title: A flow cytometry method for testing the susceptibility of Cryptococcus spp. to amphotericin B.
abstract: BACKGROUND
  Human fungal infections have increased at an alarming rate in recent years, particularly in immunocompromised individuals. Cryptococcosis is the second most prevalent systemic fungal infection worldwide, and the most prevalent systemic infection in immunocompromised individuals, representing more than 70% of cases. The incidence of cryptococcosis is high in people with HIV/acquired immunodeficiency syndrome (AIDS), with recent estimates indicating that there are one million cases of cryptococcal meningitis globally per year in AIDS patients.
  
  
  OBJECTIVE
  The aim of this research was to develop a rapid flow cytometric antifungal susceptibility test and to compare the results with the standard methods.
  
  
  METHODS
  A reference strain and clinical isolates of Cryptococcus neoformans and Cryptococcus gattii were tested for susceptibility to amphotericin B by flow cytometry using propidium iodide as indicator of viability. Flow cytometry (FC) results were compared with the minimum inhibitory concentration (MIC) values determined by microdilution.
  
  
  RESULTS
  The antifungal activity of amphotericin B ranged from MICs of 0.06 to 2μg/ml for the 11 isolates studied. The same results were found by FC.
  
  
  CONCLUSIONS
  The FC method allows same-day results, assisting in the selection of appropriate antifungal therapies. These results demonstrate an excellent correlation between FC and the classic methods of testing for susceptibility to antifungal agents. This rapid diagnosis method makes it possible to quickly administer effective therapeutic interventions, often saving lives.
authors: Department of Clinical Analysis, Laboratory of Clinical Mycology, Faculty of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil.
authors: Tatiane
authors: T
authors: Benaducci
authors: Department of Clinical Analysis, Laboratory of Clinical Mycology, Faculty of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil.
authors: Marcelo Teruyuki
authors: MT
authors: Matsumoto
authors: Department of Clinical Analysis, Laboratory of Clinical Mycology, Faculty of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil.
authors: Janaina Cássia Orlandi
authors: JC
authors: Sardi
authors: Department of Clinical Analysis, Laboratory of Clinical Mycology, Faculty of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil.
authors: Ana Marisa
authors: AM
authors: Fusco-Almeida
authors: Department of Clinical Analysis, Laboratory of Clinical Mycology, Faculty of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil. Electronic address: giannini@fcfar.unesp.br.
authors: Maria José Soares
authors: MJ
authors: Mendes-Giannini
mesh_terms: D000666:Amphotericin B / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology*; D056285:Cryptococcus gattii / Q000187:drug effects*; D003455:Cryptococcus neoformans / Q000187:drug effects*; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D008826:Microbial Sensitivity Tests; D013997:Time Factors
chemical_list: D000935:Antifungal Agents; D000666:Amphotericin B
keywords: Amphotericin B; Anfotericina B; Citometría de flujo; Concentración mínima inhibitoria; Cryptococcus gattii; Cryptococcus neoformans; Flow cytometry; Minimum inhibitory concentration