Antifungal activity of Taurolidine against Mucorales: An in vitro study on clinical isolates

Background and Purpose: Taurolidine is active against a wide variety of micro organisms, including bacteria and fungi. Mucormycosis is one of the life-threatening opportunistic fungal infections, especially in immunocompromised patients. Currently, the emergence of Mucormycosis during the COVID-۱۹ pandemic raises public health concerns regarding untoward morbidity and mortality among SARS-CoV-۲ patients. It is well-known that delayed and inappropriate antifungal therapy leads to increased morbidity and mortality. This study aimed to investigate the in-vitro antifungal activity of taurolidine to evaluate its effects against clinical isolates of Mucorales.Materials and Methods: This study included previously collected clinical Mucorales isolates. The minimum in vitro inhibitory concentration (MIC) of amphotericin B, caspofungin, voriconazole, posaconazole, and itraconazole was determined using the broth microdilution method.Results: All clinical isolates showed full sensitivity to amphotericin B. Posaconazole MIC range from ۸ μg/mL to ۰.۰۳۲ μg/mL. The MIC range of voriconazole and caspofungin were determined to be ۲-۸ µg/mL and ۰.۵-۱۶ µg/mL, respectively. Growth of the isolates was entirely inhibited in ۱۰۰۰ µg/mL concentration of taurolidine. In microscopic observations, morphological effects on hyphal growth were observed at ۵۰۰ µg/mL concentration.Conclusion: In conclusion, this is an updated experience of using taurolidine against Mucorales. However, our in-vitro findings need to be confirmed in well-designed clinical trials aimed at treating invasive Mucormycosis infections.

Keywords:

minimum inhibitory concentrations , Mucormycosis , Mucorales , taurolidine