Molecular heterogeneity of fluconazole-resistant and -susceptible oral Candida albicans isolates within a single geographic locale

APMIS. 2002 Apr;110(4):315-24. doi: 10.1034/j.1600-0463.2002.100406.x.

Abstract

The emergence of drug-resistant Candida albicans in immunocompromised patients is common. A disconcerting aspect of this phenomenon is the rapid emergence of C. albicans strains that are resistant to a widely used azole drug, fluconazole (FLZ). To understand the origin of FLZ-resistant yeast isolates, we investigated molecular profiles of 20 geographically related oral C. albicans isolates using three genotyping methods: randomly amplified polymorphic DNA-PCR, with six different primers (OBU1, OBU2, OBU3 RSD6, RSD11 and RSD12); electrophoretic karyotyping by pulsed-field gel electrophoresis; and HinfI restriction fragment analysis. Of the 20 isolates studied, 10 were FLZ- resistant and originated from patients with oral candidosis with a history of FLZ therapy, and the remainder were FLZ susceptible from individuals with oral candidosis, but without a history of FLZ therapy. A composite genotype was generated for each strain by combining molecular types derived from the three independent molecular methods. The composite profiles indicated genetic diversity amongst both the FLZ-resistant as well as -sensitive isolates, and no specific features emerged distinguishing the drug-resistant and -sensitive groups. These observations cast doubt on the theory of a clonal origin of FLZ-resistant C. albicans isolates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antifungal Agents / pharmacology*
  • Candida albicans / drug effects*
  • Candida albicans / genetics*
  • Candida albicans / isolation & purification
  • Drug Resistance, Fungal / genetics*
  • Fluconazole / pharmacology*
  • Genetic Variation
  • Genotype
  • Humans
  • Mouth Mucosa / microbiology*
  • Polymerase Chain Reaction

Substances

  • Antifungal Agents
  • Fluconazole