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Background: Candida dubliniensis is a recently described Candida species closely related to Candida albicans, which has been associated with oral candidiasis in HIV-infected patients. Fluconazole-resistant strains of C. dubliniensis are easily obtained in vitro and this fact could be a complication if this resistance develops during treatment with this drug. Methods: In the present study, the in vitro antifungal susceptibilities of 36 C. dubliniensis clinical isolates and culture strains to current and new antifungal agents, such as amphotericin B (AMB), amphotericin B lipid complex (ABLC), amphotericin B colloidal dispersion (ABCD), 5-fluorocytosine (5FC), fluconazole (FLC), itraconazole (ITC), ketoconazole (KTC), liposomal amphoteri- cin B (LAMB), liposomal nystatin (LNYT), LY303366 (LY), SCH56592 (SCH), and voriconazole (VRC), were determined according to the National Committee for Clinical Laboratory Standards M27-A broth microdilution method for yeasts. Results: Most isolates of C. dubliniensis were susceptible to both new and current antifungal drugs, with 75.9% isolates susceptible to KTC, 86.2% to FLC and to ITC, and ∼100% to the other antifungal agents tested. The cross-resistance phenotypes are detailed. Four isolates were resistant (MIC ≥64 μg/ml) to FLC. These 4 isolates were also resistant to KTC, and 3 of them were also resistant to ITC (MIC ≥1 μg/ml for both agents). However, these isolates were highly susceptible to 5FC and all polyene formulations (AMB, ABLC, ABCD, LAMB, and LNYT), triazole (SCH and VRC) and echinocandin (LY) antifungal agents. Conclusion: The new liposomal and lipidic formulations of AMB, LNYT, and the new triazoles and echinocandins may provide new alternatives to FLC for the treatment of infections by C. dubliniensis.

This study further evaluated the in vitro activity of anidulafungin (VER002, Versicor Inc.) (LY303366) against 460 clinical yeast isolates. MICs of anidulafungin, fluconazole and itraconazole were determined by following the NCCLS M27-A guidelines. Minimum fungicidal concentrations (MFCs) of anidulafungin were determined for 230 isolates of Candida spp. The activity of anidulafungin in vitro was significantly superior (P < 0.05) to those of itraconazole and fluconazole against Candida albicans, Candida tropicalis, Candida glabrata and Candida krusei, but anidulafungin was less active for Candida famata and Candida parapsilosis. The differences were not significant for the other species evaluated.

Amphotericin B (AMB) is considered the gold standard in the treatment of serious systemic mycoses in spite of its nephrotoxicity and adverse effects. Association with lipids enables larger doses of AMB to be given with a longer t_½ and C_max, without the toxic effects at lower concentrations. Liposome-encapsulated AMB shows a lower affinity for mammalian cells and improves V_d, thus decreasing toxicity. Amphotericin B lipid complex (ABLC) is an AMB formulation associated with a biodegradable phospholipid matrix (5% molar) from which the drug is released by cell phospholipases. ABLC is recommended for serious mycoses refractory to conventional antifungal therapy or when AMB is contraindicated. We compared the in vitro antifungal activity of ABLC, AMB and fluconazole (FLZ) against 328 strains of clinically significant opportunistic fungi using a microdilution method (NCCLS, M-27A). 64.9% of the yeasts were inhibited by MIC of ABLC ≤ AMB resulting in a similar or slightly superior efficacy compared to AMB when tested against Candida albicans, C. glabrata, C. guilliermondii, C. parapsilosis and C. tropicalis. Effectiveness against C. krusei was lower for ABLC (5.99 μg/ml for ABLC, 1.58 μg/ml for AMB). However, for Aspergillus fumigatus, the activities of AMB and ABLC were 1.62 and 2.46 μg/ml, respectively; A. niger 0.72 μg/ml, 0.76 μg/ml (ABLC and AMB, respectively); A. clavatus, A. candidus, A. tenuissima, A. corymbifera and Exophiala jeanselmei, Scedosporium spp. and Miceliophtora spp. showed a low susceptibility to both AMB formulations. ABLC is a useful alternative to AMB or FLZ for the treatment of severe fungal infections, due to the broad spectrum of antifungal actions observed in this study.

To determine the prevalence of Salmonella enterica serotypes in imported frozen chicken meat, 406 samples (whole chicken, legs, and breast meat) were analyzed for Salmonella according to ISO6579 rules, serotypes were assigned, and phage typing was conducted for Salmonella serotypes Enteritidis, Typhimurium, and Heidelberg. The overall frequency of Salmonella isolation was 16.5%. By country of origin, the highest percentage of cases was found among the samples from France followed by samples from Brazil. The differences between legs and breast meat were significant. The most frequently isolated serotype of Salmonella was Enteritidis, followed by Salmonella Heidelberg, Salmonella Typhimurium, and Salmonella Virchow. By country of origin, we identified a large percentage of serotype Salmonella Enteritidis in the samples imported from Brazil. There was a greater diversity of serotypes isolated from the French samples, and Salmonella Enteritidis was not the dominant strain. In the samples from the United States, the only serotype isolated was Salmonella Kentucky, although a smaller number of samples was analyzed. The Salmonella Enteritidis phage type that prevailed in both France and Brazil was 4. Phage types 204c and 204 were identified for Salmonella Typhimurium, and phage types 8, 31, and 37 were identified for Salmonella Virchow.