Evaluating VITEK MS for the identification of clinically relevant Aspergillus species.

Aspergillus spp. identification has become more relevant in clinical practice since azole-resistant cryptic species have been related to invasive fungal infections. Conventional morphologic identification is not able to discriminate Aspergillus species, and DNA sequencing is not feasible for clinical laboratories. MALDI-TOF mass spectrometry is an emergent technology that has been explored to provide fast and accurate identification of microorganisms, including clinically relevant moulds. However, only a few studies have explored the platform VITEK MS for the identification of Aspergillus species. Hence, we provided additional data regarding the performance of the VITEK MS system for the identification of Aspergillus species, including azole-resistant ones. We also improved the RUO system by adding additional spectral profiles from well-identified Aspergillus strains belonging to different noncryptic and cryptic species. The IVD library correctly identified 91.6% of the organisms at genus and section level, and 84.7% at species level, including the azole-resistant Aspergillus lentulus and Aspergillus calidoustus. The organisms belonging to Aspergillus cryptic species had only 31.2% of correct species identification. The RUO library plus our in-house SuperSpectra correctly identified 100% of the organisms at genus and section level and 91.6% at species level. Among organisms belonging to Aspergillus cryptic species, 68.7% had correct species identification. Some closely related Aspergillus cryptic species showed similar spectral profiles and were difficult to be differentiated.

Performance of the Albicans ID2 FONT FACE=Symbol>Ò /FONT> chromogenic medium for rapid identification of Candida albicans

The aim of our study was to evaluate the accuracy of the chromogenic media Albicans ID2 FONT FACE=Symbol>Ò /FONT> (bioMérieux, France) for the identification of Candida albicans among 330 yeast strains. All C. albicans (100) and C. dubliniensis (20) strains exhibited blue color when cultured on Albicans ID2 FONT FACE=Symbol>Ò /FONT>. However, the blue color was also exhibited by cultures of C. rugosa (30/30) and C. tropicalis (3/50) isolates.

O objetivo do nosso estudo foi avaliar a eficácia do meio cromogênico Albicans ID2 FONT FACE=Symbol>Ò /FONT> (bioMérieux, France) na identificação de Candida albicans entre 330 amostras de leveduras. As cepas de C. albicans (100) e C. dubliniensis (20) exibiram coloração azul quando semeadas em Albicans ID2 FONT FACE=Symbol>Ò /FONT>. Contudo, a coloração azul também foi verificada em culturas de C. rugosa (30/30) e C. tropicalis (3/50).