title: Molecular identification, genotyping, and antifungal susceptibility testing of clinically relevant Trichosporon species from Argentina.
abstract: Trichosporon species are emerging causative agents of mycoses; most are documented in immunocompromised patients. Species identification is important for epidemiological purposes in order to better define species clinical associations and to improve antifungal treatment. Here, we studied a collection of 41 Trichosporon strains recovered from hospitalized patients in Argentina. All strains were identified by sequencing the D1/D2 domain of 26S, internal transcribed spacer (ITS) regions, and intergenic spacer 1 (IGS1) region. In addition, we determined the IGS1 region genotypes of the suspected T. asahii strains. Antifungal susceptibility of all strains was investigated. Thirty-eight of the 41 strains in this study were identified as follows: 29 T. asahii, 3 T. inkin, 3 T. montevideense, 2 T. faecale, and 1 T. dermatis. The identity of the three remaining strains could not be confirmed. Strain DMic 114126 (Culture collection of the Mycology Department (DMic), National Institute of Infectious Diseases "Dr. Carlos G. Malbrán".) may represent a T. asahii subspecies or a new Trichosporon species, strain DMic 94750 was identified as T. cf. guehoae and strain DMic 114132 as T. cf. akiyoshidainum. The distribution of T. asahii genotypes was as follows: 12 genotype 3, 9 genotype 1, 4 genotype 4, 2 genotype 5, and 2 genotype 7. Amphotericin B minimal inhibitory concentrations (MICs) were ≤1 mg/l for 78% (32/41) of the strains. Fluconazole MICs were ≥2 mg/l for 90% of the strains. However, itraconazole, voriconazole, ketoconazole, and posaconazole MICs were ≤1 mg/l for 100% of the strains. Terbinafine MICs were ≤1 mg/l for 98% 40/41 of the strains.
authors.affiliation: Departamento Micología, Instituto Nacional de Enfermedades Infecciosas "Dr. Carlos G. Malbrán," Ciudad Autónoma de Buenos Aires, Argentina.
authors.forename: Constanza Giselle
authors.initials: CG
authors.lastname: Taverna
authors.forename: Susana
authors.initials: S
authors.lastname: Córdoba
authors.forename: Omar Alejandro
authors.initials: OA
authors.lastname: Murisengo
authors.forename: Walter
authors.initials: W
authors.lastname: Vivot
authors.forename: Graciela
authors.initials: G
authors.lastname: Davel
authors.forename: María Eugenia
authors.initials: ME
authors.lastname: Bosco-Borgeat
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D001118:Argentina; D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D058889:Molecular Typing; D016533:Mycological Typing Techniques; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics; D017422:Sequence Analysis, DNA; D014250:Trichosporon / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D060586:Trichosporonosis / Q000382:microbiology*
chemical_list: D000935:Antifungal Agents; D004271:DNA, Fungal; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012335:RNA, Ribosomal; C065096:RNA, ribosomal, 26S
keywords: IGS1; Trichosporon; genotyping; identification; sequencing