Antifungal Susceptibility and Phylogeny of Opportunistic Members of the Order Mucorales
- 1 January 2012
- journal article
- Published by American Society for Microbiology in Journal of Clinical Microbiology
- Vol. 50 (1), 66-75
- https://doi.org/10.1128/jcm.06133-11
Abstract
The in vitro susceptibilities of 66 molecularly identified strains of the Mucorales to eight antifungals (amphotericin B, terbinafine, itraconazole, posaconazole, voriconazole, caspofungin, micafungin, and 5-fluorocytosine) were tested. Molecular phylogeny was reconstructed based on the nuclear ribosomal large subunit to reveal taxon-specific susceptibility profiles. The impressive phylogenetic diversity of the Mucorales was reflected in susceptibilities differing at family, genus, and species levels. Amphotericin B was the most active drug, though somewhat less against Rhizopus and Cunninghamella species. Posaconazole was the second most effective antifungal agent but showed reduced activity in Mucor and Cunninghamella strains, while voriconazole lacked in vitro activity for most strains. Genera attributed to the Mucoraceae exhibited a wide range of MICs for posaconazole, itraconazole, and terbinafine and included resistant strains. Cunninghamella also comprised strains resistant to all azoles tested but was fully susceptible to terbinafine. In contrast, the Lichtheimiaceae completely lacked strains with reduced susceptibility for these antifungals. Syncephalastrum species exhibited susceptibility profiles similar to those of the Lichtheimiaceae. Mucor species were more resistant to azoles than Rhizopus species. Species-specific responses were obtained for terbinafine where only Rhizopus arrhizus and Mucor circinelloides were resistant. Complete or vast resistance was observed for 5-fluorocytosine, caspofungin, and micafungin. Intraspecific variability of in vitro susceptibility was found in all genera tested but was especially high in Mucor and Rhizopus for azoles and terbinafine. Accurate molecular identification of etiologic agents is compulsory to predict therapy outcome. For species of critical genera such as Mucor and Rhizopus, exhibiting high intraspecific variation, susceptibility testing before the onset of therapy is recommended.Keywords
This publication has 42 references indexed in Scilit:
- Molecular Phylogeny and Proposal of Two New Species of the Emerging Pathogenic FungusSaksenaeaJournal of Clinical Microbiology, 2010
- Apophysomyces elegans : Epidemiology, Amplified Fragment Length Polymorphism Typing, and In Vitro Antifungal Susceptibility PatternJournal of Clinical Microbiology, 2010
- Antifungal Susceptibility Profile of Human-Pathogenic Species of LichtheimiaAntimicrobial Agents and Chemotherapy, 2010
- Spectrum of Zygomycete Species Identified in Clinically Significant Specimens in the United StatesJournal of Clinical Microbiology, 2009
- Activity of Posaconazole and Other Antifungal Agents against Mucorales Strains Identified by Sequencing of Internal Transcribed SpacersAntimicrobial Agents and Chemotherapy, 2009
- A Rapid Bootstrap Algorithm for the RAxML Web ServersSystematic Biology, 2008
- Real-Time PCR Method for Detection of ZygomycetesJournal of Clinical Microbiology, 2008
- In Vitro Susceptibilities of 217 Clinical Isolates of Zygomycetes to Conventional and New Antifungal AgentsAntimicrobial Agents and Chemotherapy, 2007
- In Vitro Activities of Amphotericin B, Caspofungin, Itraconazole, Posaconazole, and Voriconazole against 45 Clinical Isolates of Zygomycetes: Comparison of CLSI M38-A, Sensititre YeastOne, and the EtestAntimicrobial Agents and Chemotherapy, 2007
- In Vitro Activities of Posaconazole, Fluconazole, Itraconazole, Voriconazole, and Amphotericin B against a Large Collection of Clinically Important Molds and YeastsAntimicrobial Agents and Chemotherapy, 2006