Infection and Drug Resistance (Aug 2023)
The in vitro Activity of Echinocandins Against Clinical Trichophyton rubrum Isolates and Review of the Susceptibility of T. rubrum to Echinocandins Worldwide
Abstract
Huilin Su,1– 3,* Weiwei Jiang,4,* Paul E Verweij,3,5 Li Li,2 Junhao Zhu,2 Jiande Han,1 Min Zhu,2 Shuwen Deng6 1Department of Dermatology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, People’s Republic of China; 3Department of Medical Microbiology and Center of Expertise in Mycology, Radboud University Medical Center, Nijmegen, the Netherlands; 4Department of Dermatology, Hospital affiliated to the 72nd Army of Chinese PLA, Huzhou, People’s Republic of China; 5Department of Medical Microbiology and Center of Expertise in Mycology, CWZ Hospital, Nijmegen, the Netherlands; 6Department of Medical Microbiology, The People’s Hospital of SND, Suzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Shuwen Deng, Department of Medical Microbiology, The People’s Hospital of SND, Suzhou, People’s Republic of China, Email [email protected] Min Zhu, Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, People’s Republic of China, Email [email protected]: The emergence of resistance in Trichophyton rubrum to azoles and terbinafine has become increasingly evident in recent years, necessitating the development of novel antifungal drugs and the exploration of new indications for existing agents.Methods: In this study, we retrospectively evaluated the in vitro antifungal activity of 3 echinocandins (anidulafungin, caspofungin, and micafungin) against 73 clinical isolates of T. rubrum collected from a teaching hospital in Shanghai, China, using EUCAST E.DEF 9.3.1 with minor modification. We also reviewed the susceptibility of T. rubrum to echinocandins globally by literature searching.Results: Our findings revealed that micafungin exhibited the lowest modal minimum effective concentration (MEC) value (0.08 mg/L, n = 28) and the lowest geometric mean (GM) MEC value (0.014 mg/L) among the 73 isolates of T. rubrum tested, followed by anidulafungin with a modal MEC value of 0.016 mg/L (n = 67) and a GM of 0.018 mg/L. Caspofungin displayed a higher modal MEC value of 0.5 mg/L (n = 35) and a GM of 0.308 mg/L. Despite variations in methodologies, similar results were obtained from the review of five relevant studies included in our analysis.Discussion: Echinocandins exhibited excellent in vitro activity against T. rubrum isolates, with micafungin and anidulafungin demonstrating greater potency than caspofungin. These findings suggest that echinocandins could be considered as potential treatment options for managing recalcitrant dermatophytoses resulting from the emergence of resistance. However, it is important to note that the clinical efficacy of these in vitro findings has yet to be established and warrants further investigation.Keywords: echinocandins, Trichophyton rubrum, antifungal activity, review
