoniae (Kpn), 82 Enterobacter spp., (Enb); 60 Serratia marcescens (Sma) and 248 Pae. Comparator agents were ceftriaxone (CRO), cefotaxime (CTX), ceftazidime (CAZ), cefepime (FEP), piperacillin/tazobactam (TZP), ertapenem (ETP), imipenem (IMI), meropenem (MEM). Results Susceptibilities to C/T and comparators of 4 Ent species and Pae are shown in Table 1. Compared with other β-lactams such as CRO, CAZ, TZP, and FEP, C/T had considerably higher susceptibility rates against ESBL, non-carbapenem-resistant (CR) Eco and Kpn isolates. C/T MIC50/90 were: Eco (≤1/≤1); Kpn (≤1/128); Enb (≤1/64); Sma (≤1/≥256); Pae (≤1/≥256). In the case of P.aeruginosa despite the high resistance rates observed in the study, C/T had the best susceptibility, even higher than the carbapenems. Conclusion Overall, C/T demonstrated higher in vitro activity than currently available cephalosporins and TZP when tested against Ent and Pae. C/T provides an important treatment option against infections caused by non-carbapenemase producing Gram-negative pathogens. Further studies are warranted to identify an emerging mechanism of resistance in Colombia. Disclosures All authors: No reported disclosures.


2005 ◽  
Vol 49 (6) ◽  
pp. 2510-2511 ◽  
Author(s):  
Yunhua Chen ◽  
Elizabeth Garber ◽  
Qiuqu Zhao ◽  
Yigong Ge ◽  
Matthew A. Wikler ◽  
...  

ABSTRACT Doripenem 50% inhibitory concentrations (MIC50) and 90% inhibitory concentrations (MIC90) for multidrug-resistant strains of mucoid Pseudomonas aeruginosa (n = 200 strains), nonmucoid P. aeruginosa (n = 200), and Burkholderia cepacia complex (n = 200) isolated from patients with cystic fibrosis were 8 and 32, 8 and 64, and 8 and 32 μg/ml, respectively. Doripenem had somewhat better activity than established antimicrobial agents.


1988 ◽  
Vol 8 (4) ◽  
pp. 277-279
Author(s):  
Wendy L. Vaudry ◽  
Claudia Gratton ◽  
Kinga Kowalewska ◽  
Wanda M. Wenman

The minimum inhibitory concentration (MIC) of daptomycin was compared with that of four other antimicrobial agents against clinically relevant staphylococci. Sixtyfive isolates were obtained from patients on continuous ambulatory peritoneal dialysis (CAPD) who contracted peritonitis. These isolates comprised 29 S. Sureus strains (all sensitive to oxacillin); 25 S. epidermidis strains (14 sensitive and 9 resistant to oxacillin); and 11 unspeciated coagulase-negative staphylococci (2 sensitive and 11 resistant to oxacillin). All of the oxacillin susceptible strains were inhibited by ≤2 mg/L of the five antibiotics tested. The oxacillin resistant staphylococci were also resistant to cefuroxime and variably resistant to cefamandole, but were uniformly susceptible to both vancomycin and daptomycin. Daptomycin possesses equivalent in vitro activity to vancomycin against strains of S. Sureus and coagulase negative staphylococci associated with CAPD peritonitis. If vancomycin resistance becomes a significant problem in these patients, and daptomycin is shown to be active against vancomycin resistant organisms, then it would have potential usefulness as an alternative to vancomycin in the treatment of peritonitis caused by multiply -resistant staphylococci.


2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S372-S372
Author(s):  
Andrew Walkty ◽  
Heather J Adam ◽  
Melanie Baxter ◽  
Philippe Lagace-Wiens ◽  
James Karlowsky ◽  
...  

