A prospective survey of Aspergillus spp. in respiratory tract samples: Species identification and susceptibility patterns

Med Mycol. 2019 Jun 1;57(4):412-420. doi: 10.1093/mmy/myy080.

Abstract

We analyzed the species distribution and susceptibility patterns of 433 strains of Aspergillus spp. isolated from respiratory samples of 419 in-patients included in multicenter prospective study (FUNGAE-IFI) between July 2014 and October 2015. Identification was carried out by conventional methods at each participating center and by molecular sequencing of a portion of the β-tubulin gene at one of the centers. In vitro susceptibility was evaluated by broth microdilution methods and using the E-test (for cryptic species). Species identified included 249 A. fumigatus sensu stricto, 60 A. terreus sensu stricto, 47 A. flavus sensu stricto, 44 A. tubingensis, 18 A. niger sensu stricto , five A. nidulans sensu stricto, three A. tamarii, two A. calidoustus, two A. carneus, one A. acuelatus, one A. carbonarius, and one A. sydowii. Cryptic species were found in 12.5% of isolates (n = 54). The frequency of non-wild-type isolates for amphotericin B was 3.4% (n = 15) of the isolates tested and for azoles 3% (n = 10). None of the Aspergillus spp. were non-wild type to echinocandins. Of the 54 cryptic species only two strains were non-wild-type strains by microdilution method (3.7%) (two A. tubingensis, one to amphotericin B and another one to voriconazole) and by E-test method five strains of A. tubingensis showed high minimal inhibitory concentration (MIC) to amphotericin B (11.4%) and five to azoles (12.1%), one A. calidoustus strain showed high MICs for three azoles (50%), A. carneus to itraconazole (100%) and A. sydowii to amphotericin B and itraconazole (100%). These results provide relevant information on susceptibility patterns, frequency, and epidemiology of species involved in respiratory tract samples and of the incidence of recently described cryptic species.

Keywords: Aspergillus spp; cryptic species; hospitalized patients; respiratory tract samples.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antifungal Agents / pharmacology*
  • Aspergillosis / epidemiology*
  • Aspergillosis / microbiology*
  • Aspergillus / classification*
  • Aspergillus / drug effects
  • Aspergillus / isolation & purification*
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Incidence
  • Infant
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Prospective Studies
  • Respiratory Tract Infections / epidemiology*
  • Respiratory Tract Infections / microbiology*
  • Sequence Analysis, DNA
  • Surveys and Questionnaires
  • Tubulin / genetics
  • Young Adult

Substances

  • Antifungal Agents
  • Tubulin