Otimização da rotina de hemoculturas positivas para Candida spp. : identificação pelo sistema automatizado MALDI-TOF VITEK MS ® determinação do perfil de sensibilidade diretamente do frasco de hemocultura

Resumo não disponível

Identificação e determinação do perfil de sensibilidade de forma rápida de Candida spp. isoladas de hemoculturas

Base Teórica: As infecções de corrente sanguínea causadas por espécies Candida têm aumentado e tornaram-se prevalentes com taxas de mortalidade próximas ou superiores a 50%. O início tardio da farmacoterapia adequada se correlaciona com um aumento da taxa de mortalidade e por esse motivo a rápida identificação das espécies e a determinação do seu perfil de sensibilidade são fundamentais para orientá-la, reduzir custos e tempo de internação. O MALDI-TOF é uma tecnologia que permite a identificação rápida e confiável de patógenos e pode auxiliar na agilidade desses resultados. Objetivo: Desenvolver um método rápido, prático e barato para a identificação e determinação do perfil de sensibilidade ao Fluconazol e Micafungina para Candida spp. isoladas de hemocultura. Metodologia: Identificação por MALDI-TOF e determinação do perfil de sensibilidade Candida spp. por microdiluição em caldo, diretamente do frasco de hemocultura positiva, após subcultivo e incubação por cerca de 5 horas, de amostras pacientes internados no Hospital de Clínicas de Porto Alegre entre 2019 e 2020. Resultados: Os testes diretamente do frasco permitiriam a obtenção dos resultados entre 24 a 48 horas antes do método padrão. Os resultados da identificação rápida obtiveram uma concordância categórica de 92,05% (220 em 239 amostras clínicas), comparado ao método padrão. Quando avaliado por espécie, C. glabrata e C. krusei, obtiveram 100% de concordância. Na microdiluição rápida para o Fluconazol a concordância foi de 97,06% (p< 0,001), o índice de concordância Kappa foi de aproximadamente 0,91 (p< 0,001), apresentou um erro menor (1,47%) e um erro maior (1,47%). Já na microdiluição rápida para a Micafungina não houve erros, obtendo concordância de 100% (p< 0,001) e o índice Kappa de 1,0 (p< 0,001). Conclusão: As metodologias rápidas para identificação e determinação do perfil de sensibilidade de Candida spp. são uma ótima alternativa aos métodos utilizados atualmente na rotina do laboratório de microbiologia. Além dessas metodologias serem eficazes, reprodutíveis, baratas e de fácil execução, são confiáveis e possibilitam a liberação do resultado de forma precoce impactando diretamente na eficácia do tratamento.Background: Bloodstream infections caused by Candida species have increased and become prevalent with mortality rates close to 50%. The late start of adequate pharmacotherapy is correlated with an increase in the mortality rate and, for this reason, the rapid identification of the species and the determination of their susceptibility profile are essential to guide it, reduce costs and hospitalization time. MALDI-TOF is a technology that allows fast and reliable identification of pathogens and can help speed up these results. Objective: Develop a rapid, practical, and inexpensive method for identification and determination of the susceptibility profile to Fluconazole and Micafungin of Candida spp. isolated from blood culture. Methods: Identification through MALDI-TOF and determination of susceptible profile through broth microdilution, directly from the positive blood culture bottles after subculture and short-term incubation of Candida sp. samples from patients admitted to Hospital de Clínicas de Porto Alegre between 2019 and 2020. Results: Tests directly from the bottle would allow obtaining results 24 to 48 hours before the standard method. The rapid identification results obtained a categorical agreement of 92.05% (220 out of 239 clinical samples) compared to the standard method. Regarding species identification, C.glabrata and C. krusei obtained 100% agreement. In rapid broth microdilution for Fluconazole, the agreement was 97.06% (p<0.001), the Kappa agreement coefficient was approximately 0.91 (p<0.001), had a minor error (1.47%) and a major error (1.47%). In the rapid broth microdilution for Micafungin, there were no errors, obtaining 100% agreement (p<0.001) and the Kappa coefficient was 1.0 (p<0.001). Conclusion: Rapid methodology for identifying and determining the susceptibility profile of Candida spp. is an excellent alternative to the methods currently used in the routine of the microbiology laboratory. In addition to these methodologies are efficient, reproducible, inexpensive, and easy to perform, they are reliable and release of the result early, directly impacting effectiveness of the treatment

Evaluation of identification and susceptibility for Candida spp. isolated directly from positive blood culture bottles

Determination of the susceptibility profile of isolates of Candida from blood culture bottles is extremely important for correctly guiding patient pharmacotherapy. ,e aim of this study was to compare the results of analysis of Candida isolated directly from blood culture bottles by the VITEK MS MALDI-TOF identification system and the fluconazole disk diffusion assay with those of standard identification methods. Testing directly from the bottle allowed results 24 to 48 hours quicker than the standard method. ,ere was a categorical agreement of 51.64% (47 of 91 samples) between the results of analysis directly from the bottle and analysis by the standard method. Regarding species identification, there was 96.15% agreement for Candida parapsilosis (25 of 26 samples). Categorical agreement between the rapid and standard disk diffusion methods was 95%, and the agreement between the rapid disk diffusion method and the broth microdilution method was 97%. Only minor errors in the rapid method were observed: 3 (5%) in the standard disk diffusion method and 2 (3%) in the broth microdilution method. Our study concluded that the rapid disk diffusion method for fluconazole is a fast, easy, reproducible, and consistent method. Its timely implementation for testing antifungal agents in the clinical microbiology laboratory can help reduce profile release times, thus helping to determine the most appropriate antifungal treatment

Otimização da rotina de hemoculturas positivas para Candida spp. : identificação pelo sistema automatizado MALDI-TOF VITEK MS ® determinação do perfil de sensibilidade diretamente do frasco de hemocultura

Resumo não disponível

Rapid bacterial identification by MALDI-TOF MS directly from blood cultures and rapid susceptibility testing: A simple approach to reduce the turnaround time of blood cultures

Antimicrobial treatment of patients with bloodstream infections (BSI) is time-sensitive. In an era of increasing antimicrobial resistance, rapid detection and identification of bacteria with antimicrobial susceptibility are critical for targeted therapy early in the disease course. This study describes the performance of a rapid method for identifying and testing antimicrobial susceptibility of Gram-negative bacteria performed directly from blood culture bottles in a routine microbiology laboratory. A total of 284, 120, and 24 samples were analyzed by rapid identification (Rid), rapid susceptibility testing (RAST), and rapid broth microdilution for polymyxin B (rMIC), respectively, and compared with standard methods. Our protocol was able to identify 93% of isolates at the species level using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). We obtained 100% agreement for RAST compared to the standard method and 96% agreement for rMIC. Our protocol has proven to be an excellent tool for rapid identification of Gram-negative bacilli causing BSIs. It can also be used in microbiology laboratory routine along with RAST and faster polymyxin microdilution, especially for carbapenemase-producing bacteria, allowing for rapid, simple, accurate, and cost-effective diagnosis