Open AccessMolecular typing and antifungal susceptibility of clinical sequential isolates of Cryptococcus neoformans from Sao Paulo State, Brazil
Author(s) -
Almeida Ana Marisa Fusco,
Matsumoto Marcelo Teruyuki,
Baeza Lilian Cristiane,
De Oliveira e Silva Rosana Bellan,
Kleiner Aline Aparecida Pizzirani,
Melhem Márcia de Souza Carvalho,
Mendes Giannini Maria José Soares
Publication year - 2007
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/j.1567-1364.2006.00128.x
Subject(s) - cryptococcus neoformans , biology , rapd , amphotericin b , fluconazole , itraconazole , microbiology and biotechnology , cryptococcus , flucytosine , cryptococcosis , cryptococcus gattii , typing , antifungal drug , antifungal , genetic diversity , population , medicine , environmental health
The antifungal susceptibility profiles and the genetic variability of 83 sequential clinical isolates of Cryptococcus neoformans , including four Cryptococcus gattii isolates, obtained from 38 Sao Paulo AIDS patients with cryptococcal meningitis were assessed by electrophoretic karyotyping and random amplified polymorphic DNA (RAPD) analysis. The majority of the Cryptococcus neoformans isolates were highly susceptible to amphotericin B and fluconazole. Twenty percent of the minimum inhibitory concentration values for amphotericin B varied from 0.5 to 1 μg mL −1 . For fluconazole, 22% occurred in the range 8–16 μg mL −1 . Sequential isolates from nine patients showed a trend towards lower susceptibility to fluconazole, flucytosine, itraconazole and amphotericin B. The results of molecular typing by electrophoretic karyotyping and RAPD analysis showed the presence of 22 electrophoretic karyotypes (EK) and 15 RAPD profiles that were highly correlated. Our results provided evidence for the occurrence of genetic changes in some strains associated with microevolution during the course of infection. We also observed both microevolution and simultaneous coinfection with two distinct Cryptococcus neoformans strains in one patient. In some patients, we found changed EK‐ and RAPD patterns in association with increased MIC values.