, Volume 145, Issue 3, pp 131–135 | Cite as

Comparative Study of Agar Diffusion Test and the NCCLS Macrobroth Method for In Vitro Susceptibility Testing of Candida spp.

  • Luciana Maria Faiad Soni
  • Marcelo Nascimento Burattini
  • Antonio Carlos Campos Pignatari
  • Olga Fischman Gompertz
  • Arnaldo Lopes Colombo


We performed a prospective double-blind study to evaluate the correlation between inhibition zones obtained by a disk-diffusion test, using Neo-sensitabs of fluconazole (Rosco Diagnostica), and the MICs generated by the NCCLS macrobroth dilution assay. Eighty clinical isolates, representing 5 of the clinically relevant species of Candida, were tested simultaneously by both methods. A clear inverse correlation was found between the results obtained by both tests (r = −0.69). In addition, there was high degree of agreement between methods in the identification of susceptible isolates. However, the resistance definition by disk-diffusion test had a positive predictive value of only 17%. Our data support the hypothesis that Rosco Fluconazole Neo-sensitabs have potential as a screening test for the identification of Candida isolates susceptible to fluconazole. Resistant isolates should be further investigated by standardized broth procedures.

Candida resistance susceptibility testing 


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Copyright information

© Kluwer Academic Publishers 1999

Authors and Affiliations

  • Luciana Maria Faiad Soni
    • 1
  • Marcelo Nascimento Burattini
    • 1
  • Antonio Carlos Campos Pignatari
    • 1
  • Olga Fischman Gompertz
    • 2
  • Arnaldo Lopes Colombo
    • 1
  1. 1.Division of Infectious DiseasesEscola Paulista de Medicina – UNIFESPSão PauloBrazil
  2. 2.Division of Cellular BiologyEscola Paulista de Medicina – UNIFESPSão PauloBrazil

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