Population-Based Survey of Filamentous Fungi and Antifungal Resistance in Spain (FILPOP Study)

Abstract

ABSTRACTA population-based survey was conducted to investigate the epidemiology of and antifungal resistance in Spanish clinical strains of filamentous fungi isolated from deep tissue samples, blood cultures, and respiratory samples. The study was conducted in two different periods (October 2010 and May 2011) to analyze seasonal variations. A total of 325 strains were isolated in 29 different hospitals. The average prevalence was 0.0016/1,000 inhabitants. Strains were identified by sequencing of DNA targets and susceptibility testing by the European Committee for Antimicrobial Susceptibility Testing reference procedure. The most frequently isolated genus wasAspergillus, accounting for 86.3% of the isolates, followed byScedosporiumat 4.7%; the order Mucorales at 2.5%;Penicilliumat 2.2%, andFusariumat 1.2%. The most frequent species wasAspergillus fumigatus(48.5%), followed byA. flavus(8.4%),A. terreus(8.1%),A. tubingensis(6.8%), andA. niger(6.5%). Cryptic/siblingAspergillusspecies accounted for 12% of the cases. Resistance to amphotericin B was found in 10.8% of the isolates tested, while extended-spectrum triazole resistance ranged from 10 to 12.7%, depending on the azole tested. Antifungal resistance was more common among emerging species such as those ofScedosporiumand Mucorales and also among cryptic species ofAspergillus, with 40% of these isolates showing resistance to all of the antifungal compounds tested. CrypticAspergillusspecies seem to be underestimated, and their correct classification could be clinically relevant. The performance of antifungal susceptibility testing of the strains implicated in deep infections and multicentric studies is recommended to evaluate the incidence of these cryptic species in other geographic areas.