Montoya Alexandra M, Elizondo-Zertuche Mariana, Treviño-Rangel Rogelio de J, Becerril-García Miguel, González Gloria M
Departamento de Microbiología, Facultad de Medicina, Universidad Autónoma de Nuevo León, Mexico.
Departamento de Microbiología, Facultad de Medicina, Universidad Autónoma de Nuevo León, Mexico.
Rev Iberoam Micol. 2018 Jan-Mar;35(1):22-26. doi: 10.1016/j.riam.2017.02.008. Epub 2017 Dec 26.
Trichosporon asahii is a yeast-like fungus that has recently gained importance as a cause of opportunistic systemic infections. The pathogenicity and virulence factors of T. asahii remain largely unknown. Because of the association between invasive infections and the use of catheters and related devices, the ability of the microorganism to adhere and form biofilms may play an important role in the pathogenicity during a trichosporonosis.
The aim of this study is to identify an association between biofilm formation by T. asahii isolates and their genotype and/or clinical source.
The biofilm production of 49 T. asahii strains isolated from Mexican patients was measured using the crystal violet stain method, and a comparison made with different adhesion phase incubation times. Antifungal susceptibility testing was performed using a modified CLSI protocol coupled with the quantification of the viable cells with the XTT reduction method.
All the T. asahii isolates assayed were able to produce biofilm in vitro, with an intraspecific variability being observed. Overall, increased biofilm production was found when extending the adhesion phase incubation time from 2 to 4h. No association could be established between the biofilm-producing phenotype and either the genotype or clinical source. Higher antifungal resistance to amphotericin B and fluconazole was linked to increased biofilm production by T. asahii.
All clinical isolates tested were able to produce biofilm. No association could be established between biofilm formation and genotype or clinical source.
浅黄丝孢酵母是一种酵母样真菌，最近作为机会性全身感染的病原体而受到关注。浅黄丝孢酵母的致病性和毒力因子在很大程度上仍不清楚。由于侵袭性感染与导管及相关装置的使用之间存在关联，该微生物粘附并形成生物膜的能力可能在丝孢酵母病发病过程的致病性中起重要作用。
本研究旨在确定浅黄丝孢酵母分离株形成生物膜与其基因型和/或临床来源之间的关联。
采用结晶紫染色法测定从墨西哥患者分离出的49株浅黄丝孢酵母菌株的生物膜产生情况，并比较不同粘附期孵育时间的结果。使用改良的CLSI方案进行抗真菌药敏试验，并采用XTT还原法对活细胞进行定量。
所有检测的浅黄丝孢酵母分离株均能在体外产生生物膜，且观察到种内变异性。总体而言，将粘附期孵育时间从2小时延长至4小时可使生物膜产生增加。生物膜产生表型与基因型或临床来源之间未发现关联。浅黄丝孢酵母对两性霉素B和氟康唑的更高耐药性与生物膜产生增加有关。
所有检测的临床分离株均能产生生物膜。生物膜形成与基因型或临床来源之间未发现关联。
