scholarly journals In Vitro Activities of Fluconazole and Voriconazole against Clinical Isolates of Candida spp. Determined by Disk Diffusion Testing in Turin, Italy

2009 ◽  
Vol 53 (4) ◽  
pp. 1657-1659 ◽  
Author(s):  
Narcisa Mandras ◽  
Vivian Tullio ◽  
Valeria Allizond ◽  
Daniela Scalas ◽  
Giuliana Banche ◽  
...  

ABSTRACT The in vitro activities of fluconazole and voriconazole against 1,024 clinical isolates of Candida spp. were determined by the agar disk diffusion test using the Clinical and Laboratory Standards Institute (CLSI) M44-A guidelines. The results of this investigation demonstrated the broad-spectrum in vitro activity of voriconazole, relative to that of fluconazole, against yeasts tested, in particular fluconazole-resistant isolates, such as Candida krusei that showed high susceptibility to voriconazole. The situation in Turin, Italy, is quite similar to that of the rest of Italy, reflecting the worldwide trend.

Chemotherapy ◽  
2009 ◽  
Vol 55 (1) ◽  
pp. 20-27 ◽  
Author(s):  
Liliana Fernández Canigia ◽  
Sara Kaufman ◽  
Liliana Lanata ◽  
Carlos Vay ◽  
Marta Giovanakis ◽  
...  

2011 ◽  
Vol 44 (3) ◽  
pp. 334-338 ◽  
Author(s):  
Aurean D'Eça Júnior ◽  
Anderson França Silva ◽  
Fernanda Costa Rosa ◽  
Sílvio Gomes Monteiro ◽  
Patrícia de Maria Silva Figueiredo ◽  
...  

INTRODUCTION: Candida yeasts are commensals; however, if the balance of normal flora is disrupted or the immune defenses are compromised, Candida species can cause disease manifestations. Several attributes contribute to the virulence and pathogenicity of Candida, including the production of extracellular hydrolytic enzymes, particularly phospholipase and proteinase. This study aimed to investigate the in vitro activity of phospholipases and acid proteinases in clinical isolates of Candida spp. METHODS: Eighty-two isolates from hospitalized patients collected from various sites of origin were analyzed. Phospholipase production was performed in egg yolk medium and the production of proteinase was verified in a medium containing bovine serum albumin. The study was performed in triplicate. RESULTS: Fifty-six (68.3%) of isolates tested were phospholipase positive and 16 (44.4%) were positive for proteinase activity. C. tropicalis was the species with the highest number of positive isolates for phospholipase (91.7%). Statistically significant differences were observed in relation to production of phospholipases among species (p<0,0001) and among the strains from different sites of origin (p=0.014). Regarding the production of acid protease, the isolates of C. parapsilosis tested presented a larger number of producers (69.2%). Among the species analyzed, the percentage of protease producing isolates did not differ statistically (χ2=1.9 p=0.5901 (χ2=1.9 p=0.5901). CONCLUSIONS: The majority of C. non-albicans and all C. albicans isolates were great producers of hydrolytic enzymes and, consequently, might be able to cause infection under favorable conditions.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S281-S281
Author(s):  
Andrew Walkty ◽  
James Karlowsky

Abstract Background There are limited options available for the treatment of infections caused by Enterobacteriaceae that produce an NDM metallo-β-lactamase. The purpose of this study was to compare the in vitro activity of aztreonam in combination with three different β-lactam/β-lactamase inhibitors (ceftazidime–avibactam, amoxicillin-clavulanate, piperacillin–tazobactam) vs. NDM-positive Enterobacteriaceae clinical isolates. Methods Seven Escherichia coli and three Klebsiella pneumoniae clinical isolates (all NDM-positive by PCR) were included in this study. The in vitro activities of ceftazidime–avibactam, amoxicillin-clavulanate, piperacillin–tazobactam, and aztreonam were determined by disk diffusion as described by CLSI. For synergy testing, disks containing a β-lactamase inhibitor (ceftazidime–avibactam, amoxicillin-clavulanate, piperacillin tazobactam) were applied to Mueller–Hinton agar plates inoculated with the test organisms, and the plates were incubated for 1 hour. The disks were then removed and aztreonam disks were dropped on the previous disk sites. The plates were then incubated as per standard CLSI recommendations for disk diffusion testing. Results All ten isolates demonstrated phenotypic resistance to aztreonam, amoxicillin-clavulanate, and piperacillin–tazobactam, and eight were resistant to ceftazidime–avibactam (CLSI breakpoints). The zone diameter observed for aztreonam in combination with ceftazidime–avibactam was greater than for either antimicrobial on its own for nine isolates. Seven isolates (70%) had susceptibility to aztreonam restored (zone diameter ≥21 mm) in the presence of avibactam. Aztreonam in combination with amoxicillin-clavulanate demonstrated in increase in zone diameter for all isolates relative to the zone for each antimicrobial alone, but only two (20%) had aztreonam susceptibility restored. Aztreonam susceptibility was not restored for any of the isolates in combination with piperacillin–tazobactam. Conclusion Of the three β-lactam/β-lactamase inhibitor-aztreonam combinations evaluated, ceftazidime–avibactam plus aztreonam demonstrated the greatest in vitro activity vs. NDM-producing Enterobacteriaceae. Disclosures All authors: No reported disclosures.


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