Effect of 50% human serum on the killing activity of micafungin against eight Candida species using time-kill methodology.
Micafungin activity was determined against 24 wild-type clinical isolates and 5 American Type Culture Collection strains belonging to 8 Candida species in RPMI-1640 with and without 50% serum using broth microdilution and time-kill methodology. MIC values increased from 4- to 128-folds in 50% serum for all Candida species. Micafungin was not fungicidal against C. albicans, C. tropicalis, and against 2 of 3 C. metapsilosis at ≥0.25, 1, and 1 μg/mL, respectively, after 48 h with 50% serum, showing good fungistatic activity. Fungicidal activity at ≥2, 4, and 32 μg/mL was noticed against C. glabrata, C. inconspicua, and C. krusei isolates, respectively. Micafungin at 8-32 μg/mL showed fungistatic activity against C. parapsilosis and C. orthopsilosis. Serum decreased the in vitro activity of micafungin. With serum binding of echinocandins taken into account, safely fungistatic or fungicidal concentrations seem to require elevated doses against some Candida species, including C. parapsilosis, C. orthopsilosis, and C. krusei.
Department of Medical Microbiology, Medical and Health Science Center, University of Debrecen, 4032 Debrecen, Hungary.
Richárd
R
Földi
Judit
J
Szilágyi
Gábor
G
Kardos
Réka
R
Berényi
Renátó
R
Kovács
László
L
Majoros
D000935:Antifungal Agents / Q000494:pharmacology*; D002175:Candida / Q000187:drug effects*; D003470:Culture Media / Q000737:chemistry*; D054714:Echinocandins / Q000494:pharmacology*; D006801:Humans; D055666:Lipopeptides / Q000494:pharmacology*; D000077551:Micafungin; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects*; D044967:Serum / Q000378:metabolism*; D013997:Time Factors
D000935:Antifungal Agents; D003470:Culture Media; D054714:Echinocandins; D055666:Lipopeptides; D000077551:Micafungin