Azole resistance in canine and feline isolates of Aspergillus fumigatus

Comp Immunol Microbiol Infect Dis. 2015 Oct:42:37-41. doi: 10.1016/j.cimid.2015.08.002. Epub 2015 Aug 28.

Abstract

Azole resistance is an emerging cause of treatment failure in humans with aspergillosis. The aim of this study was to determine if azole resistance is emerging in Aspergillus fumigatus isolates from canine and feline sino-nasal aspergillosis cases. Susceptibilities of isolates collected between 1988 and 2014 from 46 dogs and 4 cats to itraconazole, posaconazole, voriconazole, fluconazole and ketoconazole were assessed using Sensititre YeastOne microdilution trays; and to enilconazole and clotrimazole, following the CLSI M38-A2 standard. For the majority of isolates MICs were high for ketoconazole, low for enilconazole and clotrimazole, and less than established epidemiological cut-off values for itraconazole, posaconazole and voriconazole. One canine isolate from 1992 had multiazole resistance and on Cyp51A gene sequencing a mutation associated with azole resistance (F46Y) was detected. There is no evidence of emerging azole resistance among A. fumigatus isolates from dogs and cats and topical azole therapy should be effective against most isolates.

Keywords: Aspergillosis; Aspergillus fumigatus; Azole resistance; Clotrimazole; Enilconazole.

MeSH terms

  • Animals
  • Antifungal Agents / pharmacology*
  • Aspergillosis / microbiology
  • Aspergillosis / veterinary*
  • Aspergillus fumigatus / drug effects*
  • Aspergillus fumigatus / genetics
  • Aspergillus fumigatus / isolation & purification*
  • Cat Diseases / microbiology*
  • Cats
  • Cytochrome P-450 Enzyme System / genetics
  • Dog Diseases / microbiology*
  • Dogs
  • Drug Resistance, Fungal / genetics
  • Fungal Proteins / genetics
  • Itraconazole / pharmacology
  • Microbial Sensitivity Tests
  • Mutation
  • Triazoles / pharmacology
  • Voriconazole / pharmacology

Substances

  • Antifungal Agents
  • Fungal Proteins
  • Triazoles
  • Itraconazole
  • posaconazole
  • Cytochrome P-450 Enzyme System
  • cytochrome P-450 CYP51A, Aspergillus
  • Voriconazole