METHODS: We inoculated pure isolates of Rhizopus arrhizus obtained from subjects with CAM on dichloran rose Bengal chloramphenicol (DRBC) agar enriched with (three different concentrations) and without zinc. At 24 h, we counted the viable colonies and measured the dry weight of colonies at 24, 48 and 72 h. We also compared the clinical features and serum zinc levels in 29 CAM cases and 28 COVID-19 subjects without mucormycosis (controls).
RESULTS: We tested eight isolates of R arrhizus and noted a visible increase in growth in zinc-enriched media. A viable count percentage showed a significantly increased growth in four of the eight isolates in zinc-augmented DRBC agar. A time- and concentration-dependent increase in the mean fungal biomass with zinc was observed in all three isolates tested. We enrolled 29 cases of CAM and 28 controls. The mean serum zinc concentration was below the reference range in all the subjects and was not significantly different between the cases and controls.
CONCLUSIONS: Half of the R arrhizus isolates grew better with zinc enrichment in vitro. However, our study does not conclusively support the hypothesis that zinc supplementation contributed to the pathogenesis of mucormycosis. More data, both in vitro and in vivo, may resolve the role of zinc in the pathogenesis of CAM.
方法:我们在富含(三种不同浓度)和不含锌的二氯玫瑰红氯霉素(DRBC)琼脂上接种了CAM从受试者获得的阿根根霉的纯分离株。在24小时,我们在24、48和72h计算了活菌落并测量了菌落的干重。我们还比较了29例CAM病例和28例无毛霉菌病的COVID-19受试者(对照组)的临床特征和血清锌水平。
结果:我们测试了八种arrhizus分离株,并注意到在富含锌的培养基中生长明显增加。活菌数百分比显示,在锌增强的DRBC琼脂中,八个分离物中的四个分离物中的生长显着增加。在所有三个测试的分离物中观察到平均真菌生物量随锌的时间和浓度依赖性增加。我们招募了29例CAM和28例对照。在所有受试者中,平均血清锌浓度均低于参考范围,并且在病例和对照组之间没有显着差异。
结论:在体外锌富集的情况下,一半的Rarrhizus分离株生长更好。然而,我们的研究并不最终支持锌补充有助于毛霉菌病发病机制的假设.更多数据,在体外和体内,可能解决锌在CAM发病机制中的作用。