title: Variations in fluconazole susceptibility and DNA subtyping of multiple Candida albicans colonies from patients with AIDS and oral candidiasis suffering one or more episodes of infection.
abstract: Five Candida albicans colonies from each infection in AIDS patients receiving fluconazole therapy for oropharyngeal candidiasis over a 2-year period were evaluated by antifungal susceptibility testing and DNA subtyping, and the results were correlated with clinical response to determine the occurrence of clinically significant selection of more-resistant C. albicans over multiple infections. A total of 534 C. albicans isolates were obtained from 38 patients who exhibited 84 episodes of infection. Antifungal susceptibility testing revealed that the MICs for 93% of the isolates were < or = 8.0 microg/ml and the MICs for 7% of the isolates were > or = 64 microg/ml. DNA subtyping revealed 70 different subtypes, with 78% of patients with one infection exhibiting one DNA subtype and 80% of patients with more than one infection exhibiting multiple DNA subtypes. Also, patients who had multiple infections had lower CD4 counts than those with single infections. Differences between the single-infection group and the multiple-infection group regarding the number of DNA subtypes and CD4 counts were both statistically significant. Of the 74 evaluable infections all were successfully treated with regular-dose (100-mg/day) fluconazole, except for three patients who ultimately responded to higher-dose fluconazole. Only one patient may have shown clinically significant selection of a more-resistant C. albicans strain over multiple courses of treatment. Interestingly, MICs reached only 8.0 microg/ml, even though doses of 400 mg of fluconazole were necessary for clinical cure.
authors.affiliation: Department of General Dentistry, University of Texas Health Science Center, San Antonio 78284, USA.
authors.forename: S W
authors.initials: SW
authors.lastname: Redding
authors.forename: M A
authors.initials: MA
authors.lastname: Pfaller
authors.forename: S A
authors.initials: SA
authors.lastname: Messer
authors.forename: J A
authors.initials: JA
authors.lastname: Smith
authors.forename: J
authors.initials: J
authors.lastname: Prows
authors.forename: L L
authors.initials: LL
authors.lastname: Bradley
authors.forename: A W
authors.initials: AW
authors.lastname: Fothergill
authors.forename: M G
authors.initials: MG
authors.lastname: Rinaldi
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000188:drug therapy / Q000382:microbiology*; D000935:Antifungal Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002176:Candida albicans / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D002180:Candidiasis, Oral / Q000188:drug therapy / Q000382:microbiology*; D004271:DNA, Fungal / Q000032:analysis / Q000235:genetics*; D015725:Fluconazole / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D008826:Microbial Sensitivity Tests
chemical_list: D000935:Antifungal Agents; D004271:DNA, Fungal; D015725:Fluconazole