title: In vitro susceptibilities of Candida spp. to caspofungin: four years of global surveillance.
abstract: Caspofungin is being used increasingly as therapy for invasive candidiasis. Prospective sentinel surveillance for emergence of in vitro resistance to caspofungin among invasive Candida spp. isolates is indicated. We determined the in vitro activity of caspofungin against 8,197 invasive (bloodstream or sterile-site) unique patient isolates of Candida collected from 91 medical centers worldwide from 1 January 2001 to 31 December 2004. We performed antifungal susceptibility testing according to the Clinical and Laboratory Standards Institute (CLSI, formerly NCCLS) M27-A2 method and used a 24-h prominent inhibition endpoint for determination of the MIC. Of 8,197 invasive Candida spp. isolates, species distribution was as follows: 54% Candida albicans, 14% C. glabrata, 14% C. parapsilosis, 11% C. tropicalis, 3% C. krusei, and 4% other Candida spp. Overall, caspofungin was very active against Candida (MIC50/MIC90, 0.03/0.25 microg/ml; 98.2% were inhibited at a MIC of < or = 0.5 microg/ml and 99.7% were inhibited at a MIC of < or = 1 microg/ml). Results by species (expressed as MIC50/MIC90 and the percentage inhibited at < or = 1 microg/ml) were as follows: C. albicans, 0.03/0.06, 99.9; C. glabrata, 0.03/0.06, 99.9; C. parapsilosis, 0.5/0.5, 99.0; C. tropicalis, 0.03/0.06, 99.7; C. krusei, 0.12/0.5, 99.0; and C. guilliermondii, 0.5/1, 94.4. Of the 25 isolates with caspofungin MICs of >1 microg/ml, 12 isolates were C. parapsilosis, 6 isolates were C. guilliermondii, 2 isolates were C. rugosa, and 1 isolate each was C. albicans, C. glabrata, C. krusei, C. lusitaniae, and C. tropicalis. There was no significant change in caspofungin activity over the 4-year study period. Likewise, there was no difference in activity by geographic region. Caspofungin has excellent in vitro activity against invasive clinical isolates of Candida from centers worldwide. Our prospective sentinel surveillance reveals no evidence of emerging caspofungin resistance among invasive clinical isolates of Candida.
authors.affiliation: Departments of Pathology, Epidemiology, Roy J. and Lucille A. Carver College of Medicine and College of Public Health, University of Iowa, Iowa City, Iowa 52242, USA. michael-pfaller@uiowa.edu
authors.forename: M A
authors.initials: MA
authors.lastname: Pfaller
authors.forename: L
authors.initials: L
authors.lastname: Boyken
authors.forename: R J
authors.initials: RJ
authors.lastname: Hollis
authors.forename: S A
authors.initials: SA
authors.lastname: Messer
authors.forename: S
authors.initials: S
authors.lastname: Tendolkar
authors.forename: D J
authors.initials: DJ
authors.lastname: Diekema
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D002175:Candida / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification; D002177:Candidiasis / Q000188:drug therapy / Q000382:microbiology; D000077336:Caspofungin; D025141:Drug Resistance, Fungal; D054714:Echinocandins; D006801:Humans; D066298:In Vitro Techniques; D055666:Lipopeptides; D008826:Microbial Sensitivity Tests; D010456:Peptides, Cyclic / Q000494:pharmacology*; D013045:Species Specificity; D013997:Time Factors
chemical_list: D000935:Antifungal Agents; D054714:Echinocandins; D055666:Lipopeptides; D010456:Peptides, Cyclic; D000077336:Caspofungin