Search

To determine the incidence and impact of Aspergillusspp. isolation (AI) on ICU mortality in critically ill patients with severe influenza pneumonia during the first 24h of admission.

ABSTRACTClinical breakpoints (CBPs) and epidemiological cutoff values (ECVs) have been established for several Candidaspp. and the newer triazoles and echinocandins but are not yet available for older antifungal agents, such as amphotericin B, flucytosine, or itraconazole. We determined species-specific ECVs for amphotericin B (AMB), flucytosine (FC) and itraconazole (ITR) for eight Candidaspp. (30,221 strains) using isolates from 16 different laboratories in Brazil, Canada, Europe, and the United States, all tested by the CLSI reference microdilution method. The calculated 24- and 48-h ECVs expressed in µg/ml (and the percentages of isolates that had MICs less than or equal to the ECV) for AMB, FC, and ITR, respectively, were 2 (99.8)/2 (99.2), 0.5 (94.2)/1 (91.4), and 0.12 (95.0)/0.12 (92.9) for C. albicans; 2 (99.6)/2 (98.7), 0.5 (98.0)/0.5 (97.5), and 2 (95.2)/4 (93.5) for C. glabrata; 2 (99.7)/2 (97.3), 0.5 (98.7)/0.5 (97.8), and 05. (99.7)/0.5 (98.5) for C. parapsilosis; 2 (99.8)/2 (99.2), 0.5 (93.0)/1 (90.5), and 0.5 (97.8)/0.5 (93.9) for C. tropicalis; 2 (99.3)/4 (100.0), 32 (99.4)/32 (99.3), and 1 (99.0)/2 (100.0) for C. krusei; 2 (100.0)/4 (100.0), 0.5 (95.3)/1 (92.9), and 0.5 (95.8)/0.5 (98.1) for C. lusitaniae; -/2 (100.0), 0.5 (98.8)/0.5 (97.7), and 0.25 (97.6)/0.25 (96.9) for C. dubliniensis; and 2 (100.0)/2 (100.0), 1 (92.7)/-, and 1 (100.0)/2 (100.0) for C. guilliermondii. In the absence of species-specific CBP values, these wild-type (WT) MIC distributions and ECVs will be useful for monitoring the emergence of reduced susceptibility to these well-established antifungal agents.

ABSTRACTAnidulafungin Etest and CLSI MICs were compared for 143 Candidasp. isolates to assess essential (within 2 log2dilutions) and categorical agreements (according to three susceptibility breakpoints). Based on agreement percentages, our data indicated that Etest is not suitable to test anidulafungin against Candida parapsilosisand C. guilliermondii(54.4 to 82.4% essential and categorical agreements) but is more suitable for C. albicans, C. glabrata, C. krusei, and C. tropicalis(87.9 to 100% categorical agreement).

ABSTRACTWe evaluated the performance of the 24-h broth microdilution voriconazole MIC by obtaining MICs for 2,162 clinical isolates of Candidaspp. and other yeasts; the 24-h results were compared to 48-h reference MICs to assess essential, as well as categorical, agreement. Although the overall essential agreement was 88.6%, it ranged from 96.4 to 100% for 6 of the 11 species or groups of yeasts tested. The overall categorical agreement was 93.2%, and it was above 90% for eight species. However, unacceptable percentages of very major errors (false susceptibility) were observed for Candida albicans(2.7%), C. glabrata(4.1%), C. tropicalis(9.7%), and other less common yeast species (9.8%). Since it is essential to identify potentially resistant isolates and breakpoints are based on 48-h MICs, it appears that the 24-h MIC is not as clinically useful as the 48-h reference MIC. However, further characterization of these falsely susceptible MICs for three of the four common Candidaspp. is needed to understand whether these errors are due to trailing misinterpretation or if the 48-h incubation is required to detect voriconazole resistance. Either in vivo versus in vitro correlations or the determination of resistance mechanisms should be investigated.

The intraphagocytic killing of Escherichia coli, Serratia marcescens, Pseudomonas aeruginosa,and Salmonella typhiby ciprofloxacin (0.1, 1 and 5 μg/ml) within human neutrophils with intact and impaired (by phenylbutazone treatment) O2-dependent killing mechanisms was studied and compared with the extracellular killing in the same medium of the intraphagocytic killing, but omitting neutrophils. The MIC/MBC of ciprofloxacin in vitro (assays performed according to NCCLS specifications) were: 0.015/0.06 for E. coli,0.12/32 for S. marcescens,1/16 for P. aeruginosa,and 0.007/0.06 for S. typhi.Ciprofloxacin showed bactericidal activity both extracellular and within phenylbutazone-treated and untreated neutrophils. The minimum concentration of ciprofloxacin to kill 90% of phagocytosed bacteria within neutrophils with normal O2-dependent killing power after 30 min was: 0.1 μg/ml for E. coli,and S. typhi,1 μg/ml for P. aeruginosa,and 5 μg/ml for S. marcescens.In contrast, exposure for 60 min was required to reach this percentage within phenylbutazone treated neutrophils. The minimum concentration to kill 90% of extracellular bacteria after 30 min was: 0.1 μg/ml for E. coli, P. aeruginosaand S. typhi,and 5 μg/ml, for S. marcescens.A positive interaction between ciprofloxacin and the O2-dependent mechanisms of phagocytes was found. The reactive oxygen metabolites produced in the respiratory burst did not affect the intraphagocytic activity of ciprofloxacin. Phenylbutazone treatment of phagocytes would be a good experimental model to study the intraphagocytic killing of drugs in situations such as AIDS and chronic granulomatous disease where inefficient oxidative mechanisms of neutrophils exist.

ABSTRACTWhen evaluated in six clinical laboratories from six countries with 1,174 fresh isolates, including 715 Candida glabrataand 459 non-C. glabratastrains, GLABRATA RTT (Fumouze Diagnostics, Levallois Perret, France) yielded an overall sensitivity and an overall specificity of 95.8 and 98.9%, respectively. The results were consistent from one laboratory to another. The five false-positive results corresponded to C. parapsilosis(n= 2), C. tropicalis, C. guilliermondii, and C. lusitaniae.GLABRATA RTT allows a rapid, cost-effective, and reliable presumptive identification of C. glabrata.

Although the Sensititre Yeast-One (SYO) and Etest methods are widely utilized, interpretive criteria are not available for triazole susceptibility testing of Candidaor Aspergillusspecies. We collected fluconazole, itraconazole, posaconazole, and voriconazole SYO and Etest MICs from 39 laboratories representing all continents for (method/agent-dependent) 11,171 Candida albicans, 215 C. dubliniensis, 4,418 C. glabrataspecies complex, 157 C.guilliermondii(Meyerozyma guilliermondii), 676 C. krusei(Pichia kudriavzevii), 298 C.lusitaniae(Clavispora lusitaniae), 911 C.parapsilosissensu stricto, 3,691 C.parapsilosisspecies complex, 36 C.metapsilosis, 110 C.orthopsilosis, 1,854 C.tropicalis, 244 Saccharomyces cerevisiae, 1,409 Aspergillus fumigatus, 389 A.flavus, 130 A.nidulans, 233 A.niger, and 302 A.terreuscomplex isolates.