Open AccessMolecular Studies Reveal Frequent Misidentification of Aspergillus fumigatus by Morphotyping
Author(s) -
S. Arunmozhi Balajee,
David C. Nickle,
János Varga,
Kieren A. Marr
Publication year - 2006
Publication title -
eukaryotic cell
Language(s) - English
Resource type - Journals
eISSN - 1535-9778
pISSN - 1535-9786
DOI - 10.1128/ec.00162-06
Subject(s) - aspergillus fumigatus , biology , voriconazole , aspergillosis , caspofungin , microbiology and biotechnology , aspergillus , amphotericin b , antifungal , immunology
Aspergillus fumigatus has been understood to be the most common cause of invasive aspergillosis (IA) in all epidemiological surveys. However, recent studies have uncovered a large degree of genetic heterogeneity between isolates morphologically identified asA. fumigatus , leading to the description of a new species,Aspergillus lentulus . Here, we examined the genetic diversity of clinical isolates identified asA. fumigatus using restriction enzyme polymorphism analysis and sequence-based identification. Analysis of 50 clinical isolates from geographically diverse locations recorded the presence of at least three distinct species:A. lentulus ,Aspergillus udagawae , andA. fumigatus . In vitro,A. lentulus isolates demonstrated decreased susceptibility to antifungal drugs currently used for IA, including amphotericin B, voriconazole, and caspofungin;A. udagawae isolates demonstrated decreased in vitro susceptibility to amphotericin B. Results of the present study demonstrate that current phenotypic methods to identify fungi do not differentiate between genetically distinct species in theA. fumigatus group. Differential antifungal susceptibilities of these species may account for some of the reported poor outcomes of therapy in clinical studies.