Ebru Evren

In vitro activity of fosfomycin in combination with imipenem, meropenem, colistin and tigecycline against OXA 48–positive Klebsiella pneumoniae strains ☆ ☆☆

Carbapenem resistance due to OXA-48 enzymes in Klebsiella pneumoniae is increasing particularly in the Middle Eastern and European regions. Treatment options are limited. The aim of this study was to evaluate the in vitro synergistic activity of fosfomycin in combination with imipenem, meropenem, colistin and tigecycline against OXA-48 producing K. pneumoniae strains. Twelve carbapenem-resistant OXA-48 producing K. pneumoniae isolates were enrolled in this study. Synergistic activity of fosfomycin combined with imipenem, meropenem, colistin, and tigecycline was assessed by chequerboard method. The combination of fosfomycin was synergistic with imipenem, meropenem and tigecycline with the ratios of 42%, 33%, and 33%, respectively. Whilst the combination of fosfomycin with colistin was fully antagonistic against all of the strains, there was no statistically significant difference between the in vitro synergistic activities of fosfomycin in combination with imipenem, meropenem and tigecycline combinations (P > 0.05). Fosfomycin in combination with other agents can be preferred against multidrug resistant K. pneumoniae strains.

Efficacy of multipurpose contact lens solutions against ESBL-positive Escherichia coli, MRSA, and Candida albicans clinical isolates.

Objectives: The antimicrobial effects of multipurpose contact lens solutions (MPSs) have been evaluated according to ISO 14729 standards. The aim of this study was to assess the efficacy of commercially available MPSs against extended-spectrum beta lactamases (ESBL)-producing Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans clinical isolates. Methods: Three commercially available contact lens solutions (Opti-Free Expresss, ReNu MultiPlus, and Solo Care Aqua) were tested against 18 ESBL-positive E. coli clinical strains, 20 MRSA clinical strains, and 20 C. albicans clinical strains. The stand-alone assays for bacteria and fungi were performed according to ISO 14729 criteria, and all samples were evaluated after 2, 4, and 24 hours of incubation. The numbers of viable microorganisms were evaluated by the plate-counting method. Results: All MPSs demonstrated at least 3 log reduction in colony-forming units (CFU) for all bacterial isolates and 1 log reduction in CFU for all yeast isolates, which meets ISO 14729 standards. Although no statistically significant differences were obtained among MPSs for bacterial isolates, variable responses were observed against clinical isolates: 5% povidone–iodine was more effective compared with Solo Care Aqua for C. albicans clinical strains (P<0.05); and all solutions were effective after an incubation time of only 2 hrs. The MPSs showed good activity against S. aureus, E. coli, and C. albicans. Conclusions: Although effective log reductions were provided with all MPSs, the reduction was variable depending on the strains tested. Multipurpose contact lens solutions should be tested under ISO 14729 standards for both standard and clinical strains.

Değişik içeriklere sahip Castellani solüsyonunun farklı mikroorganizmalar üzerine in vitro etkinliği

Objective: As the external auditory canal is a moisture area, it facilitates the growth of bacteria and fungi. Infections and inflammation due to Staphylococcus aureus, Pseudomonas aeruginosa, Aspergillus spp. and Candida albicans can develop in this area. Classical Castellani solution including boric acid, fenol, fucsin, resorcinol, acetone, and alcohol is used for external ear tract infections due to fungi and bacteria, and also for the superficial der matophytoses, and eczematous dermatitis of the external ear tract infections. The purpose of this study is to investigate of the in vitro effectiveness of classical Castellani solution and its different formulations with different dilutions against the standard yeast and bacteria strains.