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Azole preexposure affects the Aspergillus fumigatus population in patients.

ABSTRACT: The relationship between the azole preexposure of 86 patients and the genotype, azole susceptibility, and cyp51A polymorphisms of 110 corresponding Aspergillus fumigatus isolates was explored. Isolates carrying serial polymorphisms (F46Y and M172V with or without N248T with or without D255E with or without E427K) had higher itraconazole MICs (P = 0.04), although <2 ?g/ml using the EUCAST methodology, were associated with two genetic clusters (P < 0.001) and with voriconazole preexposure of patients (P = 0.016). Voriconazole preexposure influences the distribution of A. fumigatus isolates with selection of isolates carrying cyp51A polymorphisms and higher itraconazole MICs.

SUBMITTER: Alanio A

PROVIDER: S-EPMC3421863 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Azole preexposure affects the Aspergillus fumigatus population in patients.

Alanio Alexandre A Cabaret Odile O Sitterlé Emilie E Costa Jean-Marc JM Brisse Sylvain S Cordonnier Catherine C Bretagne Stéphane S

Antimicrobial agents and chemotherapy 20120618 9

The relationship between the azole preexposure of 86 patients and the genotype, azole susceptibility, and cyp51A polymorphisms of 110 corresponding Aspergillus fumigatus isolates was explored. Isolates carrying serial polymorphisms (F46Y and M172V with or without N248T with or without D255E with or without E427K) had higher itraconazole MICs (P = 0.04), although <2 μg/ml using the EUCAST methodology, were associated with two genetic clusters (P < 0.001) and with voriconazole preexposure of patie ...[more]

PMID: 22710122

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