Abstract Background Ceftolozane-tazobactam (C/T) is a novel β-lactam β-lactamase inhibitor combination with a broad spectrum of activity that includes Pseudomonas aeruginosa. The purpose of this study was to evaluate the in vitro activity of C/T and relevant comparators vs. a large collection of antimicrobial non-susceptible (NS) P. aeruginosa clinical isolates obtained from patients across Canada (CANWARD, 2008–2016). Methods From January 2008 to December 2016, inclusive, 12 to 15 sentinel hospitals across Canada submitted clinical isolates from patients attending ERs, medical and surgical wards, hospital clinics, and ICUs (CANWARD). Each center was asked to annually submit clinical isolates (consecutive, one per patient/infection site) from blood, respiratory, urine, and wound infections. Susceptibility testing was performed using broth microdilution as described by CLSI. Multidrug-resistant (MDR) P. aeruginosa were defined as isolates that tested NS to at least one antimicrobial from ≥3 classes. Extensively drug-resistant (XDR) P. aeruginosa were defined as isolates that tested NS to at least one antimicrobial from ≥5 classes. Results 3229 P. aeruginosa isolates were obtained as a part of CANWARD. The in vitro activity of C/T and relevant comparators is presented below. Conclusion C/T demonstrated excellent in vitro activity vs. antimicrobial NS P. aeruginosa clinical isolates, including MDR, XDR, and meropenem NS subsets. It may prove useful in the treatment of infections caused by these organisms. Disclosures D. Hoban, Abbott: Research relationship, Research support Achaogen: Research relationship, Research support Astellas: Research relationship, Research support Merck Canada: Research relationship, Research support Merck USA: Research relationship, Research support Paratek Pharma: Research relationship, Research support Pharmascience: Research relationship, Research support Sunovion: Research relationship, Research support Tetraphase: Research relationship, Research support The Medicines Co.: Research relationship, Research support Zoetis: Research relationship, Research support; G. Zhanel, Achaogen: Research relationship, Research support Astellas: Research relationship, Research support Merck Canada: Research relationship, Research support Merck USA: Research relationship, Research support Paratek Pharma: Research relationship, Research support Pharmascience: Research relationship, Research support Sunovion: Research relationship, Research support Tetraphase: Research relationship, Research support The Medicines Co.: Research relationship, Research support Zoetis: Research relationship, Research support


Antibiotics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 885
Author(s):  
Soraya Herrera-Espejo ◽  
Tania Cebrero-Cangueiro ◽  
Gema Labrador-Herrera ◽  
Jerónimo Pachón ◽  
María Eugenia Pachón-Ibáñez ◽  
...  

Multidrug-resistant (MDR) Pseudomonas aeruginosa is a public health problem causing both community and hospital-acquired infections, and thus the development of new therapies for these infections is critical. The objective of this study was to analyze in vitro the activity of pentamidine as adjuvant in combinations to antibiotics against seven clinical P. aeruginosa strains. The Minimum Inhibitory Concentration (MIC) was determined following standard protocols, and the results were interpreted according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints; however, the gentamicin activity was interpreted according to the Clinical and Laboratory Standards Institute (CLSI) recommendations. The bactericidal in vitro activity was studied at 1×MIC concentrations by time–kill curves, and also performed in three selected strains at 1/2×MIC of pentamidine. All studies were performed in triplicate. The pentamidine MIC range was 400–1600 μg/mL. Four of the strains were MDR, and the other three were resistant to two antibiotic families. The combinations of pentamidine at 1×MIC showed synergistic activity against all the tested strains, except for pentamidine plus colistin. Pentamidine plus imipenem and meropenem were the combinations that showed synergistic activity against the most strains. At 1/2×MIC, pentamidine plus antibiotics were synergistic with all three analyzed strains. In summary, pentamidine in combination with antibiotics showed in vitro synergy against multidrug-resistant P. aeruginosa clinical strains, which suggests its possible use as adjuvant to antibiotics for the therapy of infections from MDR P. aeruginosa.


2013 ◽  
Vol 46 (3) ◽  
pp. 299-303 ◽  
Author(s):  
Denissani Aparecida Ferrari dos Santos Lima ◽  
Margarida Maria Passeri do Nascimento ◽  
Lucia Helena Vitali ◽  
Roberto Martinez

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